ON THE ANASPIDACEA, LIVING AND FOSSIL. a31 
minal segment, which also belongs to the mid-gut, but 
immediately below it the character of the epithelium entirely 
changes, and a chitinous lining, marking the proctodzal 
invagination, covers the internal surface of the intestine. 
The anus opens ventrally on the telson. 
We will now describe these various portions in more 
detail. 
The stomach may be divided into an anterior cardiac and 
a posterior pyloric portion. The division between them is 
marked dorsally by the first diverticulum of the alimentary 
TEXT-FIG. 38. 
Anaspides tasmanizw. Stomach removed from body and viewed 
laterally. For lettering see text. 
canal, and ventrally by the entrance of the liver cxca, so 
that the cardiac portion is stomodzum while the pyloric is 
endodermal, although chitinous pieces of ectodermal origin 
are projected into the pyloric division. 
The cardiac portion of the stomach is furnished with a 
pair of lateral elevations carrying sete. Hach lateral eleva- 
tion is in the form of an incomplete circle, the sete being 
present in two main pieces of the ridge, viz. c and D in text- 
fios. 38, 39, 40. There is also present a median setose pro- 
minence (r), and a more posteriorly placed tooth (r) which 
projects into the pyloric cavity. In the median ventral line 
there is a prominent pad (H) (text-fig. 40) which projects 
