GASTEROPODA OF THE UNITED STATES. 17 



The srniill intestine comes off from the stomach at a 

 very acute r.ngle, and into tlic latter two hepatic ducts 

 empty. It is pretty uniformly cylindi-icjil, and forms, as 

 in slugs, a single convolution or a sigmoid curve, among 

 the lobes of tlie liver, and penetrates to the pulmonary 

 cavity at its right posterior angle, ^flie rcctmn, in all 

 the testaceous genera, corresponds in length to the pul- 

 monary cavity, the right side of wliich it occupies to the 

 pulmonary orifice, at the outer border of which it ter- 

 minates by the anal aperture. It is cylindrical, usually 

 wider than the small intestine, and is frequently some- 

 what sacculated. U[)on the outer side of the rectiun, 

 running its whole length, is a band of muscular fi])res, 

 the object of which is, apparently, the retraction of the 

 collar, the shortening of the rectum, and the expulsion 

 of its contents. 



The salivary glands are generally elongated, oval, with 

 lobed edges. They are usually uinted together and 

 situated on the oesophagus, or commencement of the sto- 

 mach. When the oesophagus is narrow they surround 

 it ; when dilated, they occupy one-half or two-thirds of 

 its surface. The salivary ducts are long and large. 



The liver is four lobed, three of which lobes are ante- 

 rior or inferior, and the fourth posterior or superior. The 

 fourth lobe, conjoined with the testicle, forms the very 

 summit of the turbinated mass. The ducts from tlie 

 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 intes- 

 tine. 



