226 The Management and Diseases of the Dog. 
amongst animals) thg part these tapeworms are destined 
to play in the economy of life is not merely remarkable, but 
altogether unique.” 
The first he notices is the cucumerine tapeworm (Tenia 
cucumerina): “It is a delicate and almost transparent tape- 
worm, measuring from ten to twenty inches in length.” 
This parasite is very common in English dogs, and, 
according to Krabbe, infests 48 per cent. of the dogs in 
Denmark, and 57 per cent. of the dogs in Iceland. The 
animals infect themselves in a singular manner. The 
joints of the worm, having escaped ger anum, readily 
crawl, as semi-independent creatures on the coat of the 
dog, chiefly on the back and side. The eggs thus dis- 
tributed are readily swallowed by the louse of the dog 
(Trichodectes latus). ~ 
In the body of the louse the six-hooked embryo, hitherto 
contained in the egg of the tapeworm, escapes the shell 
and becomes transformed into a minute cysticercus or 
louse-measle. When the dog is irritated by the lice, it 
attacks, bites, and frequently swallows the offending 
external parasite. In this way the louse-measle is trans- 
ferred to the dog’s intestinal canal, where, in course of time, 
it develops inte the sexually mature cucumerine tape- 
worm. 
Thus the mange-mite, or scab insect (as it is rather 
incorrectly termed), serves as the intermediary bearer of 
larval tapeworm, and forms an essential factor in the pro- 
duction of this particular species of cestode parasite. 
does, according to the experiments of Luschka, Leuckart, and others, 
in the organs of the domestic quadrupeds. 
“ It is of the greatest importance that careful and extended inquiries 
should be made as to the prevalence of these cysticerci in animals. It 
is evident from the observations of Kiichenmeister and others that 
many individuals of these species, forming extensive cystic tumours, 
are to be found in pigs, and not unfrequently there has been a confu- 
sion between cysticerci and echinococchi. Thus, in Ireland, the 
endemic cystic disease appears to be due to both these hydatids.” 
