General Morphology. 



and vas deferens {vd) of one side, the latter two organs being bilateral, but the ganglion median 

 and unpaired. The testes (t) are small tubes lying in the mesentery, while the ovaries (ov) 

 occupy the main bulk of the visceral mass. Such are the main outlines of the anatomy of 



Text fig. 2. 

 Ideal longitudinal section passing a little to one side of middle line. 



Peltogaster, and this essential organization is followed out with various complications in the other 

 genera of Rhizocephala. 



The proximity of the ganglion to the mantle opening, and the position of the oviducts 

 between the ganglion and the vasa deferentia. give us the clue to the orientation of the body 

 relatively to normal Cirripedes. In Text fig. 3 B is represented a diagrammatic longitudinal 



-2* 



^■ovxL 



Text fig. 3 A. 



Text fig. 3B. 



section through a typical Cirripede, and here the essential relations of brain [gn\ oviduct (ovd) and 

 vas deferens {vd) are shown to be the same as those in Peltogaster represented in Text fig. 3 A ; 

 the peculiarly anterior position of the oviducts in normal Cirripedes being reproduced in Pelto- 

 gaster. The relations of the mantle in our typical Cirripede and in Peltogaster are seen to differ 



Zool. Station zu Neapel, Fauna und Flora, Golf von Neapel. Rnizocephala. 



