6o6 ORDER HETEROTRICHA. 



blance to, and possible specific identity with, the fresh water Tint'mnus (Tintin- 

 nidium) fluviatihs of Stein, but are at the same time altogether silent upon the 

 subject of its either attached or pelagic habits. 



Tintinnus obliquus, C. & L. PL. XXXI. FIG. 26. 



Lorica elongate, subcylindrical, transparent, homogeneous, seven or 

 eight times as long as broad, narrower and conical posteriorly, the anterior 

 margin even, straight ; animalcule conical, its anterior margin very obliquely 

 truncate, projecting, when extended, to nearly its entire length beyond the 

 anterior margin of its lorica. Length of lorica 1-150". 



HAB. Salt water : coast of Norway (C. & L.). 



This species differs from T. inquilinus in the oblique contour of the peristomal 

 margin of the animalcule only, and in the regular conical shape of the posterior 

 extremity of the lorica; this structure is likewise proportionally much more elongate. 

 In common with the last-named type the animalcule is often found with the pedicle 

 attached high up on one side of the lorica ; Lachmann's sketch represents an 

 example so fixed to the centre of the interior of its sheath, and with the body almost 

 entirely extruded from the aperture. 



Tintinnus amphora, C. & L. PL. XXXI. FIG. 12. 



Lorica transparent, homogeneous, elongate vase-shaped, about three and 

 a half times as long as broad, inflated most a little below the centre, the 

 anterior margin even, circular, slightly everted, followed by a narrower 

 neck-like portion. Animalcule undescribed. Length of lorica 1-125" to 

 1-80". HAB. Salt water : Sartoro, Norway (C. & L.). 



No description of the living animalcule of this species has been recorded, but a 

 motionless stalked cyst was on several occasions observed within the lorica. Some- 

 times this cyst contained a single granular body, while at other times it was broken 

 up into numerous smaller granular spherules, each of which contained a colourless 

 vesicle. Claparede and Lachmann were undecided whether or not to regard these 

 cysts as intruding organisms or as encysted conditions of the original inhabitants. 

 The latter interpretation may, however, probably be accepted, taking into consider- 

 ation their stalked condition and the almost universal occurrence of an encysted 

 stage throughout the whole class of infusorial animalcules. Similar encysted bodies 

 were observed by these authorities in connection with various other members of the 

 genus Tintinnus. 



Tintinnus acuminatus, C. & L. PL. XXXI. FIG. 14. 



Lorica diaphanous, homogeneous, elongate-cylindrical, ten or twelve 

 times as long as broad, the posterior extremity acuminately pointed, the 

 anterior margin even, everted. Animalcule not observed. Length of lorica 

 i -80''. HAB. Salt water : Norwegian coast (C. & L.). 



No account of this animalcule has been recorded ; the lorica, while most nearly 

 resembling that of T. subulatus, differs from that species in its everted and non- 

 annulate anterior margin and in its acuminate posterior termination, which is 

 described as being facetted in an elongate-pyramidal manner. 



Tintinnus Steenstrupii, C. & L. PL. XXXI. FIG. 20. 



Lorica diaphanous, homogeneous, subcylindrical, elongate vase-shaped, 

 seven or eight times as long as broad ; the posterior extremity slightly 



