THE MIGRATIONS OF ENTOZOA. 175 



counted about 100 lively scolices. Wlien killed, forty-five 

 days afterwards, it afforded also only a negative result. 



But if we admit that some serious doubts still require to 

 be dissipated, Avith respect to the transmigration of the Ccenu- 

 rus cerebri of the sheep to the intestine of the dog, we are 

 infinitely more decided with respect to the peregrination of 

 the ova of the Tcenia of the carnivora to the brain of the 

 ruminant. 



Our experiments were made upon two lambs, to each of 

 which we administered ten segments of Tania serrata, all of 

 which contained a number of perfectly matured ova, in which 

 might be distinguished the embryo with its hooks. The 

 sheep, which had been carefully selected as in perfect health, 

 never presented the slightest symptom of " staggers." Ex- 

 perimenters say that the symptoms of this disease are ordi- 

 narily manifested from the fifteenth to the twentieth day; 

 but in order to avoid any precipitancy, we kept our animals 

 for four months. Though still in perfect health, they were 

 then killed, in order to ascertain whether the brain contained 

 any vestige of Canurus ; but on the autopsy that organ was 

 found perfectly sound. Consequently, in these cases there had 

 been no transportation of the progeny of the Tcenia of the 

 dog to the brain of the sheep. 



Considering, therefore, the doubts which arise when we 

 regard attentively the assertions of experimenters, and those 

 also which arise upon a rational examination of the proofs, 

 and lastly, the results of our experiments, we do not hesitate 

 to assert that the offspring of the Tcenia of the dog never 

 reaches the brain of the sheep. 



But although we deny thus strongly the transmission of 

 the entozoon of the dog to the brain of the sheep, we should 

 not be astonished — without admitting that this is the normal 

 course — to find that it may be possible that the Ccsnuri of the 

 latter animal were individual Tcenias, which have undergone 

 an arrest of development, owing to the situation in which 

 they have been born, and which aborted Tcenias, being placed 

 by the experimenter in a more propitious place, there elon- 

 gate themselves, and attain a larger size than they present in 

 the brain. This opinion has been already sustained. 



We are continuing our experiments, and shall, without 

 doubt, be able to arrive at a solution of this interesting 

 problem."^ 



* In the ' Comptes rendus' for June 2nd, 1862, is a letter from Prof. Van 

 Beneden, in answer to some of the statements in the observations of MM. 

 Poucliet and Yerrier, and in the number for June IGtli is a rejoinder from 

 tliose authors, maintaining their former propositions. Of these papers an 

 abstract will be given in our next. [Ed. M. J.] 



