49 



LOXODES ROSTRUM O. F. M. ■ 



My interest in this form was first awakened some years ago by 

 the diverse descriptions of its nuclear elements. This diversity 

 ranges from a single macro-nucleus, with its attached micro- 

 nucleus, to a multiplicity of the same. 



Wrzesniowski ('6i) and Kent ('82) describe and figure it as a 

 string of macro-nuclei with the micro-nuclei attached either to the 

 macro-nuclei or to the funiculi. 



Calkins ('01) figures this same string of nuclei as one of the 

 types of the Ciliata. 



Stein C7S), Claparede and Lachman ('60), Delage and 

 Herourd ('96) and Roux ('01) describe many disturbed macro- 

 nuclei, each with its attached micro-nucleus. 



Biitschli ('87) says there are from one to many unconnected 

 nuclei, according to the size of the animal. 



Stokes ('88) (L. vorax) and Engelmann ('62) (Drepanosoma 

 striatum) figure and describe Loxodes rostrum as having two 

 nuclei, subcentrally placed. Schewiakoff ('93) found it in the 

 Sandwich Islands with but a single oval nucleus, centrally placed. 



Since 1900, I have had hundreds of these forms from widely 

 separated localities in Louisiana, with fresh and brackisli water 

 habitat, and recently from the Gulf; all varying in size, from the 

 small colorless to the very large (625 microns) brown or golden- 

 colored ones. I have killed and stained hundreds of them with 

 the invariable result of demonstrating but two macro-nuclei, each 

 with an attached micro-nucleus. They were unconnected (shown 

 by isolation) and sub-central, one in each half of the animal. 

 The structure of the nuclei corresponded with the descriptions and 

 figures given by difterent authors — that is, they were round and 

 contained what resembled a nucleolus, thus imitating the typical 

 nucleus of a rhizopod. 



It is worthy of remark that, while it is usually difficult to 

 diflt'erentiate the micro-nuclei with picro-carmine, in these cases 

 they stained almost as brilliantly as the macro-nuclei. 



The conclusion then to be drawn from these facts is, that 

 Loxodes rostrum may have one, two or many unconnected nuclei, 

 or a series connected by funiculi, thus giving us four distinct types 

 of nuclei for a ciliate whose bodv form is constant. 



