284 NOTES AND MEMORANDA. 



witli a thicker caudal region. lu the genus Ascai-is there are two 

 series of hirval forms, one with and one without a boring denticle ; of 

 the former series the larvte of A. capsularia, A. eperlani, and A. com- 

 munis are of a relatively enormous size. The paper is illustrated by 

 three plates. 



Excretory Apparatus of Solenophorus megalocephalus. — M. 

 J. Poirier * having some Solenophora, which had only remained a 

 short time in alcohol, injected their excretory apparatus, and on 

 examining the result saw that it did not agree with what had been 

 hitherto published. 



Instead of two longitudinal vessels on each side of the segments 

 (the mode of communication between them not having been hitherto 

 noticed), M. Poirier found, as in Duthiersia, six such vessels. The 

 two internal ones alone communicate with each other by transverse 

 canals, situated, as in all the Cestoids, at the commencement of 

 each segment. These vessels, which (with the exception of the in- 

 ternal ones) have in the segments no direct communication with 

 each other, in the scolex form a network which unites them. The 

 external vessel, when it reaches the scolex, buries itself more deeply, 

 passing under the two others and going along the groove which 

 separates the two bothridia, towards the extremity of the scolex ; 

 there it divides into two branches, which ramify in each bothri- 

 dium. The median vessel, of a smaller calibre than that of the 

 two others, passes above the external vessel, and about the middle of 

 the length of the scolex bifurcates into two branches which unite to 

 the network formed by the divided branches of the external vessel. 



The internal vessel bifurcates immediately after its entrance into 

 the head, and forms a network of very large meshes which is joined 

 to the network of smaller meshes arising from the external vessel. 

 These three pairs of vessels therefore only form one system. 



Besides the above vessels, which are of a considerable size, we 

 find on the surface of the body, a second system of fine vessels, which 

 M. Blanchard j^ointed out some time ago in the Tsenise as a circulatory 

 apparatus, and whose existence Gegenbauer denies altogether in his 

 ' Comparative Anatomy.' These vessels, which are very tine, form on 

 the surface of the segments and of the scolex a network of rectangular 

 meshes, much closer in the Solenophora than in the Taeniae, in which 

 the longitudinal vessels of this network are few in number, as 

 M. Blanchard has shown in Taenia solium, and as M. Poirier has 

 proved in T, crassicollis of the cat. This network is only inter- 

 rupted ai'ound the genital orifices : according to M. Blanchard it is 

 completely isolated, but in reality communicates with the preceding 

 system. Indeed, in the posterior part of each segment, the external 

 vessel of the first system sends out a branch as far as the edge of the 

 segment, and there produces ramifications which go into the external 

 longitudinal vessels of the second system. The other vessels of the 

 first system have no communication with these fine peripheral vessels ; 

 but, as they reunite in the scolex with the external vessel, it follows 



* ' Comptes Kendus,' Ixxxvii. (1878)1013. 



