968 @, Rk. LEWIS. 
On NemMAtopE Hamatozoa inthe Doc. By T. R. Lewis, 
M.B., Staff Surgeon, H.M. British Forces, attached to the 
Sanitary Commissioner with the Government of India. 
(With Plate XIII, figs. 1 to 5.)! 
Wuen making a microscopical examination of some gland- 
tissue from the mesentery of a pariah dog, I observed that 
the sanguineous fluid squeezed out of the preparation on the 
slide contained numerous minute nematode worms in a state 
of great activity, and presenting at first sight a marked 
resemblance, both as to the character of their movements 
and their size, to the hematozoa formerly described as ex- 
isting in human blood. I had long been desirous of obtain- 
ing living specimens of a canine hematozoon for comparison 
with those found in man, though not with any very sanguine 
hope of thus pronouncing as to their identity, since it is well 
known that the embryos of many Filart@ of widely 
differing size and habitat present no appreciable difference 
either of size or form. 
With respect, however, to the particular heematozoa under 
consideration, I have no hesitation in pronouncing them to 
be totally distinct parasites. No indication whatever can 
be detected of this canine hematozoon being enclosed in 
any enveloping tube, such as the structureless hyaline 
tubular sac enclosing the human parasite. 
The internal structure of both is, however, pretty much 
alike ; in neither is there any visible differentiation of the 
reproductive organs, and only in a very minor degree of the 
alimentary tract; if anything, the canine parasite is perhaps 
the more advanced. 
Before attempting to arrive at any conclusion as to the 
probable or possible source of these embryos, it will be advis- 
able to describe briefly the pathological conditions which 
usually accompany their presence. ‘These, as far as may be 
inferred from very careful dissections of the twenty-seven 
dogs above referred to, may be described as follows : 
1. The most striking feature is the existence of fibrous- 
looking tumours, varying |from the size of a pea to 
that of a filbert or walnut, along the walls of the 
thoracic aorta and cesophagus, both tubes being 
affected, or only one. 
'“ Abstract of a Report on the Pathological Significance of Nematode 
Hematozoa,” forming an appendix to the ‘Tenth Annual Report of the 
Sanitary Commissiover with the Government of India.’ Caleutta, 1874. 
