ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 765 



refer tlie undulatory motion, which may be seen in a number of 

 individuals, as also in Trichomonas and Hexamitus, to a flagellum 

 attached to the anterior end of the body and directed backwards. 

 The normal number of flagella at the anterior end is four, but 

 they frequently adhere throughout their entire length. A mouth- 

 opening is placed rather to the side of this end of the body. With 

 regard to the phenomena of development, the author does not con- 

 sider it probable that the caudal appendage, after swelling consi- 

 derably, sometimes becomes detached and gives rise to a new indi- 

 vidual. The organisms die at 55° C Patients affected by the 

 parasites manifest acute or subacute diarrhoea. Grassi is unable to 

 regard this monad as the origin of the complaint, but considers its 

 appearance merely a circumstance attendant on the diarrhoea which is 

 produced by other causes ; in this connection it appears to him an 

 important fact that the liquid of the faeces forms one of the conditions 

 of the existence of the organism. He considers the possibility of its 

 occurrence in healthy subjects as not at present demonstrable. The 

 remedy applied was a solution of ipecacuanha (1^ grams in 100 of 

 water), but the ipecacuanha does not act fatally on the monads. No 

 diarrhoea is set up in dogs by administering to them infected fteces. 

 Other forms belonging to the subgenus are mentioned as having been 

 studied, viz. M. Gavice Gr. sp. ( = Trichom. cavice Dav. ?), M. coronellce 

 XL. sp. ( = Cercomonas colubrorum Ham. ?), M. anatis n. sp., M. hatra- 

 chorum n. sp. ( = Cercomonas intestinalis Ehr. ? Trichomonas batra- 

 chorum Per. ?). In the last-named monad, also, the undulatory 

 movement is explained as due, not to a vibrating fringe or a series of 

 cilia, but to a large flagellum placed at the anterior end. M. muris 

 n, sp. has but one flagellum at this part. M. lacertce viridis is another 

 new species. 



The genus Trichomonas is made by Grassi a subgenus of Monocerco- 

 monas and characterized as pilose, and thus is quite differently con- 

 stituted from the customary method. T. melolonthce n. sp. is shortly 

 described, but from its clothing of hair-like, immobile processes 

 appears to bear a closer relation to Mallomonas Perty. Although 

 more than 100 women were examined, Trichomonas vaginalis Donn. 

 was not met with= Monads were only once found in the mouth. 



Betorfomonas, a third subgenus of Monocercomonas, is character- 

 ized by its retort-like shape, and a species, B. gryllotalpce, is shortly 

 described from Gryllotalpa. 



The fourth subgenus, Schedoacercomonas, " similarly without caudal 

 appendage," appears with four species, S. gryllotalpce, S. melolonthce, 

 S. cavice nn. spp., and S. muscoe domesticce ( = Cercomonas muscce domes- 

 ticce Barnett). The genus Dicercomonas is distinguished from Mono- 

 cercomonas by the bifurcate caudal appendage, and is divided into two 

 subgenera, Monomorphus "appearing in a single form," and Dimorphus 

 " appearing in a double form." (From the description of D. muris, 

 the double form appears to mean nothing more than the difference in 

 form which the monad assumes when seen from different sides). 

 Monomorphus is based on the well-known Hexamita ranarum Duj., 

 which is said probably to possess six anterior flagella, and in which 



Ser. 2.— Vol. I. 3 E 



