78 COLLINGE : ANATOMY OF SLUGS. 



ANADENUS, Heyn. 

 A. sechuenensis, n. sp. I'l. iv, figs, i, 2, 6, 7, pi. v, figs. S— 13. 



Animal olive brown with a faint, dark, mid-dorsal band and darker 

 lateral bands. Mantle ovoid, large, marked with a postero-median 

 diamond-shaped, light space, with dark bordering, a few indistinct 

 black spots laterally. Respiratory orifice slightly behind the middle 

 of the mantle. Generative orifice below and behind the right lower 

 tentacle. Rugae small, irregular in outline, in groups divided by deep 

 black sulci. Peripodial groove small but distinct. Foot-fringe same 

 colour as the body, lineoles almost black. Foot-sole divided into lateral 

 and median planes, the former being dark ashy-grey or blackish, the 

 latter olive brown. 



Length (in alcohol) 74 mm.; length of mantle 34.5 mm. ; breadth 

 of foot-sole 23.5 mm. 



Shell a thin, flat, calcareous plate with no periostracum. Length 

 12 mm.; breadth 5.5 mm. 



Hah. — Sung pan, N. \V. Sechuen, China. 



Anatomy. 



Digestive System. — This agrees in the main with the description 

 and figure of A. altivayus, Theob., given by Pilsbry (14), differing 

 however in a few points. The buccal cavity leads into a short oesoph- 

 agus, at the point of junction of these two the salivary glands open 

 by their ducts on the dorsal surface. Both of the glands are folded 

 upon themselves and, in the specimen dissected, were partly ventral to 

 the buccal cavity and oesophagus. There is a wide crop which nar- 

 rows posteriorly and opens into an ill-defined stomach, which is 

 divided into two parts, the hepatic ducts entermg posteriorly between 

 the two, here terminates the first loop of the digestive tract; the second 

 loop passes forwards beneath the crop, anteriorly appearing above it, 

 and bending backwards forms the third loop, this is continued back- 

 wards beyond the stomach and making a single revolution, returns 

 forwards beneath the stomach as the fourth loop, and passing across 

 the middle of the crop as the rectum it terminates at the anus on 

 the right side {PI. iv, fig. 6). 



The Jaw. — I have to thank the Rev. Professor H. M. Gwatkin, 

 M.A., of Cambridge, for very kindly examining this and the radula. 

 It corresponds exactly with the description given by Pilsbry (14) of 

 that in ^4. altivagus, Theob. 



The Radula (^^tIt^ = 14S03) differs from that in A. altivagus 

 in the smaller size of the cusps of the central teeth. 



