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and most of them requiring to pass through more than one host or 
individual before completing their life-history. 
One thing which they had learnt was their comparative harmless- 
ness ; for, though an individual might be attacked by them, and in 
some cases carry about in his body enormous numbers, it was only in 
a few, and under particular states of some Entozoa, that they 
proved fatal. In fact, people were often their hosts without either 
knowing it or feeling any inconvenience. 
While tapeworms and ascarides were generally only sources of 
inconvenience, one stage of the former was likely to be dangerous, Viz., 
the hydatid. The life-history of the common tape-worm was that 
of a long chain of joints, each of which was called a zooid, the 
anterior segment, forming the head, and a few following segments 
being barren, while the remainder became mature and capable of in- 
dependently producing eggs containing embryos furnished with hooks ; 
these embryos became metamorphosed into the cysticercal state, which, 
when aborted, formed the common hydatid. 
The dog acted as a preparatory host, and handed over, as in 
Iceland, the dangerous guest to his master. A dog voided in the 
drawing-room of a house the tape-worm he had in a bottle, any eggs 
from which, introduced into the human system, might have pro- 
duced the hydatid form and have caused fatal disease. 
Hardly an animal he had ever examined but revealed the presence 
of entozoa. In examining animals for entozoa the coats of the stomach 
' should be looked at, while hydatids would be found in the brain, 
liver, &c. 
_ Mr. Wonfor remarked that Dr. Cobbold had also taught them the 
lesson that meat infected by entozoa was rendered harmless by being 
properly cooked. They had also learnt that beef and mutton were as 
liable to the presence of entozoa as the pig. In the case of Trichina 
Spiralis, which had been so fatal when producing the disease trichiniasis, 
it was almost unknown among us, with a prejudice in favour of well- 
cooked meat : but common among those who indulged in raw bacon and 
semi-cooked pork. That the temperature of boiling killed the entozoon 
was a great satisfaction. 
He believed in all the cases where, after death, in this country, 
trichine had been detected, the individuals were unconscious through 
