100 Haemoflagellates, etc. 
Hirudinean host.” We consider there is a great deal of room for 
doubt. 
Woodcock next deals with Brumpt’s (1906) observations on the 
development of T. granulosum in Hemiclepsis mcirgincita. Brumpt has 
given no figures showing how this trypanosome develops into the pyriform 
parasites in the stomach of the leech; the description of these pear- 
shaped parasites in the leech clearly suggest a Grithidia similar to what 
we have seen in a species of Glossiphonia. Brumpt also states that the 
Herpetomonad forms of T. granulosum remain for months in the stomach 
of the leech; this fact again suggests a natural flagellate; we have found 
these flagellates remain for at least five months in the crop-diverticula 
of a leech. Brumpt states that the parasites in the leech eventually 
produce trypanosome-like forms which find their way to the foremost 
stomach coeca and proboscis sheath by the fifth day. With regard to 
this observation, Woodcock says, “these are the forms which are inocu¬ 
lated into the eel, becoming by simple elongation ordinary T. granulosum 
again.” Anyone reading this statement might be led to believe that 
this has been proved by Brumpt, whereas this is by no means the case. 
Before it can be proved that the flagellates in the stomach of the leech 
were actually injected into the blood of the eel, Brumpt must demonstrate 
the change from one parasite to the other; it is also necessary to show 
that the leech has not got any unchanged T. granulosum in its proboscis 
sheath. Throughout these observations of Brumpt we can find no 
reference to the exclusion of a natural flagellate of Hemiclepsis ; this is 
surely necessary. 
Woodcock gives a detailed account of Miss Robertson’s (1907) re¬ 
searches on a flagellate from the alimentary tract of Pontobdella muricata\ 
with her, he regards it as representing the developmental forms of T. raiae. 
According to Woodcock, Brumpt has found that T. raiae does develop in 
Pontobdella. In an earlier paper we (1908) pointed out, after reading 
Miss Robertson’s account of the life history of the flagellate of the leech, 
that the flagellate in question was most probably a true parasite of the 
leech. The structure of the adult flagellate and the method of develop¬ 
ment of its flagellum clearly suggest that this parasite is a true Grithidia 
—it is not at all unlike some of the tsetse fly crithidia—we have therefore 
named it G. robertsoni. All the evidence goes to show that this flagellate 
of Pontobdella is transmitted hereditarily. We can find nothing in Miss 
Robertson’s or Brumpt’s papers to show that it represents any stage in 
the evolution of T. raiae. Neither of these authors have attempted to 
exclude a natural flagellate of Pontobdella, -and before this has been done 
