172 



ON ANEITEA GRAEFFEI AND IT a ALLIES. 



insertion of the oesophagus. They are united by long slender com- 

 missures to each other, and to the main ganglionic mass. 

 Embracing the oesophagus midway between the buccal mass and the 

 stomach are the supracesophageal above and the subcesophgeal below. 

 Besides several minor nerves to the lips, the supracesophageal 

 ganglia give rise to the large optic nerves, the right one of which 

 goes under and over the genitalia on its way to the tentacle. The 

 suboesophageal ganglia are an agglomerated mass of five nerve 

 centres, on two of which are placed the auditory sacs containing the 

 otolithes. Nerves are supplied by the suboesophageal ganglia to the 

 various viscera. 



The genitalia, with the exception of the penis sac which lies 

 on the left side, occupy the right anterior quarter of the visceral 

 cavity. The position of the organs resembles that of its near ally 

 Athoracophorus, and differs from most pulmonates whose testicle is 

 enfolded in the liver. The whole system is distinguished by the 

 length and slenderness of all its parts. The testicle lies on the 

 stomach in the centre of the animal having the rectum on 

 its left side. It is a subrotund body, divided into two 

 lobes which are again partially subdivided into follicular 

 masses. The epididymis leading therefrom enlarges from 

 its threadlike origin immediately after leaving the gland and 

 assumes a flattened, much contorted appearance. The accessory 

 gland which, .Jut again diminishing, it enters, is of a yellow 

 colour, and is seen on opening the body from above Next to it 

 lies the ovary, a smooth white horn shaped body. The male- 

 system is continued in the prostate, a wrinked yellow duct 

 wrapped round the oviduct which it much resembles. From the 

 lower end of the prostate originates the vas deferens. This 

 winds down to the common genital chamber and then up to 

 the posterior end of the penis sac. About 18 mm. from its junc- 

 tion with the latter is fastened the retractor muscle of the penis. 

 Dr. Bergh describes and figures a series of small thorns which 

 stud the penis, The genital bladder is oval, of a purplish tint T 

 and is situated high up on the vagina upon which it is almost 

 sessile.- In Keferstein's figure it is sketched larger than accords 



