146 JOURNAL OF ENTOMOLOGY AND ZOOLOGY 



thick outer body wall, but surrounded by a mass of connective 

 tissue as well. Tlie nerve which it receives is extremely minute 

 when compared to the nerve which goes to the rhinophores, for 

 instance, and there is no organized retina. 



The rhinophores are situated well forward and somewhat 

 at the sides of the head. They consist of a stout central stalk 

 divided transversely into twelve prominent leaves. The length 

 of the central stalk is about 0.6 mm. in the contracted condition. 

 AVhen retracted, the rliinojihores are completely withdrawn into 

 a little cavity in the integument, the upjier surface of the rhi- 

 nojihore being at a level with the oi)ening of the cavity. In 

 section it may l)e seen that the lamellae are covered by an epi- 

 thelium of tall, slender cells with small, darkly-staining nuclei 

 in the basal portion. These cells appear to bear short cilia, but 

 not nearly such prominent ones as those in some other places, 

 as the foot. A very large nerve enters the stalk of the rhino- 

 phore and gives five branches to the lamellae. Muscle fibres 

 run up the sides of the stalk and these also send a few fibres 

 to the lamellae. The rhinophores are by far the most highly 

 developed sense organs of L. cockerelU. 



The tentacles and the suli-pallial ridge receive large nerves 

 which end close to their upjier surfaces, which are somewhat 

 lamellated and bear a ciliated epithelium. 



The Eepeoductive System. The hermaphroditic gland is a 

 racemose gland extending over the uiiper surface of the liver, 

 below and between the branches of the uephridia. It reaches 

 down on both sides below the level of the paiiillae and extends 

 well over the caudal and cephalic ends of the liver. The sper- 

 matozoa develop in large follicles, each surrounded by several 

 smaller ovarian follicles which open into it. The spermatic 

 follicles open into small ducts which come together to form the 

 large duct of the hermai)hroditic gland. In all but one of the 

 specimens examined, both ova and spermatozoa were develop- 

 ing. In that one the female organs were dormant and the ova 

 had only just begtm to develop. The ovarian follicles usually 

 contain several ova in various stages of growth as well as small 

 cells with a darker-staining protoplasm that were wedged in 



