ANTIOPA, 



that the optic nerve (^) is of considerable length. The nerve (j), supplying the reproductive 

 organs, comes off from a delicate collar, which has its two ends inserted apparently into the 

 branchial ganglia at their junction with the pedial, just where the visceral ganglion is 

 situated in Doris. This arrangement is the same as in Eolis. Ten or eleven pairs of nerves 

 have been ascertained to belong to the supra-cesophageal ganglia. 



The infra-cesophageal ganglia are placed much further apart than usual, having the 

 median commissure very wide ; the cords, too, that unite them to the cerebroid ganglia are 

 very long. The gastro-cesophageal (m, m,) are joined to the buccal ganglia {I, I,) by shorty 

 nerves, giving the former a pedunculated character : they send three pairs of nerves to the 

 oesophagus, the two principal of which supply that tube, one passing down it. 



Portions of the sympathetic nervous system have been distinctly traced on the generative 

 organs,* and will in all probability be found on the other viscera. 



The eye seems to be as well developed as in any of the nudibranchs ; and from the high 

 development of the dorsal tentacles, and the crescentric enlargement of their base, olfaction 

 would appear to be extensively enjoyed. The auditory organ was not examined by us, but 

 M. Blanchard places it in the usual situation immediately behind the optic nerve. 



The reproductive apparatus fills the greater portion of the body; and is prpvided with a 

 very large intromittent organ (fig. 9 b), which receives one end of a short, stout, tubular 

 testis (c) ; the other end of the testis tapers a little before it joins the oviduct. The ovary, 

 which fills much of the cavity of the body, is composed of two lobulated masses, one (fig. 1 o) 

 a little in advance of the other (p). The oviduct (fig. 9 d) is at first very slender ; but as soon 

 as it reaches the mucus-gland, it greatly and suddenly increases in diameter (e), and as it 

 approaches, in a tortuous course, the anterior border of that organ, it as rapidly diminishes 

 almost to its original caliber. It then shortly after doubles upon itself (/), and is connected 

 with the testis ; afterwards the oviduct is again a little dilated (y), as it draws near to the 

 spermatheca (/£), which is rather small. The duct (/) of the spermatheca is short and 

 constricted ; but, after its junction with the oviduct, is enlarged, and sends a short branch [m) 

 down into the mucus-gland. This duct, which must now be considered the vagina (n), passes 

 on in a straight line to the external opening between the male and the female outlets. In this 

 animal there is no accessory spermatheca ; but the two dilated portions of the oviduct appear 

 amply sufficient to make up for the deficiency. Perhaps the enlargement of the oviduct at 

 its junction with the duct of the spermatheca may more particularly subserve the function of a 

 second receptacle. The mucus-gland (h, i), which is pyriform and somewhat compressed, 

 resembles the same organ in Doris more than that of Eolis. 



* Traces of the sympathetic nervous system have been observed on the reproductive organs and on 

 the stomach of Eolis, since the description of that genus was drawn up. 



