CESTODA 73 



conclusion that had been drawn by practical helminthologists 

 from various sources of information. In regard to the number of 

 proglottides proper to a sexually mature tapeworm, the circum- 

 stance that Perroncito's calculation was made without the head 

 and a portion of the neck of the worm being present shows that 

 it cannot be relied on absolutely ; nevertheless, as far as it goes, 

 it tends to confirm what Leuckart had long previously stated. 

 I have possessed myself of upwards of thirty perfect beef 

 tapeworms expelled from my patients, and in some of the 

 specimens it was noticed that the segmentation-rings in the 

 region of the neck were far more crowded together than they 

 were in others. I also possess a perfect Tcenia mediocanellata, 

 removed post mortem. Though the rate of growth may be the 

 same from day to day, yet experience has shown that the number 

 of proglottides actually cast off varies exceedingly. Kiichen- 

 meister's estimate of the average number agrees in the main 

 with what we have ourselves observed (five to twenty daily) ; 

 and here again Perroncito's investigations serve to verify the 

 general correctness of our previous determinations. 



To return to Pellizzari' s researches, one of the most important 

 questions is that which relates to the prevalence of tapeworm. 

 In this connection he first brings forward some very interesting 

 and instructive data that had been previously communicated to 

 the Medico -Physical Academy of Florence by Professor Marchi. 

 On the occasion referred to Marchi had stated that, out of thirty- 

 five Tsenise which he had examined, only one belonged to the 

 species known as Tcenia solium ; all the other thirty-four being 

 of the unarmed type, or Tcenia mediocanellata. Reflecting on 

 this striking fact, and also on the circumstance that he had in vain 

 begged his colleagues to send him specimens of Tcenia solium, 

 Marchi seems to have missed the very palpable explanation of 

 this otherwise strange phenomenon. " How does it happen," 

 exclaimed Marchi, " that, notwithstanding the occurrence of 

 13,000 kilogrammes of the flesh of measled hogs in the public 

 butcheries, I have seen but one specimen of Tcenia solium, 

 whilst thirty-four cannot have originated from the pig ?" " The 

 wherefore is obvious enough," replies Pellizzari, " because our 

 hygienic regulations demand that the flesh of the hogs be raised 

 to a temperature of 60 Cent. (140 Fahr.) " and he then himself 

 immediately proceeds to ask another question, namely, as to how 

 it happens that the Tcenia solium is so frequently seen in other 

 places. To his own question Pellizzari responds by remarking 



