OF THE VORTICELLINA. 



591 



its lips, like (si parva licet componere 

 magnis) a camel can its palate". 1-430" ; 

 tree 1-24". 



The process above alluded to by 

 Ehrenberg as protruded from the head 

 of this animal is undoubtedly the sort of 

 under lip alluded to b}' Stein in his ac- 

 count of Opercular ia (see next page). 

 This author, again, confirms Ehrenberg in 

 his doubt as to the position of this species, 

 and shows that it is an Opcrcularia. 



^.Botri/tis. — Verysmall,oyate,crowned 

 ■v\-ith cilia. They resemble grapes upon 

 a simple hyaline pedicle. This species 

 together with E. Arabica and Carchesimn 

 pygmceum are, in Stein's opinion, not 

 really distinct species, but difi'erent 

 phases of the same animalcule. 1-2400"; 

 tree 1-240" (see p. 589, last line). 



E. vegetans ( Volvox vegetans, M.). — 

 Very smaU, oyate, crowned with cilia 

 (?) ; disposed in clusters, like the pre- 

 ceding, upon a branched pedicle, of a 

 yeUow colour. When the water con- 

 taining this species is coloured with 

 indigo, strong cm-rents are seen at the 

 front or head of each animalcule, evi- 

 dently caused by a yibratile organ ; but 

 whether this is a ^i-eath of cilia or a 

 simple proboscis, is undetermined ; if a 

 proboscis, this creature would belong to 

 the Monads, where it would form the 

 type of a new genus. In river-water. 

 i-'Sm" ; tree 1-140". 



Brightwell says (Fauna Infusoria of 

 Norfolk, 1848) that the armed or oval ani- 

 malcules are furnished with a long fila- 

 ment, that, when the M^ater is shallow, 

 they detach themselves, and swim about 

 with a revolving motion. The organ of 

 motion he states to be a long filament 

 (proboscis) ; if so, the animal is not an 

 EpistyUs. Stein treats it also as a very 

 doubtful Ejnstylis. 



E. parasitica. — Small, conical, campa- 

 nulate, and solitary ; pedicle simple and 

 smooth. Upon Zoobotryon pellucidus. 

 1-570" ; with pedicle 1-120" to 1-24". 



E. Arabica. — Small, oval, campanu- 

 late ; pedicle but little branched, smooth, 

 and hyaline. In the Red Sea. Size of 

 tree 1-140". 



This species, as well as E. Botrytis and 

 Carchesium pygmceum, are adduced by 

 Stein as insufficiently marked, and re- 

 fen-ed by him to the yoimg and incom- 

 plete forms of other species. 



E. Barba. — Ovate, oblong, white ; 

 branches dichotomous ; longitudinally and 

 regularly striated. On larvfe of insects. 



E. beiberiformis-= Opercnlaria berbe- 

 rina (Stein) (xxix. 4). — Oblong, sub- 



cylindrical, white ; stem dichotomous, 

 articidated, and striated, its divisions 

 dilated at their apices. Parasitic, Berlin. 



This is not, as Stein shows, a species 

 of Epistylis, but of Ojjercularia, under 

 which we shall introduce it ^dth the de- 

 scriptive account this able writer supplies. 



E. euchlora. — Oblong, rather expanded 

 in front, with green ova ; stem dichoto- 

 mous. 1-13" in height, smooth. Para- 

 sitic on Planorbis cornea, Berlin. 



E. pavonina. — Ver}- large, helmet- 

 shaped, elongated in front; stem very 

 high, dichotomous, striated, and hence, 

 by decomposing light, displays many 

 hues. Often 1-3" in height. Berlin. 



E. crassicollis (Stein) (xxx. 11). — 

 Stem of considerable height, acutely and 

 dichotomously branched so that the seve- 

 ral zooids it supports are brought nearly 

 on the same level (corymbose). Branches 

 smooth, transparent, straight, and of 

 equal thickness. In some specimens 

 transverse lines or joints occur; and the 

 stem is frequently dilated at the point 

 of divergence of its branches. Animal- 

 cules ovate, contracted posteriorly, and 

 also in a slighter degree anteriorlj'. The 

 annulated, hoop-like periston! surmounts 

 the body, ha^-ing a rather smaller dia- 

 meter. The rotary disc is convex, but 

 rises only slightly above the periston!. 

 The cesophagus and its intestine-like 

 continuation curve backward almost to 

 the posterior extremity of the body. 

 The contractile space lies close to the 

 lower end of the stem of the rotary 

 organ ; the nucleus is hoi^seshoe-shaped. 

 Contents white, frequently with specks 

 of red. Largest specii!!ens 1-240" in 

 length, and 1-480" in width. Occurs on 

 the bristles ^of the hind feet and of the 

 jaws of Entomostraca. 



E, brancliiophila (Perty). — Spherical, 

 with a truncate base ; colour grey. Stem 

 and branches colourless and smooth. 

 1-360"; length of polypidom 1-96". The 

 animalcules are sparse in reference to the 

 dimensions of the steii! : the latter often 

 rugose at its jimction with the animal it 

 suppoii;s. When the stem coi!tracts it 

 does so only on oi!e side, and not com- 

 pletely across. Both this desciiption 

 and the figures given in illustration by 

 Perty are, as Stein observes, insufficient 

 to characterize the species. The latter 

 writer retains the name, however, for an 

 Epistylis having a relatively thick stem, 

 of moderate height, repeatedly forked, 

 finely striated and somewhat curved. Of 

 the two branches resulting froi!! a bifur- 

 cation, one attains a much greater length 



