CO THE ROTIFEEA. 



Genus STEPHANOCEROS, Ehrenberg. 



GEN. ClI. Lobes lo7ig, slender, erect, convergent; setae set diagonally on the lobes 

 in parallel bands ; foot terminated by an adJiesive cup. 



S. EiCHHOENii, Ehrenberg. 



(PI. IV. fig. 1.) 



Stcphanoccros Eichhoniii . . Ehrenberg, Die Infus. 1838, p. 400, Taf. xlv. fig. 2. 



„ ,, . . . Dujardin, Hist. Nat. Zooph. 1841, p. (;12, pi. xix. tig. 8. 



„ „ . . . Gosse, Piyjufar Set. iicy. vol. i. 1802, p. 30,pl. iii. anil iv. 



Stcplianoccros glacialis . . . I'eity, Zicr KcniUniss Jdeinst. Lehcnsf. 1852, p. 47, Tab. i. 



fig. 1. 

 Stc2>lui>wccivs Eichliornii . ■ Leyilig, Ucb.d. BmkI. liadcrth. Ifiii I, p.'), Taf. i. figs. 1-i. 

 ,, ,, . . . rritcliard. Infusoria, 1861, p. GC8, j)!. xxxii. fig. 383, 



pi. xxxvii. figs. 1-4. 

 „ „ . . . Cubitt, Mon. Micr. J. vol. iii. 1870, p. 240, pi. lii. 



„ ,, . . . Newlin Peirce, Proc. Acad. Nat. Sci. Pa. 1875, p. 121. 



„ „ . . . Bosscter, /. Hoy. Micr. Sac. 2 Ser. vol. iv. 1884, p. 1G9, 



pi. V. figs. 1-3. 



Anyone v.lio has seen Stcphanoccros favourably placed, and properly lighted, can 

 well understand the enthusiasm with which Eichhorn relates its discovery ' ; for it is a 

 lovely creature, and as strange as it is beautiful. A small pear-shaped body, whose 

 rich green and brown hues glow beneath a glistening surface, is lightly perched on a 

 tapering stalk, and crowned with a diadem of the daintiest plumes : while the whole is 

 sot in a clouded crystal vase of quaint shape and delicate texture. The tube is denser 

 tliaii it is in the Floscules, is more symmetrical in shape, and is continuous in sub- 

 stance from its outer surface almost to the creature's body. If an empty tube be 

 examined, it will be found that it has a central hollow, which the body and foot will 

 exactly fdl. 



j\Ir. Gosse and Dr. Jlantell have each seen a young Stephanoceros bore its way 

 through its parent's tube by means of its cilia ; just as I have several times seen young 

 Floscules do. The material, therefore, of which it is composed, must be of the flimsiest 

 kind. The commencement of the formation of the tube has been described by Mr. Gosse 

 [loc. cit.) as follows : " A specimoi, which was hatched under my eye, swam for ten 

 minutes, and then became permanently attached to the upper glass of the box, so that it 

 was vertical in its position, with the foot next to the eye ; a favourable aspect for 

 observing the development of the case. It presently began to dilate its body ; and, iu 

 about five minutes from its attachment, I perceived a distinct filmy ring around it, per- 

 fectly circular, whose diameter was about twice that of the body (PI. IV. lig. 8). The 

 little animal now began to lean over to one side, and the ring soon had another segment 

 additional, leaning in the same direction (fig. 9). The case, for such it was, looked like 

 two broad hoops of glass, each swollen in the middle and set one on the other but not 

 quite concentrically, at least to the eye of the observer. It was manifest that it was 

 produced from an excretion from the body, owing its form and size to the animal's mov- 

 ing round on the foot as on a pivot." 



Ehrenberg's drawing of Stephanoccros has certainly be'en taken from a crushed or 

 sicldy specimen, and, indeed, in tlie majority of cases its portrait has been drawn too 

 long after the creature had left its native haunts ; for when freshly caught and in 

 vigorous health it arches its live plumes so that its crown almost forms a sphere.''' The 



' P. 18, snpra. 



- Mr. Gosse has found that healthy specimens, removed from an aiinarium and inspected at once, 

 have their five arms more frequently produced into a cylindrical form, with Ihcir extremities incurved, 

 than arched into a sphere. 



