WOODWARD : ANATOMY OF NATALINA CAFFEA. 275 



ParypJtanta a median gland with two ducts, while the other forms, 

 as far as is known, possess two distinct glands and ducts. 



The oesophagus in both specimens which I have examined was 

 a contracted thick-wallod tube. It is probably highly distensible. 



Pace, in describing the anatomy of N. Trimeni, speaks of the 

 oesophagus being displaced to the right side of the buccal mass owing 

 to the enlargement of the latter; now in both my specimens, if it 

 were displaced at all, it was to the left, and this displacement appears 

 to be due rather to the enlarged hermaphrodite duct than to the 

 buccal mass, unless one regards the latter as causing a displacement 

 of the former, which consequently pushes the oesophagus to the left. 



The rest of the alimentary canal (Fig. 1) calls for no special 

 comment, and closely resembles that of Helix. 



The pulmonary chamber is large, and its outer wall highly vascular 

 (Fig. 1), the heart in its pericardium being situated in the left 

 posterior corner of this chamber ; a large kidney is on the right of 

 the pericardium and opens by a short ureter (m.) into the pulmonary 

 chamber close to its posterior limit, there being no long recurved 

 ureter as in Helix. 



The arterial system was injected in a fresh specimen, but showed 

 no marked differences from that of Helix ; only, the buccal mass being 

 very large, it conse(^uently receives much larger branches than the 

 corresponding organ in the common snail. 



'The pedal gla7id, as noted by all, attains enormous development 

 in the Agnatha, and especially in Natalina, where it is generally 

 doubled once or twice on itself. In N. Caffra it opens as usual 

 between the head and foot, just below the mouth, and then extends 

 back in the body cavity as a thick- walled, slightly convoluted tube 

 situated immediately below the great retractor muscle, the course of 

 which it follows for a short distance towards the visceral dome, when 

 it suddenly bends shai-ply on itself and runs forwards and downwards, 

 only to bend back again into the substance of the foot, where it ends 

 blindly. 



Reproductive organs. — The genitalia of Natalina have been described 

 by Pilsbry and Pace from imperfect specimens. In both examples of 

 N. Caffra which I have examined the genital organs were enormously 

 developed, especially the albumen gland and the hermaphrodite duct. 

 The ovotestis is situated in the right lobe of the liver, and consists of 

 numerous ca?cal tubes communicating with a closely coiled duct 

 {Ji.d., Fig. 1); this enters a huge albumen gland divided into a 

 glandular and a coiled portion, the commencement of the herma- 

 phrodite duct, which becomes a large, much convoluted tube 

 divided into a well-marked opaque, brownish, prostatic portion (i?r.) 

 and a translucent, white, oviducal duct (o«;.). The former com- 

 municates with a slightly coiled vas deferens (v.d.), which opens into 

 the end of the penis sac (p); this sac is bent on itself, the 

 retractor muscle (r.p.) being attached at the angle. The portion 

 between the vas deferens and the angle, contains the protrusible penis : 

 the remaining portion communicates with the genital cloaca. After 

 giving off the vas deferens the rest of the hermaphrodite duct passes 



