Notes on Trichinae. 87 



blood. On examination the muscles were found to be literally 

 crowded with trichinje. All muscular surfaces were distinctly 

 granulated to the unaided eye, and under the microscope the 

 parasites were foCind so closely crowded as practically to 

 occupy the entire place. In some fields of the microscope 

 there was not even a shred of a muscle visible — nothing but 

 cysts bound together by a very scanty development of connec- 

 tive tissue. A large proportion of the C3-sts contained two or 

 more worms. Three or four in one cyst was no uncommon 

 occurrence, five w'ere occasionally seen in the same sac, and 

 m at least one instance observed a single cyst contained six 

 trichince. By moistening the fresh tissue with normal salt 

 solution and pressing a small piece of it somewhat vigorously 

 between two slides, many of the cysts were ruptured and the 

 worms set free. In the salt solution they could be kept active 

 for an indefinite period, and the observer might have at any 

 time a dozen or more of the free worms writhing and squirm- 

 ing in the field of his instrument. 



The rat in question showed symptoms of being greatly en- 

 feebled by its enormous burden of parasites: and it, with its 

 fellows, exhibited signs of inordinate thirst. Water was more 

 attractive than any other bait, and it was the desire for water 

 that led to the capture of the specimen here described. This 

 individual would certainly soon have fallen a victim to the 

 appetite of its fellow rodents, and every morsel of its flesh 

 would have been competent to inoculate thoroughly a large 

 section of the rauscine community. Such an individual tends 

 to dispel all mystery regarding the manner in which rats, cats 

 and swine obtain these dangerous parasites. 



Rats abound in all close hog pens and are doubtless the 

 chief means whereby trichinae are perpetuated and transmitted 

 to swine. The total annihilation of rats is probably out of the 

 question, but I doubt not if they were exterminated the dan- 

 gers to humanity arising from trichinae would be immensely 

 reduced if not altogether stamped out. So long as rats per- 

 sist we may secure practical safety by selecting for food only 



