PROTOMONADINA 279 



T. lewisi (Kent) (Figs. 120; 124, g). In blood of various species of 

 rat; widely distributed; about 25m long; very active; slender; with 

 a long flagellum; transmitted by the flea, Ceratophyllus fasciaius, in 

 which the organism undergoes changes (Fig. 120); when a rat swal- 

 lows freshly voided faecal matter containing the organisms, it be- 

 comes infected. 



T. duttoni Thiroux. In the mouse; similar to T. lewisi, but rats are 

 said not to be susceptible, hence considered as a distinct species; 

 transmission by fleas. 



T. peromysci Watson. Similar to T. lewisi; in Canadian deer mice, 

 Peromyscus maniculatus and others. 



T. nahiasi Railliet. Similar to T. lewisi; in rabbits, Lepus do- 

 mesticus and L. cuniculus. 



T. paddae Laveran and Mesnil. In Java sparrow, Munia oryzi- 

 vora. 



T. noctuae (Schaudinn). In the little owl, Athene noctua. 



Numerous other species are known. 



Crocodiles, snakes, and turtles are also hosts for Trypanosoma. 

 Transmission by blood-sucking arthropods or leeches. 



T. rotatorium (Meyer) (Fig. 125, a). In tadpoles and adults of 

 various species of frog; between a slender form with a long projecting 

 flagellum measuring about SSju long and a very broad one without 

 free portion of flagellum, various intermediate forms are to be 

 noted in a single host; blood vessels of internal organs, such as kid- 

 neys, contain more individuals than the peripheral vessels; nucleus 

 central, hard to stain; blepharoplast small; undulating membrane 

 highly developed; myonemes prominent; multiplication by longi- 

 tudinal fission; the leech, Placohdella marginata, has been found to 

 be the transmitter in some localities 



T. inopinatum Sergent and Sergent (Fig. 125, h). In blood of vari- 

 ous frogs; slender; 12-20 fj. long; larger forms 30-35m long; blepharo- 

 plast comparatively large; transmitted by leeches. 



Numerous species of Trypanosoma have been reported from the 

 frog, but specific identification is difficult; it is better and safer 

 to hold that they belong to one of the 2 species mentioned above 

 until their development and transmission become known. 



T. diemyctyli Tobey (Fig. 125, c). In blood of the newt, Triturus 

 viridescens ; a comparatively large form; slender; about 50^ by 2-5/i; 

 flagellum 20-25m long; with well developed undulating membrane. 



Both fresh and salt water fish are hosts to different species of 

 trypanosomes; what effect these parasites exercise upon the host 



