76 JOHNS HOPKINS UNIVERSITY MORPHOLOGICAL MONOGRAPHS. 
Another peculiar phenomenon presents itself in these cells. The 
distal part of each cell becomes separated off from its body by what 
appears to be the formation of a transverse cell-wall (Fig. 31, c-d). I 
have found the ends of these cells quite separated off in some series. 
The formation of the walls seems to begin as a thickening at the sides 
of the cells, and a section through this region, transverse to the cells, 
would appear like Fig. 30. The dots in the centers of the polygonal 
areas of this figure are the centrad continuations of the cilia to be 
described below. As already remarked in describing the endoderm 
of the ampulla, I believe we here have another place of origin of 
the ‘floating cells.” The secretion just described moves into the 
distal parts of the cells prior to their separation (Fig. 31). In some 
series I could see these secretion bodies much more numerous within 
the distal ends of the cells than in Fig. 31. 
As will be seen in Fig. 31, each of the endoderm cells of the 
tentacles has a flagellum that extends into the lumen of the tentacle. 
Each flagellum has a thickening just within its cell, which may be 
regarded as a basal body. From this basal body, again, a small fiber 
extends centrad into each cell. It does not appear that the flagella 
are thrown off with the distal parts of the cells; at all events, I never 
found them connected with any of the floating cells except in a few 
doubtful instances. 
What I have said for the endoderm of the tentacle of Charybdea 
apples equally to Tripedala. 
Claus, in his figure of a transverse section of a tentacle of C. 
marsupialis shows the endoderm as cubical. I cannot explain why 
there should be such a difference between the endoderm of the 
tentacles of C. marsupialis and that of the tentacles of C. Xaymacana 
and Tripedalia cystophora. Claus does not describe the endoderm in 
detail. 
The endoderm cells of the pedalia of both Charybdea and 
Tripedalia are cubical and possess flagella, basal bodies, and centrad 
continuations, quite like those I have described for the endoderm cells 
of the ampulla. The double nature of the basal bodies and the centrad 
continuations is, however, not so evident. A secretion I did not find. 
Histologically, therefore, the endothelium of the pedalia corresponds 
rather with that of the ampulla, and that of the tentacles with that 
of the peduncle of the clubs. 
