Miscellaneous. 463 



not found in these animals when very young. In his first experi- 

 ment, M. Van Beneden used two newly- born puppies, and brought 

 them up under exactly the same conditions, except that to one of 

 thein a certain number of Cysticerci were administered in his food, 

 whilst these worms were carefully kept from the second. The 

 Cysticerci were administered at three different times, viz. on the 12th 

 and 23rd of March, and on the 21st April. These dogs were killed 

 and opened on the 25th April, when the animal which had eaten no 

 Cysticerci was quite free from the TcBnia serrata, although the 

 lower part of its intestines contained a single worm of a different 

 species, the Tcenia cucumerina. The other dog, to which the Cys- 

 ticerci had been administered, contained three bundles of worms, 

 which were regarded as the Tcenia serrata by M. Van Beneden and 

 the majority of the other observers. The bundle which was furthest 

 from the stomach, and which was considered as proceeding from the 

 first administration of Cysticerci, was composed of Tsenias which had 

 nearly arrived at the adult state ; the other two packets were less 

 advanced, that nearest the stomach being the smallest, and regarded 

 as produced from the Cysticerci last administered. The same re- 

 sults were obtained from another similar experiment; but as this 

 had been going on for a much longer period (the first injection of 

 Cysticerci having taken place on the 18th December), the Tsenias 

 situated at the greatest distance from the stomach were not only 

 larger than in the previous experiment, but had the generative organs 

 well developed. In all these cases the number of Tsenias found in 

 the intestines was less than that of the Cysticerci sw^allowed ; thus,, 

 the first dog had received thirty- two, and the second seventy of the 

 Cystic worms ; but the former contained only seventeen, and the 

 latter twenty-five Tsenias. 



M. Van Beneden informed M. Milne-Edwards that he has repeated 

 these experiments no less than thirteen times, and always with equally 

 decisive results. Similar experiments have also been performed by 

 Kiichenmeister, Von Siebold^, and Leuckart, and always with the 

 same success. 



The objections raised by M. Valenciennes to the deduction drawn 

 by M. Van Beneden and other authors from the observation of the 

 above facts, namely that the Cysticercus pisiformis of the rabbit is 

 the larval form of the Tcenia serrata of the dog, repose principally 

 upon the question of the specific identity of the parasite produced by 

 the administration of the Cysticerci to the last-mentioned animal 

 with the Tcenia serrata, a worm which is so common, that, M. Valen- 

 ciennes states, it may almost be predicted with certainty, that on 

 opening a dog of four months old and upwards, this parasite will be 

 met with. Previous experiments had proved to M. Valenciennes' 

 tliat the administration of the Cysticercus pisiformis to dogs " gives 

 rise to a flattened riband, composed of numerous narrow articulations, 

 and presenting at the first glance exactly the appearance of a Toenioid 



* Annals, N. S., No. 60, Dec. 1S52, p. 431. 



