GENUS LA CR YMA RIA . 517 



extremity abruptly truncate ; contractile vesicles multiple, lineally disposed. 

 Length of body when most extended 1-24", retracted 1-60". 

 HAB. Salt water. 



The rigid annular border surrounding the apical extremity in this form would 

 seem to take the place of the conical prominence in the ordinary species, unless it is 

 that Cohn's figure and description apply to examples in which at the time of 

 examination this usually conspicuous structure was concealed by invagination. 

 Although a single contractile vesicle only is seen in the figure here reproduced 

 from Cohn's original account of this species,* the two other examples delineated by 

 this authority exhibit respectively two and eight of these structures, and which in the 

 last instance are disposed at even intervals throughout the centre of the thicker 

 central region of the body. In one example the endoplasmic layer has a vacuolar 

 or reticulate aspect somewhat analogous to that of Trachdius ovum. 



Trachelocerca tenuicollis, Quenn. 



Body elongate-lanceolate, pointed posteriorly ; neck long and very 

 slender, scarcely dilated at the apex ; cuticular surface finely ciliate, feebly 

 striate longitudinally ; contractile vesicle posteriorly situated ; endoplast 

 subcentral. Length in extension 1-75". HAB. Salt water. 



GENUS II. LACRYMARIA, Ehrenberg. 



Animalcules free-swimming, more or less cylindrical, clavate or flask- 

 shaped, moderately elastic, the anterior end narrowest, the apical extremity 

 conical in outline, and separated from the remaining portion of the body by 

 an annular constriction, the intervening region not produced into a separate, 

 slender, and highly elastic neck-like region, as in Trachelocerca ; oral aperture 

 surrounded by one or more ciliary circlets, perforating the apical extremity of 

 the anterior conical prolongation ; the cuticular surface finely and entirely 

 ciliate ; contractile vesicle single, postero-terminal ; anal aperture situated 

 immediately behind the contractile vesicle. Mostly inhabiting salt water. 



The Lacrymaria lagenula of Claparede and Lachmann is here adopted as the 

 type-form of this genus, to which two additional forms possessing the same broad 

 general characters are here added. The Lacrymaria proteus, L. olor, L. gutta, 

 L. rugosa, L. tornatilis, and L. farcta, of Ehrenberg, Perty, and Dujardin, are long 

 flexible-necked animalcules, referable, so far as it is possible to identify them, to the 

 genera Trachelocerca and Amphileptus. 



Lacrymaria lagenula, C. & L. PL. XXVII. FIG. 34. 



Body clavate or flask-shaped, attenuate anteriorly, nearly four times as 

 long as broad ; cuticular surface obliquely striate, finely and entirely ciliate, 

 a single circlet 'of longer cilia surrounding the oral region ; contractile vesicle 

 single, spherical, postero-terminal ; endoplast elongate-oval, subcentral. 

 Length of body 1-350". HAB. Salt water : Norwegian coast (C. & L.). 



As suggested by its discoverers, the contour of this animalcule corresponds 

 remarkably with that of a soda-water bottle, the posterior inflated portion answering 



'Neue Infusorien im Seeaquarium," 'Zeitschrift fur Wissenschaftliche Zoologie,' Bd. xvi., 1866. 



