62 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



and the fourth posterior or superior. The fourth lobe, conjoined with 

 the testicle, forms the very summit of tlie turbinated mass. The ducts 

 from the anterior lobes converge to form a single trunk, which, with 

 that from the posterior lobe, open into the junction, or angle, of the 

 cul-de-sac of the stomach with the intestine. 



BiNNEYA. The oesophagus is very short ; the stomach very wide, 

 short. 



BuLiMULUS. The digestive apparatus in B. dealhatus and B. imdti- 

 lineatus resembles that of Polygyra aiiriculata ; the oesophagus is long, 

 narrow, and dilated in the middle; the stomach is cylindroid, and 

 more or less sacculated. 



Stenogyra. The digestive system is like the last. 



LiGUUS. The stomach of Liguus fasciatiis resembles that of Limax 

 flavus^ being large and capacious anteriorly, cylindrical and sacculated 

 posteriorly. The rectum is capacious and sacculated. 



OiiTHALicus. The digestive system of undatus is as in Liguus. It 

 does not essentially differ from that of the genera of disintegrated 

 Helix. 



Pupa. A characteristic of this genus is the very great proportionate 

 length of the viscera, corresponding to the numerous whorls of the 

 shell. The retractor muscle of the buccal mass is long and strong. 

 The oesophagus is very long and narrow. The stomach is very long, 

 and even forms a fold npon itself. The rectum is very long and saccu- 

 lated ; the muscle on its outer side is well developed. 



SucciNEA. A characteristic of this genus, the reverse of Pupa^ is the 

 great breadth and shortness of the viscera. The dental plate, or jaw, 

 has an upper quadrangular piece, superadded to the ordinary crescen- 

 tic plate. The stomach resembles that of Limax Jiavus. Its mucous 

 membrane presents several longitudinal rugse. The small intestine 

 does not undergo the same relative diminution with the other viscera. 

 The rectum is very short, and, from the transverse position of the pul- 

 monary cavity, it is placed along the right of the breadth, instead of 

 the length of the latter, as usual. The salivary glands are situated one 

 on each side of the commencement of the stomach ; their ducts, just 

 before opening into the buccal body, become dilated. 



Macrocyclis. The buccal mass, as stated above, is twice the size of 

 that of the other genera. 



Glandina. The oral orifice is triangular, and bounded by three 

 papillated lips, one upper and two lateral. The buccal body is a very 



