W. S. Patton 
115 
birds, as well as the development in an invertebrate. Woodcock does 
not appear to have touched on this side of the question ; after all, 
this is where Schaudinn studied halteridium. If the difficulties in this 
country are too great, would it not have been better to have investigated 
this problem at Rovigno ? 
We do not wish to discourage Woodcock in his endeavours to confirm 
Schaudiun’s conclusions, but we must say this last piece of work is most 
unconvincing ; it is to say the least of it premature. Schaudinn’s work 
on Halteridium therefore, in our opinion, remains as yet unconfirmed. 
It has certainly had a far-reaching effect, and we would now like to see 
the problem investigated by an international commission, carrying on its 
work at Rovigno. 
In the seventh section Woodcock deals shortly with insect flagellates 
and their bearing on the evolution and phylogeny of trypanosomes. 
Leger’s (1902) definition of the genus Crithidia is again introduced, as 
well as his work on certain Herpetomonads. We have shown that this 
definition of the genus Crithidia is inaccurate, as it is based on the 
structure of the immature stages of Crithidia fasciculata ; many Herpeto¬ 
monads have a very similar appearance. Woodcock’s description of these 
important flagellates is extremely inadequate and out of date; the two 
genera are throughout confused, as they are in Leger’s original papers. 
Such a statement, as the following, will show that Woodcock’s knowledge 
of these parasites is mainly second haud : “ These forms ( Herpetomonas) 
are mostly parasitic in invertebrates which do not suck blood.” We 
know of at least two which are parasitic in blood-sucking insects, 
Herpetomonads of Culicines and Stomoxys. 
Woodcock next goes on to discuss the relation between these flagellates 
and the trypanosomes of vertebrates. It will be remembered that Leger 
(1902) expressed the opinion that the Crithidia of mosquitoes was most 
probably but a stage in the development of a Haemoflagellate, and 
that many more of these flagellates may eventually prove to be connected 
with blood parasites. Novy has however expressed the opinion that 
these insect flagellates are distinct from the blood trypanosomes. 
Ross (1906) has pointed out that he found the Herpetomonas of Culicines 
in the insects before they had fed on blood. We (1907) have recently 
been able to confirm these old observations of Ross, and have further 
pointed out that the larvae acquire the infection by ingesting cysts of 
the parasites passed out in the excreta of the adult insects. 
In summing up these opposing views, Woodcock attaches the utmost 
weight to the flagellates of the tsetse flies, which Minchin and others 
8—2 
