SPECIAL ANATOMY. 211 
and the pedal disk, at the side of the pulmonary orifice. 
The salivary glands are arborescent, or fasciculated in 
appearance. The ducts are short and delicate. The 
lobuli of the liver are looser, or more separated, than in 
the pi-eceding genera. 
Helix. The buccal body has the same appearance, 
generally, as in the slugs. The retractor muscle is 
much stronger, and has its origin in common with the 
retractor of the foot and tentaculae, from the columella of 
the shell ; at its insertion it forms a semicircle around the 
posterior inferior part of the buccal body. The pouch of 
the lingual lamina is always a prominent object. In H. 
cellaria and H. concava, the buccal body is proportionately 
nearly twice the length of that of the other species. The 
dental plate varies in some degree in different species : in 
IT. ligera, H. intertexta, &c. it is smooth anteriorly, and 
in the middle projects downwards into a large, conical 
toothlet ; in H. albolabris, H. tridentata, &c. the ante- 
rior surface presents a number of curved ridges, each of 
which projects inferiorly as a sort of toothlet. 
The oesophagus is generally long and narrow. In 
some species it is unusually long and contracted, as in 
H. concava, H. cellaria, H. hirsuta, H. perspectiva, etc. ; 
in others it is long, and dilated in the middle, as in H. 
auriculata ; in many it is capacious, and gradually passes 
into the stomach, as in H. exoleta, etc. 
The stomach is usually cjlindroid, and more or less 
sacculated. The posterior cul-de-sac is always present. 
