6i2 Microscopic Organisms in Blood of Man and Animals. [part hi. 



tion is Distomum hcematohium, a fluke-parasite discovered by Bilharz * in the venous 

 system of the abdominal viscera of persons in Egypt in 1851 ; in 1857 by Dr. Spencer 

 Cobbold in the portal vein of a monkey ;t and lately by Dr. Sonsino $ in like situations 

 in oxen and sheep. These parasites appear to affect about a third of the entire 

 population of some parts of Egypt. The female is a filiform parasite some- 

 thing less than an inch in length ; and the male thicker, but only a little 

 than half the length of the female. The anatomy and the pathological signifi- 

 cance of these worms are so well known that it is not necessary to give details, 

 especially as nearly every text-book of medicine supplies full information regarding 

 them. 



B— Nematoid Hsematozoa of Animals. 



The nematoid hsematozoa are far more numerous, although to some extent the 

 number has been increased by the circumstance that nematoid embryos which have 

 accidentally got into the circulation have been classified as hsematozoa, though, in 

 such cases, the blood can scarcely be considered as their normal habitat. 



These parasites have been found in nearly all classes of animals either in the 

 mature state, or as embryos, or as both combined. 



Not uncommonly the parents may be found in the tissues and the embryos in the 

 blood. Vogt, for example, found two large filarise, over two inches in length, in the 

 ventral cavity of a frog. These were distended with ova and embryos, the latter being 

 also found in the blood of the frog. § 



Under the designation Filaria cordis phocce M. Joly describes numerous female 

 nematoid parasites which he had discovered in the heart of a seal, 6'' to 8'' in length, 

 and about " in width, and which were stuffed with ova and embryos. Towards the 

 anterior third of the body the latter were free and measured from -^-^jy" to -^l-^" (-06 to 

 •07 mm.) in length. The male was not seen.|| 



Dr. Cobbold also describes a parasite, Filaria hebeta, which was found in the heart 

 of a seal. The length of the female in this case also was 6 inches; that of the 

 male, distinguished by the possession of a spirally curved tail, was up to 4 

 inches. The embryos were considerably larger than the measurements given by M. Joly 

 as those of his parasites, being ^", and about the width of a human red blood- 

 eorpuscle.lf 



Wedl found a filaria with a broad head and filamentous tail in the blood of a whale, 

 together with a peculiar body (" aus acht in einander geschobenen Eingen bestehende 

 Korperchen ") double the length of a blood-corpuscle, 



 Zeitgchr.fil/rwissen. Zoologie. Band IV, 1853. 

 f " Entozoa : an Introduction to the Study of Helminthology," 1864. 

 j " Sugli Ematozoi come contributo alia Fauna Entozoica Egiziana," 1877. 



§ " Archiv. fur Anat. und Physiol.," 1842, S. 189 ; cited by Leuckart, " Die Menschlichen Parasiten ; " Band I, 

 p. 52. 



II AnnaU and Magazine of Natural History, yoI. I, 1858. 

 il Proceedings of the Zoological Society, Nov. 1873, p. 741. 



