3o 6 
Internal Enemies . 
[May, 
course of three or four days they find their way into the 
smaller intestines, where, when met with, it is known as an 
intestinal trichina. Here the female, which is about 0*04 
to o‘io of an inch in length, produces living young to the 
number of 500 to 1000 or more, a process which occupies 
sometimes three weeks, and then dies. The young para- 
sites, which are scarcely one-twentieth of the size ol their 
mother, do not remain where they were born, but perforate 
the coats of the intestines, and in the space of about six 
days distribute themselves through the entire body of their 
host, especially the anterior portion. They seem especially 
to haunt the muscles which lie between the ribs, and those 
of the neck, the jaws, and the eyes. When they have found 
quarters to their satisfaction their wanderings cease, they 
attain the full stature of their parent, and are now known as 
muscle-trichinae. Their development occupies a space 01 
about two weeks. Having thus reached maturity we might 
expeCt that their new task would be the perpetuation of 
their species ; but nothing of the sort takes place : each 
trichina becomes encysted, coiling itself up something after 
the manner of an ammonite, and covering itself with a cal- 
careous layer or capsule. Here, then, it remains possibly 
for years, motionless but yet alive. In this state it is found 
in the flesh of the pig when slaughtered. There are yet 
two remarkable points to be noticed in connection with tn- 
chinised swine. The animals as a rule do not appear to 
suffer in any marked degree from the presence of these 
parasites. So much at least may be said, that they do not 
present a diseased appearance. This circumstance greatly 
increases the danger of the Trichina finding their way into 
human food. If the pigs when thus attacked became sickly, 
emaciated, &c., buyers and market inspectors might have 
their suspicions excited. But, save by microscopical exa- 
mination, there is no certain way of distinguishing the flesh 
of a trichinised pig from that of one that is perfectly sound. 
By what we might almost call a Satanic instinCt they never 
attack the heart of their viftim, in this respeCt resembling 
the ichneumon larvae, which, while devouring a caterpillar, 
leave its vitals unattacked. 
Let us now suppose that the flesh of a trichinised pig is 
served up at table, and is eaten by some unfortunate human 
being. The first step is that the calcareous cyst or capsule 
is dissolved by the acid juices of the stomach, and its inmate 
is set at liberty to repeat the career of its parents. But un- 
fortunately its presence in man is always attended with great 
pain and serious danger, and in the majority of cases with 
