W. S. Patton 
09 
contrary, that recent researches are in favour of vertebrate trypanosomes 
having specific alternate invertebrate hosts, we hope to show that the 
views of the American observers hold good at the present time. 
Woodcock then proceeds to describe the researches which support his 
contention. 
According to Leger (1904), Trypanoplasma varium, in the blood of 
the loach, may be differentiated into ordinary (indifferent) forms and 
large, more granular (probably female) parasites. When these parasites 
were ingested by Hemiclepsis sp. ? the indifferent forms degenerated and 
died out, the female parasites however became more massive and 
exhibited nuclear changes which Leger thinks suggest a sexual process. 
After some days the intestine of the leech contained numerous little 
narrow trypanoplasmes, some of which were filiform (male), while others 
had a kind of beak which made them resemble trypanosomes. These 
observations were published in a preliminai'y note without figures so 
that we are unable to refer to the actual appearances of the parasites. 
We know of no subsequent work confirming Leger’s observations. In 
this preliminary note we are not told how Trypanoplasma varium 
developed into the male forms he describes from the leech; where the 
evolution of the one begins and the other ends is not at all clear. If 
these changes take place naturally in the leech it is surely possible to 
trace all the stages from the unchanged female forms up to the forma¬ 
tion of the narrow trypanoplasmes and the parasites with beak-like 
processes; if not there must be some other explanation for the origin of 
these forms. We can find no reference to the possibility of Hemiclepsis 
being infected with a natural flagellate. We are therefore unable to 
accept this developmental cycle of Trypanoplasma varium as proved. 
Woodcock next describes Leger’s (1904) observations on Trypano- 
somabarbatulae in another leech, Piscicola. Leger, it will be remembered, 
draws particular attention to the formation of male, female and neutral 
forms of this parasite and says they correspond exactly with Schaudinn’s 
three types. Woodcock states that these types are sharply differentiated 
in the invertebrate host and less so in the vertebrate. Here again we 
fail to see what connection these so-called male, female and indifferent 
forms in the leech have to do with T. barbatulae. The existence of these 
forms is certainly not proved in Leger’s paper, a natural flagellate of 
Piscicola is not referred to, nor is it shown how the trypanosome gets 
back again to the fish. In his original article on the Haernoflagellates 
Woodcock says, “the above-stated facts however hardly leave room for 
doubt that both these piscine trypanosomes have a true alternating 
