CESTTJM VENEEIS. 123 



economy. M. Delle Chiaje* states that, upon the inner surface of each 

 of the eight ciliated ribs, there is discoverable a longitudinal oviduct, to 

 both sides of which are appended bunches of ovules, an observation 

 the accuracy of which is doubted by Milne-Edwards, who finds, indeed, 

 on each side of the ciliated bands a multitude of little racemose bunches, 

 of a rose colour, having the appearance of ovaria, but to whom it seemed 

 that these bunches were contained in the substance of the walls of the 

 body, and were simply dilatations of the lining membranes of the sub- 

 ciliary vascular canals, which, instead of communicating with a common 

 oviduct, opened into the vessels themselves. 



(322.) From the researches of Willf, it would appear that these 

 Acalephs are hermaphrodite, the generative apparatus consisting of 

 elongated utricles, the testes being situated on one side and the ovaria 

 on the other. Both sets of organs are described as having a nodulated 

 appearance, and from the nodulated part of each passes off an excretory 

 duct, which runs towards the mouth ; but the terminal openings of 

 these canals have not been made out. In Professor Grant's description of 

 Cydippe pileus, of which a figure is given above (fig. 58, l), the ovaries 

 are said to consist of two lengthened clusters of small spherical gemmules 

 of a lively crimson-red colour, extending along the sides of the alimen- 

 tary canal. It is evident, therefore, that further knowledge relative to 

 this department of the economy of the Beroes is still a desideratum in 

 science. 



(323.) The Cesium Veneris (fig. 59) is nearly allied to the Beroe in 

 the arrangement of its nutritive apparatus, notwithstanding the differ- 



Fig. 59. 



ence of form observable in these Ciliograde Medusae. In Cesium, the 

 digestive cavity, which is exceedingly short in comparison with the 



* Mem. sulla steria e anatomia degli Animali senza Vertebre, torn. iv. p. 12. 

 t Horre tergest. p. 38. tab. 1. figs. 22, 23. 



