Prot(^Z()(i Parasitic in Frogs. 591 



while in Fig. 1-i division of the nucleus is completed and the 

 nuclei have taken up their adult position. 



In the posterior portion of the body excretory organs are 

 present in the form of a great number of vacuoles, forming 

 qiiite a network and extending from about the middle of the 

 body to the posterior extremity. (Figs. 10 and 15.) 



B. Flagellata. 



The commonest flagellate form present in the intestine is one 

 which I take to be identical with the Euglenoidina from Rana 

 temporaria and Bufo vulgaris described by Dobell, viz., 

 Cojfr(j/ni)tias suhtilis. It is found in countless numbers in 

 cultures that have been standing for some days, and is present 

 in all the species of frog examined. On account of its small 

 size I have not been able to make out all the minute details 

 of structure, nor have I traced through the different .stages of 

 its life history, but its general form and movements agree so 

 closely with Copromonas suhtilis that I think we may say it is 

 identical (Fig. 16). A few individuals were observed undergoing 

 longitudinal division (Fig. 17), and also some in conjmifation 

 (Fig. 18). 



Occurring along with these but in far smaller numbers is a 

 similar form which is more rectangular in outline and slightly 

 longer. I have not succeeded in obtaining any of these 

 mounted on the slide, but in the living state they appear very 

 similar in structure to the oval forms. 



The other flagellate forms present in the large intestine are 

 the trichomonads. These I have found in large numbers in four 

 out of the five species of frog examined, there being none in 

 Hyla ewingii. This need not mean, however, that they are 

 absent in this species altogether, for I may have missed them 

 in examining the culture, or they may have been absent only 

 from the particular individiuds under inspection, l^obell (7) 

 says as regards the trichomonads : '' It has hitherto been uni- 

 versally supposed that but one trichomonad occurs in frogs, 

 namely Trichomonas hatrachorum, Perty. There are, however, 

 in reality two, a Trichomonas and a Trirhomastir." The latter 

 is represented by Trichoynastix hatrachorum, Dobell, which he 

 jroes on to describe. 



