448 MisceUaneous. 



On the Termination of the Nerves in the Electrical Apparatus of the 

 Torpedo. By M. C. Rotjget. 



The author says that on examining the nervous lamina of the 

 electrical disks of the torpedo on the ventral surface, which receives 

 the ultimate ramifications of the pale fibres, the preparations being 

 unaltered by any reagents, there is constantly to be observed a net- 

 work formed by the division of the^last branches of the pale fibres, 

 which are ramified like stag's horns. The apparent terminations 

 in knobs or free extremities, which may show themselves here and 

 there in all preparations, are seen in enlarged photographs to be 

 manifestly connected with the network by processes which elude 

 direct observation. The solutions of continuity of the meshes which 

 are observed in preparatio'.js treated in the fresh state with nitrate 

 of silver or chloride of gold are not constant, and are produced by 

 the injurious or irregular action of the reagent. 



Seen on the ventral surface of the nervous lamina, the filaments 

 which bound the meshes are smooth and have their borders regular ; 

 but when th.e completely isolated nervous lamina is examined on its 

 dorsal surface, these filaments present an irregular surface, bristling 

 with processes, which, in some cases, are seen to be arranged in 

 regular series upon the sides of the filaments, so as to resemble the 

 barbs of a feather. These fibrils are of the same substance as the 

 filaments of the network from which they directly proceed ; they 

 are elementary nervous fibrils, parallel to each other, and placed 

 peipendicular to the plane of the nervous lamina, from the ventral 

 towards the dorsal surface ; and at this end they unite to form an 

 arcade, and constitute a last and truly terminal network, the meshes 

 and filaments of which are scarcely one fourth of the dimensions of 

 those of the network of the ventral surface. The two nervous net- 

 works together and the processes which unite them form a reticu- 

 lated spongy layer, with meshes diminishing in size from the ventral 

 to the dorsal surface, in which the nervous elements anastomose in 

 arcades, and in which not a single free extremity is to be met with. 

 — Comptes Rendus, August 27, 1877, p. 485. 



Prof. HaeclceVs Group of the Physamarice. 



Mr. W. Saville Kent, F.L.S., has remitted us a paper of considera- 

 ble length, bearing for its title " Remarks upon Professor Haeckel's 

 Group of the Physamariae'" and which, there not being space 

 at disposal this raonth, will appear in a forthcoming number. 

 These " Physamariae," including, according to Haeckel's views, Mr. 

 Carter's Squanndlna scopida, Mr. Saville Kent concludes to be amjily 

 demonstrated by Prof. Haeckel's own drawings and descriptions to 

 be true sponges, but at the same time the simplest representatives 

 of their class yet discovered. In this simplicity they are shown to 

 closely correspond with a single spherical " ciliated chamber " or 

 " ampuUaceous sac " of certain of the more complex types. 



