INVASION OF BLOOD BY MASTIGOPHORA 271 



(1909) noted that Copromonas major occurred coprozoically in lizard's 

 faeces, and that occasionally it occurred in the unencysted stage in the 

 lizard's intestine. Some flagellates which are more truly parasitic, such 

 as Trichomonas, are not only readily culturable in artificial media, but may 

 survive for long periods in faeces outside the body, while others, such as 

 Giardia, quickly die after leaving the body. Other forms, such as Bodo 

 and Cerco7nonas, rarely if ever occur in the intestine in any but the en- 

 cysted stages, but they are the commonest forms to develop coprozoically 

 in stale faeces. 



INVASION OF BLOOD-STREAM BY INTESTINAL MASTIGOPHORA. 



Between the forms which are more specially adapted to life in the 

 intestine, like Giardia and Trichomonas, and the true parasitic flagellates 

 belonging to the Trypanosomidae and Cryptobiidae various gradations 

 occur. Several observers have found that intestinal flagellates may 

 occasionally invade the blood-stream. Danilewsky (1889) noted that 

 the intestinal Hexamita sometimes invaded the blood vessels of the 

 edible frog and tortoise. Labbe (1894), and more recently Ponselle (1919), 

 made a similar observation in the case of the frog. The latter was able 

 to produce a blood infection of Rana temporaria by inoculating blood 

 containing Hexamita from an infected edible frog. Labbe (1894) also 

 stated that he had seen a Bodo and Hexamita in the blood of a lizard 

 {Lacerta sp.), while Hexamita has been seen in the blood of the toad 

 {Bufo calamita) in large numbers by Lavier and Galliard (1925). Lan- 

 franchi (1908) saw Trichomonas in the blood of a pigeon. Gonder (19106) 

 observed Giardia in the blood of a falcon (Elamus coeruleus) which had 

 been shot. It is possible that in this case the blood was contaminated 

 from a wounded intestine. Martoglio (1917) saw a Tetratrichomonas in the 

 blood of a fowl, while Chatton (1918a) observed a Eutrichomastix in the 

 blood of the gecko {Tarentola mauritanica) . Reichenow (1918) observed 

 the same flagellate in the blood of Lacerta muralis and L. viridis. He 

 noted that the mites which fed on the lizards also became infected, and 

 that young lizards were able to acquire an intestinal infection by eating 

 infected mites. During the examination of the blood of animals which 

 had died in the Zoological Gardens in London, Plimmer (1912a) on 

 several occasions found intestinal flagellates in the blood-films. He 

 observed Hexamita in the blood of tortoises {Cyclemys trifasciata, Cistudo 

 Carolina, Testudo angulata), and Trichomonas in the blood of snakes 

 (Coluber leopardinus, Naia tripudians, Heterodon simus, Python sebce). 

 It is possible that in some of these cases the flagellates appeared in the 

 blood-films as a result of damage to the intestine at the post-mortem 

 examination. Sangiorgi (1922) states that he observed a Trichomonas 



