ox DIPLOZOON NIPPOXICUM, N. SP. 181 



erstehend." Poirier^ ^ describes the nervous fibres oi' D slnnnm clavatum 

 as filling up tlie entire cavity of the meshes. But an examination of 

 the nerves in a fi-esh state shews very distinctly the exceedingly fine 

 fibrils. They do not seem to be so regularly arranged as Pintner 

 supposes, and are not at all large enough to fill up the entire cavities 

 of the meshes. Without doubting the correctness of Poirier's obser- 

 vation, I am convinced that in Diplozoon the nerves consist of a 

 frame- work of connective tissue, in the meshes of which i"un tlie true 

 nervous fibrils. I liave not observed any of the nervous cells describ- 

 ed by Larig and others in the ner\es. This set me to a careful 

 searcli after ganglion cells, as these were not also to be found in the 

 brain, where in other species they make such a conspicuous figure 

 especially in the peripheral portion. But I have ncjt been able to 

 find out any to which 1 could decidedly pinnt as nervous cells {Vide 

 supra p. 171). 



VII. The Reproductive System. 



We now C(jîne to the consideration of the most complicated 

 system, the reproductive organs. Of these the female portion consists 

 of the vitelline body, the ovary, the oviduct, and rhe uterus, with a 

 "connecting canal" the natiu'e of which is not at all clearly known. 

 The male portion consists of the testis with a single vas deferens. 

 I shall beo-in with the latter. 



The Male Organs — The testis is a nearly globrdar or ovoid body 

 situated about midway between the point of crossing of the two in- 

 dividuals and the posterior niargiji of the body, and is composed of 

 many lobes. Each hjbe is separated from its neighbour and from 



^) Poirier — Coatribution h l'histoire naturelle des Tréiuatodes. Arch. d. zool. expérimen- 

 tale 2e. Série. T. III. 1885. p. 603. 



