42 



THE AMERICAN MONTHLY 



MarchJ 



for they have been found in its tis- 

 sues only in isolated cases (Leuckart, 

 Fiedler). 



These parasites are not equally 

 distributed over the muscular system, 

 but, on the contrary, seem to have 

 their favorite places of abode. They 

 appear to have a predilection for the 

 muscles of the anterior part of the 

 body. Among these, those of the 

 tongue, larynx, pharynx, eye, and 

 masticatory muscles are especially 

 favored. The muscles of the body 

 are more frequented than those of the 

 extremities. Very few are found in the 



Fig. 10.- 



-Normal encapsuled Trichina'. 

 (Leuckart.) 



inferior portion of the tail of any ani- 

 mal. In the extremities, the parasites 

 are found to be more abundant v/here 

 the muscle-fibres begin to Ipse them- 

 selves in their tendinous extension, 

 than in the body of the muscle. The 

 following interesting and valuable 

 statistics, with reference to the dis- 

 persion of the trichinae over the 

 organism, are taken from the Mitt- 

 heilungen aus der Thici-drzlichen 

 Praxis im preussischen Staate, 1877- 

 78, p. 99. 



Eighty preparations from hog No.i 

 I gave the following results : — 

 a from the pillars of diaphragm, 12 trichinae 

 b from the muscles of diaphragm, 4 trichinae 

 c from the laryngeal muscles, . 1 trichina 

 d from the intercostals, 

 e from muscles of the tongue, 

 / from muscles of the neck, > no trichinae 

 g from muscles of the eyes 

 and humerus. 



Leuckart estimates that in some of 

 the cases which have come to his ob- 

 servation, a single gram (fifteen 

 grains) of flesh lodged from twelve 

 hundred to fifteen hundred trichinae. 

 Assuming the muscles of a man to 

 weigh forty pounds, the number of 

 these parasites infesting a human 

 organism, at such a ratio, would sum 

 up some thirty millions. In Zen- 

 ker's case, — to be noticed later, — Fied- 

 ler calculated that the woman lodged 

 some ninety-four millions ; and Cob- 

 bold assumes that a hundred millions 

 may sometimes infest one organism 

 at the same time. 



In seventy specimens weighing one 

 gram. Ranch found three hundred 

 and fifty trichinae, at that rate one 

 pound would contain a hundred and 

 seventy-five thousand, and, if the 

 flesh of a hog weighs a hundred 

 pounds, it would, at such a percent- 

 age, contain seventeen million five 

 hundred thousand trichinae. In many 

 cases, however, the parasites, are 

 much less frequently met with ; and 

 one has to search through many mi- 

 croscopic preparations before meet- 

 ing any, and then only isolated ex- 

 amples. 



The calcification of the capsule 

 begins about the fifth month after 

 the invasion of the muscles. In the 

 ordinary pork which is generally of- 

 fered for inspection, this is not the 

 case, sufficient time not having 

 elapsed for the calcifying process to 

 take place, and the parasites, or, 

 more correctly speaking, the capsules, 

 are not to be seen with the naked eye, 

 a magnifying power of fifteen to twen- 

 ty diameters being sufficient to their 

 recognition by the practised ob- 

 server ; but for exact inspection a 



II 



