DR. T. S. COBBOLD ON ENTOZOA IN THE DOO. 295 



of an inch in length, and recorded as a female. It does not appear 

 to have since been met with. 



21. Filaria sanguinis. — Under this title I have a few more 

 words to say respecting the so-called haematozoa of MM. Grube 

 and Delafond. These investigators, some years back, examined 

 480 dogs, and in nearly five per cent, they found Pilarise in the 

 blood. The parasites were extremely minute, their diameter being 

 less than that of the dog's blood-corpuscle ! There can be no 

 doubt that they were larvae of some known, or unknown, species 

 of nematode. I have already hinted that these hsematozoa might 

 be the brood of Spiroptera sanguinolenta; yet in only one instance 

 were sexuaUy mature nematodes (of comparatively large size) 

 found in the heart. In this case the authors obtained six speci- 

 mens, " of which four were females and two males ; and they were 

 lodged in a large clot occupying the right ventricle." They 

 measured from g to | of an inch in length. MM. Grrube and 

 Delafond believed they had encountered a new species, and ac- 

 cordingly gave it the long name of Filaria papillosa hcematica 

 canis doinestici. In most of the dogs the entire circulatory system 

 does not appear to have been examined ; therefore it is quite pos- 

 sible that adult worms may have been present in more instances 

 than the one specified — perhaps in several. If such had been 

 proved to be the case, it might have been fair to have inferred a 

 genetic relation between the microscopic hsematozoa on the one 

 hand and the worms in the heart on the other. As the matter 

 now stands, we are in doubt as to the true adult representative of 

 these minute Filarice. With the verminiferous blood MM. Grrube 

 and Delafond performed a variety of curious experiments, but 

 they did not, so far as I am aware, employ any worm feedings. 

 They satisfied themselves that the hsematozoa could only live, as 

 such, in the blood itself, and they estimated that the verminous 

 dogs severally entertained from 11,000 to about 224,000 of these 

 larvse. In no case, however, had the infested animals appeared 

 to sufier inconvenience. 



Conclusion. — I have thus, in a condensed form, brought together 

 a large number of facts having reference to the frequency of 

 occurrence and variety of entozoa liable to infest the dog. The 

 way in which I have treated the subject is somewhat novel, my 

 object being to open up a new field of inquiry, bearing more less 

 closely on questions of public health. The full importance of 

 helminth ology in relation to entozootics can only be understood 

 by expositions of this kind, based upon investigations extending 



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