ON THE ANASPIDACEA, LIVING AND FOSSIL. 533 
universally present. The median pieces (x and F) correspond 
to the urocardiac ossicle and median tooth of the Decapoda. 
The piece (z) is present in most Malacostraca, but the posterior 
piece (F) possibly points to Decapodan affinities. The great 
length of the lateral pyloric pieces (A and B) in Anaspides 
resembles the condition of the Euphausiide and not that of the 
TrExtT-Fic. 40. 
+0. 
Stomach from ventral surface. 
Peracarida, in which these pieces are short. Again, in the 
Peracarida there is a complicated median ventral ridge in the 
pyloric division, which in the Euphansiide is simpler and 
appears to be absent in the Anaspides, while the elongated 
ventral ridge (#) inthe cardiac division of Anas pides recalls 
closely that of the Euphausiide. Wemay therefore conclude 
that in those points in which the gastric mill is not merely Mala- 
