Some Notes on Alcippe lampas (Hanc.). 195 
It sometimes reaches almost to the surface of the disk. In Fig. 15 
we look down ventrad into this first portion with its many folds, 
subdivisions and pits. The second portion is the middle portion 
extending as a wide cylinder down the dorsal side of the body 
parallel with the disk we may say. It is simple, giving off small 
lobes and pits only here and there. It is difficult here to determine 
the body wall proper. The stomach bulges into the disk and this 
whole region is actually imbedded in the disk. The third portion 
extends from the second almost at right angles. It begins in the 
first post-discal segment, having here about the form of a hollow 
hemisphere. In its wall we have the slips of the third protrusor 
and second retractor muscles as described above. Between the 
muscle bands the stomach has rows of pits, evaginations which 
extend almost to the very surface of the body. 
Between the first and second post-discal segments the stomach 
is always distinctly constricted. Beyond this it extends into the 
second and third post-discal segments as a wide sac gradually 
tapering and finally sending two small lobes way into segments 4 
and 5. The ventral wall of this third portion of the stomach extends 
so far as to leave only a narrow shelf-like partition between it and 
the extension of the first portion. This shelf is seen in cross section 
in Fig. 15, in sagittal section in Fig. 16. It is filled by muscles, 
especially the strong third protrusor which goes to the last segments 
lies here. The ventral wall of the stomach-sac in post-discal seg- 
ments 2 and 3 is smooth, but the dorsal wall has again many 
evaginations and pit-like depressions which extend almost to the 
surface of the body wall. 
This very peculiar arrangement of the digestive tract simplifies | 
the circulation greatly, at least inside the body proper. The stomach 
is practically everywhere and sends its projections right among the 
muscles and organs. The pouch-like evagination mentioned above 
which extends out of the body into the disk and is always present 
seems to be for the benefit of the strong muscles which attach the 
body to the disk. 
Another peculiarity which excited my greatest interest when I 
studied my serial sections, is the differentiation of certain cells here 
and there among the epithelial cells. These large cells which we 
may justly call liver-cells are pretty evenly distributed all over the 
epithelium of the stomach, a little more crowded perhaps in the 
pits, so that digestion can go on everywhere. But since BERNDT 
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