6 14 Microscopic Organisms in Blood of Man and Animals. [part hi. 



They were not in the least afifected on the addition of half per cent, salt-solution, 

 and continued to manifest active movements in it for from 6 to 8 hours. A drop of 

 blood containing numerous hsematozoa was placed on the slide arranged for the 

 application of electricity ; and an induced current of considerable force was passed 

 through it for two hours without the slightest appreciable effect on the filarise being 

 observed. As the current applied was stronger than could be tolerated by a man for 

 any lengthened period, it would seem that the application of such a remedial agent 

 to persons affected with organisms of a like character is not likely to be followed by 

 any satisfactory results. 



The blood of several of the crows examined was, when perfectly fresh, strained 

 through linen, but no parental form was caught on the strainer, nor were any ova to 

 be detected. 



In Solipeds — the horse, ass, mule, etc. — aneurismal dilatations of the mesenteric 

 arteries are very commonly observed, the result of an arteritis set up by the palisade 

 worm (Sclerostomum equinum) during one of the stages of its growth. As, however, 

 it does not appear to take up its abode in the blood itself, the matter does not call 

 for further reference here. It would seem, however, that occasionally the blood of 

 the horse does contain bond Jlde nematoid hsematozoa. Leuckart * refers to a case 

 of the kind as having been observed by Wedl in which the nematoid haematozoa were 

 associated with the presence in the abdominal cavity of Filaria papillosa, the ordinary 

 worm of the anterior chamber of the eye in horses, etc. ; and Sonsino t found three 

 minute nematodes in the blood which was drawn from the jugular vein of a horse. 

 They were '23 mm. in length, the length being to the width as 37 to 1, and in general 

 appearance they resembled the hsematozoa of the crow. 



Of all animals which have been found to harbour hsematozoa, the dog, perhaps, 

 takes the first place. Dogs affected in this manner have been observed in nearly all 

 parts of the world, notably in China, India, and some of the southern parts of Europe. 

 It is, moreover, probable that the embryos of different species of nematoids are found 

 in this animal's circulation : that mature helminths of different species are found in 

 it is a well-ascertained fact. 



The interest in this subject dates from the observations which were made more 

 than twenty-five years ago by MM. Grruby and Delafond, which went to show that 4 

 to 5 per cent, of the dogs in France harboured microscopic nematodes in their blood. 

 In a paper entitled "The Pathological Significance of Nematode Hsematozoa" published 

 by myself in 1874,| it was pointed out that more than a third of the pariah dogs of 

 this country are similarly affected; and Dr. Patrick Manson has shown that this kind 



* Op. cit., vol. ii, p. 635. 



t Op. cit. 



j Tenth Annual Report of the Sanitary Commissioner with the Government of India, App. B, 1874 ; Indian 

 Annals of Medical Science, No. XXXIV, JUI7 1876 ; also, in part, in Quarterly Joui-nal of Microscopical Science, 

 1875, page 533 of this volume. 



