239 
THE LEUCOCYTOZOA, 
A REJOINDER TO Mr C. M. WENYON. 
By ANNIE PORTER, B.Sc. 
In the last number of Parasitology (Yol. in. No. 1) Mr Wenyon has 
taken exception to an article of mine on the Leucocytozoa , published in 
Science Progress, October, 1909. It has been a matter of wonder to 
many protozoologists as well as to myself, why Mr Wenyon did not 
reply to my article in Science Progress itself, and thereby appeal to the 
readers whom he accuses me of having misled, for he states ( Para¬ 
sitology, , p. 65) that my “ survey of the group is inaccurate and 
contradictory.” 
The character of my article in Science Progress is well summed up 
in my concluding paragraph on p. 265. “ Such is a general survey of a 
very interesting group, the Leucocytozoa, which, perhaps, is not homo¬ 
geneous, as the forms in birds differ in some respects from those 
occurring in mammals. This survey is the first that has been attempted, 
and it is hoped that it may draw attention to and stimulate research 
upon an interesting group of parasites which are probably more nume¬ 
rous than we know at present. They should be searched for among 
reptiles, amphibia and fishes.” This paragraph, along with the major 
part of my article, Mr Wenyon has chosen largely to ignore. 
Mr Wenyon’s chief accusation is that I have confused the avian 
Leucocytozoa with the haemogregariniform parasites found in the leuco¬ 
cytes of mammals. This is grossly inaccurate, for on p. 264 of my article, 
I state that “as the structure and life-history of avian Leucocytozoa are 
still subjects of controversy, and as the name Leucocytozoon was first 
applied to the parasites of birds, and Lithe seems to restrict the name 
thereto, the generic name Leucocytogregarina might be used for the 
highly specialised parasites of mammalian leucocytes, which have a 
different habitat from the strict Haemogregariues of red corpuscles.” I 
think from the foregoing quotation, it will be quite obvious to my 
readers that I have not confused the avian and mammalian parasites, 
for both of which the name Leucocytozoa has been used by many 
authors, and it was necessary, in a somewhat popular article, to deal 
with all the parasites that had at any time been termed Leucocytozoa. 
