o THE ROTIFEEA; OR WHEEL-ANIMALCULES C BY ,? T HUDSON, LL.D Cantab ASSISTED BT P IN H GDSSE, F.E.S TWO VOLUMES VOLUxME II WITH ILLUSTRATIONS LONDON: LONGMANS, GREEN, AND ^' 1886 All rights reserved CO, : MCZ LIBRARY HARVARD UNIVERSITY CAMBRIDGE MA USA ) Those viewless beings, ^Tiose mansiou the smallest particle is Of the impassive atmosphere, Enjoy and live like man And the minutest throb That through The their slightest, Is fixed, frame diffuses famtest motion, and indispensable As the majestic laws That rule yon rolling orbs Shelley Qui em-iosus postulat totum suae Patere menti, ferre qui non sufficit Mediocritatis conscleutiam suae Judex iniquus, estimator Suique naturieque ; est mains nam rerum parens, Libanda tantum quae venit mortalibus, Nos scu'e pauca, multa mirari jubet Grottos — CONTENTS T HE 1: CON CllAPTEU I'LohiA (iL-LoracATA PLoniA (LORICATA) M V LX finned) CIIAPTEPi V roll CHAPTER KCIRTOrODA VOL D i X .')7 XL '.J'J ADDENDA ATPENDLK : THE VASCULVr SYSTEM THE SSTIGEUOUS SENSE -ORG.iXS EiBLIOaRAPHY OF THE KOTIFERA INDEX ]:','.) 110 /^' CHAPTER IX PLOIMA I It L-LORIC ATA— continued.) — — ; : ; Les actions des betes sont peut-etre un des plus profonds abimes sn quoi notre raison se puisse exercer; et je suis siirpris que si peu de gens s'en apeivoivent Bayle Their good They is good entire, unmixed, unmarred find a paradise in every field On boughs forbidden where no ciu'ses hang Their ill, no more than strikes the sense, unstretched By previous dread, or murmiu' in the rear When the worst comes, it comes unfeared one stroke Begins and ends their woe Young ; CHAPTEK Family VIII TEIAETHRAD.E 'Boiy fiirnisheclwith skipping appendages marginal ; IX corona transverse ; ; ciliary wreath single, foot absent The four genera which form this family resemble each other in one striking particular Each bears spines, or moveable appendages, by means of which the creature can leap These spmes have no connection with the body-cavity, though they which, in sharply withdrawing the head, throw the spines forward In one genus, I'tcroessa, which is known only by in another, its lorica, the spines are very numerous, and are of two distinct patterns Polyarthra, they are clusters of blades borne upon the shoulders in the remaming two, Triarthra and Pcdctes, there is only one simple spine on each shoulder, but Triarthra carries also a similar spine on the posterior ventral surface All the genera are more or less loricated In Pedetes the skin bears hard knobs for the attachment of the spines, while Triarthra has it stiffened chiefly round the edge below the neck Polyarthra is semi-loricated the dorsal surface is very tough and there is a still harder shield on each side between the dorsal and ventral surfaces The ventral surface, however, is soft and membranous In all, the longitudinal muscles are highly developed, and through the water are moved indirectly by the usual longitudinal muscles ; ; ; ; coarsely striated The genera differ Melicerta ringens ; in their tropin in Pedetes the trophi Triarthra has the malleo-ramate trophi of have not been clearly defined while Poly; either, has a mastax and trophi closely resembling those of Synchata Polyarthra, moreover, is still further separated from Pedetes and Triarthra by having one occipital eye, instead of two frontal arthra, widely unlike Genus POLYARTHEA, Ehrenberg GEN CH Spines in clusters on the shoulders very large and pear-shaped It is ; eye single, occipital mastax ; trophi forcipate not easy to decide in which family the genus Polyarthra should be placed ; Its mastax and trophi are almost exactly those of Synchceta its corona bears styligerous prominences similar to those of S pectinata its ciliary wreath is marginal and single, though not broken up into curves and, like Synchata, it possesses but one occipital eye On the other hand its skipping spines naturally place it with Triarthra and Pedetes, which genera it further resembles by its lack of foot, by its habit of carrying its eggs, and by the partial stiffening of its skin into an imperfect lorica ; ; ; P PLATYPTEBA, Ehrenbcrg (PL XIII Polyarthra platyptera' fig 5.) Ehrenberg, Die Jk/im 1838, p 441, Taf liv fig Leydig, Ueb d Ban d Raderth 1854, p 42, Taf i Gosse, Fhil Trans 1856, p 435, pi xvii figs 1857, p 320, pi XV figs is 10 27-29 Plate, Jenaisch Zeits.f Natur 1885, p 16, Taf Ehrenberg's P Irigla fig 44-49 possibly P platyptera with the blades seen edgewise i fif THE ROTIFEEA SP CH When Spines twelve broad blades icith serrate edges gliding along under the action of wreath Pohjarthra seems to have tnmcated both in front and rear, carries four clusters of serrated blades fastened to the shoulders and these trail behind so as nearly' to meet in a point, at some distance from the animal's body Every now and then the blades are jerked vigorously forward, and the creature is tossed out of its path, several times its own length The trunk is partially loricated There is a kind of chitinous shield running down each side of the body, pointed at its hinder end, and bent at the sides so as to encroach a little on the tough dorsal and membranous ventral a triangular outline ; for the ciliary its body, though itself ; surfaces The edge of the dorsal lorica (if it may be so termed) is plainly visible running across from one cluster of blades to the other A pair of powerful striated muscles, forming a letter V, is fastened to the lower pointed end of the shield, and to the inner surface of the soft tissues, to which, at the upper end on each side, six of the blades are attached The contraction of these V-shaped muscles drags the soft tissues sharply down over the hard edge of the shield, and makes the blades fly out with great swiftgeneral outlme (fig 5d), ha\dng ness The blades are curiously like a bird's feather a midrib (fig 5c) and being distmctly serrated on both edges The corona is slightly convex and bears, towards the dorsal surface, two prominences like those of Synchceta There are also two long styles facing these, fectinata, each carrying a brush of styles and springing fi-om the corona towards the ventral surface Mr Gosse has, moreover, noticed, besides these tactile organs, a small occipital pimple armed with bristles The m very large mastax points obliquely downward Both it, and its The contractile vesicle can be easily to the ventral surface tropin, closely resemble those of Synchceta pectinata seen, hut neither lateral canal nor vibratile tags have been recorded internal structure requires notice.' its The animal Nothing else in carries the great female egg singly, and transversely, between the points of the two side shields but the small male eggs in more at a time (fig 5b] The male was discovered by Mr Gosse in 1850, and described and figured by him in the " Phil Trans." for 1856 [Its length is only -^\-^ inch The head is very large (fig 5/;) and the body tapers quickly to the posterior part, but both extremities are truncate The front bears two warts between which the rotatory cilia are placed, but the cilia are longer (perhaps setiE) on the warts ; clusters of half-a-dozen or The hinder part is bifid, the smaller division bemg the caudal extremity or toe-less foot, and the latter a protrusile truncate penis ciliated at the tip No internal organization was discoverable P.H.G.] Dr Plate's figure [loc cit.) shows the sperm-sac Length Female's body, ^jj^ inch Habitat Pools and ponds common — : Genus PTER0ES3A, Gosse [GEN Lorica entire, save for a large oval opening behind ; beset with articulate pinnate styles, and simple setae ; foot wanting CII P suBDA, Gosse, sp nov (PL XIII 8P CH The only known species fig Horny 9.) yellou- ; pinase twenty-four, in six longi- tudinal rows The form of this remarkable species is that of an ancient amphora ; a long oval tapering to an obtuse point, with no foot, forming a constricted neck, in front, and thence ' An Bhizota observation of Mr Gosse's leads ; and that it is him to think that the rectum is turned far forward as in the cajiablc of considerable protrusion, thoiigli ordinarily invisible TRIARTIIRAD.-E expanding to a broad truncate margin Beliind there is a great ovate opening, as if a Doubtslice had been cut off the entire breadth from the middle to the extreme point From the upper less this, in life, is covered with membrane, and its edge is thickened margin rise two short setae, jointed to knobs while from the breast, exactly opposite, there issues another, similarly jointed but of great length, descending far behind the ; extremity of the body But the chief peculiarity of the creature is that four-and-twenty styles, regularly For every one is a arranged, are affixed to the lorica, giving a most unique aspect to it its two pmnules like those of a fern (Polypodium, for instance), in These pinnre are arranged in considerable number, length, and regularity (fig 9c) six longitudinal rows, three on each side, on the ventral aspect, the middle pair of rows consisting of six each, the next pair four, and the outmost two, each The shaft of each is evidently articulated on a knob of chitine, which is itself a tubercle on a somewhat larger round knob, set in a commensurate orifice in the lorica, apparently moving freely in it, a true " ball and socket " joint, worked doubtless by proper muscles within Thus, adding the three simple styles, which are similarly based, we have here a wonderful array of exterior articulate members, which well illustrate the claim of the Eotifeka to a place among the ARTHROPODA The pinnules vary much in their number, their length, and the angle of their expansion The body ends in a blunt point, with no foot, nor other appendage The anterior extremity, beyond the marked neck, is short, somewhat inclined toward the back, truncate, with an orifice as wide as the widest part of the trunk Through this, of course, the head is protruded during life but of this, and of the whole internal organization, I can give no information The specimen which came under my observation was an empty lorica, in good isreservation, as if recently dead, which I was enabled to revolve under the microscope, and so to examine in several aspects The whole lorica was of a dark yellow-brown hue, with a dull translucency like that of a smoky horn lantern but whether this is specific, or only accidental, I feather in appearance ; the shaft, moderately long and stout, being beset, on opposite sides, with regular — ; : cannot tell This most curious form occurred in the sediment of a bottle of water, examined on October 20, 1885, but which had been standing on my table since September 23, when I had received it from Mr Hood with a colony of Scarklium eudactylotum From the condition of the lorica I have little doubt that it had come to me alive but being occupied with the new Scaridium I did not search closely P.H.G.] Length Of lorica, yjj, inch to tips of pinna, ^'3 inch from brow of lorica to tip of ventral seta, ~\ inch Habitat Loch near Dundee (P.H.G.) ; — ; ; Genus TRIARTHRA, Ehrenberg GEN CH Spines siinjlo, two lateral, one ventral; eyes two frontal ; inastax of tnoderate size; trophi malleo-ramato There are three known species of closely ; the main points this genus, and they resemble each other very of difference being the length of the leaping-spines, the distance between the eyes, and the length of the oesophagus The first of these characters is one that cannot be much relied on except in the case of T breviseta for the length of the spines varies very much in the same species Ehrenberg makes a further point of difference, in the presence or absence of any well marked separation between the stomach and intestine, asserting that T longiseta possesses this separation and that T mystacina lacks it This, however, is a character of small value, for the same animal will show at one time an undivided alimentary canal and, at another, one sharply di\ided into intestine and stomach ; ; TIH H0T1FKI;.\ T LONGISETA, Eliivuhrrg (PL XIII Triaithra longiseta „ „ „ „ Body SP CH The In/its 1838, p 447, Tai Iv fig Hudson, Mon Micr Grenacher, Sieb u xxxvii more than twice 6.) Ehrenberg, Die fig J vol i 1869, p 176, pi Kiill Zeits Bd xix 1869, vi p 491, Taf fig oval; huccal oriS.ce jii'omineiit but not beaked, cup-shaped ; spines the length of the body ejes wide apart ; oesophag'us long ; habit of this interesting creature longer axis, and every now and then to is swim slowly forward while turning round by jerking forwards the oval, and bears in its centre one broad, low prommence, with a smaller one on either side of it and just within each of these latter is placed a red eye The buccal orifice is cup-shaped and has its inner surface lined with cilia The buccal funnel slopes backwards and upwards towards its to dart out of its course three long spines which usually trail behind The corona it is ; the dorsal surface to meet the mastax, whose troi^hi are almost identical with those of The cesophagus is long and narrow, and the stomach and intestine Melicerta ringens The gastric glands (fig 6a) are curiously The vascular shaped, and frequently studded with what appear to be oil-globules system is delicately transparent, and difficult to be seen I have traced the lateral canals are usually separated by a deep constriction on each side, for some distance down the trunk, from a plexus of tubes in the neck, and have detected just there a vibratile tag I failed to discover the contractile vesicle, but Dr Grenacher [he cit.) has seen it, in its usual position, close to the cloaca There is a large ovary and the newly laid eggs remain attached to the parent by a thread for some ; time after their exclusion The ephippial eggs (fig 0/) are as curious in shape as the and are protected by a thick layer of yellowish transparent gastric glands, By cells bringing into focus the central inner portion of the head, seen sidewise, a bluish and roughly rhomboidal mass may be observed this is the nervous ganglion, and above it ; are the eyes, and from it threads extend to a setigerous fossa in the neck, as well as to rocket-headed antennse, one on each side (fig %b) partly is (fig a clear, colourless, refractmg sphere imbedded in, a flat (Je) just under the surface Each eye inch in diameter, restmg on, and The longitudinal muscles- are very -g^^jj plate of red pigment not bemg straight transverse lines, but Indeed they appeared to me to alter both in direction and in size as I looked at them, gi'\"ing me the impression that I was looking at illusory strise, produced possibly by looking through separated sheets of striated fibre, There is an unusually powerful muscular collar running round lying over each otlier powerful, and are strongly striated the ; irregular obliquely transverse curves the neck The and tapering spines are side of the corona, just which the and there appendages, broadest at their attached bases, (fig Gd) are like quills that have been by these cut surfaces that they are attached, one on each stiff quill-like at their free ends obliquely cut across, and striiB (fig 6c) it is The bases above the neck ; and one on the ventral foot springs, in those Eotifera that possess one (fig 6rf), be evident that if and finely imbricated towards their tips surface, at the spot The On from spines are notched here looking at fig 6, it will the muscular collar round the neck be suddenly contracted, and the head withdrawn, the spines will be first dragged across the stiff edge of the trunk, below the collar, and then jerked forward by the downward pull of the head How the third spine is moved is not so clear Dr Grenacher suggests that it is dragged forward by the other two, which are often crossed beneath it but adds that It is probable, I think, that this spine is driven forward this is a forced explanation by the sudden jerk downwards on its base, when the longitudinal muscles sharply comFine muscular fibres surround the trunk at regular frcsT the still ventral cuticle ; ; PLATE XXX redalion niii'uiu side view dorsal view view side view (side limbs removed) showing viscera dorsal view, showing muscles fi'ont H H H H H a,dorsammb|l''^'^P'"^^^°'"^ elevators [2, /3, inner lateral limb Repressors P' (4, y, S, ventral ]i^^\l' 8, { The elevators outer lateral limb -'^'•^^P'^^^^O'"^ (C, elevators ^^Vressoxs elevators ventral depressors (5, 5), of the outer meet a similar dorsal pair on the mid-dorsal and mid-ventral siu:f'aceE and the four together encu'cle the bodj' lateral limbs, There a similar encircling set of four is belonging to the dorsal limb, ventral ^-iew, sho'^^ing muscles (1, 1) 9, H ventral longitudinal muscles for retract- ing head showing muscles muscles for retracting head 11, right depressor of dorsal antenna 12, cu-cular muscles of the neck side view, 1/- H 10, dorsal longitudinal 13, right depressor of chin male, dorsal view male, side view 1^ Ih Hesarthra polyptera ptygura dorsal view fficistes Seison Gnibei female, retracted trophi Drilophaga bucephalus (after head, dorsal view, showing hooks male, extended 4a 46 H H side view ; ; view side view ; side Dr Schmarda) I (after ' J side Brachioniis angularis view |f t'' 5° Vejdovsky) ventral view Copeus sijicatus Braehionus Miilleri (after M Ed Claparede) ventral view dorsal view aperture for lateral antenna H Dr Clans) / attached to Lumbriculus I Balatro cahais \ H H H H *l & V\ \, ^o * If *3 "^- ^^- ^-y \ 1^! ^^ l^ ^il ^^^ > -^ ^ S re ^ :^ ^ PC \ i \ M ^' y - -i : THE ROTIFERA; OB WHEEL-ANIMALCULES The nccotiipanying to Titles enable those irho irlsh it to have been prepared bind the Text and Plates in separate volumes IN TWO VOLUMES TEXT LONDON LONGMANS, GREEN, AND 1886 All rights reserved CO, ^2^ : THE ROTIFBEA; OB, WHEEL-ANIMALGULES BY C T HUDSON, LL.D Cantab ASSISTED BY P H GOSSE, F.R.S WITH ILLUSTRATIONS IN TWO VOLUMES TEXT LONDON LONGMANS, GREEN, AND 1886 AH rights reserved CO, — CiEcam mihi in cimctis fidem haberi baud postulo continua indagatione ae studio mea aliijuando Perscnitatoris vel exactissimi, demonstretui' ; et offert, quae intensissima ssepe cura frustra qusesivimus Cast dans les livres Quelques fois a vero aberrasse lire, nonnunquam fortuito — J Baster quand on veut travailler sur mais on ne pent pas y lire, quand on veut II faut des lieux, des circonstances favorables pour faire des observations necessaires THistoire Naturelle des saisous et de la Nature, qu'on doit tantum optans, ut me quamvis suuimam adhibeat, attentionem fugere aliquando quiedam possunt; et casus nobis id confirmentur, aut i, ; la v^rite mais plus souvent il on pent aider il faire naitre des circonstances heureuses, faut que le hazard nous serve Reamur : THE ROTIFEEA; OR WHEEL-ANIMALCULES BY C T HUDSON, LL.D Cantab ASSISTED BY P H GOSSE, F.R.S WITH ILLUSTRATIONS IN TWO VOLUMES PLATES LONDON LONGMANS, GKEEN, AND 1886 All rights reserved CO : Those viewless beings, Whose mansion the smallest particle is Of the impassive atmosphere, Enjoy and And live like That through their frame The man the minutest throb, slightest, faintest Is fixed, diffuses motion, and indispensable, As the majestic laws That rule yon rolling orbs Shelley Qui curiosus postulat totum suae Patere menti, ferre qui non suf&cit Mediocritatis conscientiam suse, Judex inicjuus, estimator est malus Suique naturseque ; nam rerum parens, Libauda tantum quse venit mortaUbue, Nos scire pauca, multa mirari jubet Geotius K3 I ... seen, the caudal points short, stout, and straight This was the form first recognized, is the form above described, and is by far the more common The other much larger, the articulation and the. .. those of the general shape, and of the size and position of the foot, are as follows The gastric glands are Ion" and cylindrical, and below them there are two pairs of short caeca attached to both. .. threads the two outer of which pass to the eyes, and the two inner to the sensitive The rest of the internal structure is bare spot on the tip of the proboscis (fig 2c) both obvious and normal The