51 



In all species but one, the contractile vacuole is single and pos- 

 terior, while Calkins ('02) describes and figures several in the 

 posterior extremity of L. infusionum. I have noted above, a condi- 

 tion which tends to produce an accumulation of clear vacuoles in 

 the posterior extremity, and the figures of L. velifer, striatus and 

 intermcdius contain several such vacuoles in that extremity, in 

 addition to the contractile one. Cohn (L. velifer) did not see the 

 nucleus, Gourret & Roeser (L. intermedius) describe and figure 

 two central nuclei, while the other three authors describe and fig- 

 ure a single central nucleus. The two nuclei of L. intermedius may 

 be the initial stage of division, or if not, it should not weigh against 

 the identity of species (Loxodes rostrum, vide supra). 



The caudal seta, which is not always very distinct, is mentioned 

 for all but L. velifer, and Cohn's reason for not noting it may be 

 similar to mine for not seeing the double membrane when I first 

 met L. ornatus (vide supra). 



Lemhiis striatus and L. intermedius seem to be well dififerent- 

 iated from all the other species by what is described and figured 

 as transverse striae on the body, but if one will scan the figures 

 (L. striatus Fab.-Dom. '85, PI. XXIX, fig. 6; L. intermedius, G. 

 & R. '86, PI. XXX, figs. 2 & 3) it will be seen that these striae are 

 coincident with the annulations, and that it is highly probable that 

 they represent these annulations strongly accentuated. 



BLEPHAROSTOMA PIGERRIMA Cohn Sp. 



In the brackish waters of Lakes Pontchartrain and Borgne, and 

 recently in the Gulf, I have met with a ciliate, the features of which 

 have led me to place it in the genus Blepharostoma as erected by 

 Schewiakoff ('93). Its body is pliant, very transparent, somewhat 

 fusiform and about twice as long as its greatest central width. It 

 is very much compressed laterally, this compression giving its dor- 

 sal and ventral surfaces a width of about one-third its depth. Its 

 anterior extremity is diagonally. truncated towards the ventral sur- 

 face and occupies about one-third of the body-length, constituting 

 an oval oral fossa, at the lower extremity of which the oral aper- 

 ture is situated. 



The body is sparsely covered with fairly long and slowly-moving 

 cilia. The entire edge of the oral fossa, excepting a small part in 

 the immediate vicinity of the oral aperture, is provided with a sin- 

 gle row of cilia which are distinctly longer and heavier than those 

 covering the rest of the body. These cilia are always bent towards 

 the oral aperture and have a movement which directs the food to 

 this aperture as well as assisting in the locomotion of the animal. 



