E. W. BERGER ON THE CUBOMEDUS^. 71 



show the association of the nuclear phenomenon with the secretion. 

 I have failed to find any descriptions in the literature of nuclei to 

 which I could refer my observations. 



The endothelium of the ampulla is flagellated (Figs. 7, 17, 27). 

 It will be seen that there are two slender flagella to a cell. Each 

 pair of flagella has a pair of basal bodies that are longer than thick, 

 and which are continued as a thin fiber towards the nucleus of the 

 cell. That these centrad continuations of the basal bodies extend to 

 or past the nucleus I could not determine. Sometimes the basal 

 bodies with the centrad continuations are pushed quite to one side 

 of the cell (Fig. 27), while in other cells they are applied quite to the 

 distal surface (Figs. 7, 17, 27). Fig. 17, and the part of Fig. 7 that 

 shows these points, are taken just through the tips of the cells. The 

 darker lines within the polygonal areas are the intracellular basal 

 bodies with their centrad continuations, while the thinner lines are 

 the flagella, and are supposed to lie in the plane just below the 

 plane of the figure. In those instances in which the centrad con- 

 tinuations are applied to the distal surface of the cells they could 

 occasionally be seen to bend centrad (Fig. 27b). While these cilia with 

 their basal bodies and centrad continuations are usually separate, as 

 shown in the figures, yet they are at times applied quite closely to 

 each other so that the double nature of the basal bodies and their 

 centrad continuations is not evident. When the intracellular con- 

 tinuations of the cilia become pushed to one side or applied to the 

 distal surface of the cells, I believe this to be due to the turgor of 

 the cells consequent upon the deposition of large masses of secretion 

 within them. But I must add that this explanation is not alto- 

 gether satisfactory, since in the endoderm cells of the pedalia of 

 both Charybdea and Tripedalia I found like conditions with no evi- 

 dence of a secreting function. (See below, under tentacles.) No one, 

 to my knowledge, has described the flagellation in detail, although 

 both Glaus and Schewiakoff state that the endoderm is ciliated. 



The "floating cells" in the stomach pockets and in the ampulla, 

 described by Conant, I believe are in part derived from the endo- 

 thelial cells of the ampulla. That a portion of them may arise from 

 the ovary, as Conant explains, I do not doubt ; I have, further, found a 

 mass of floating cells in a small Charybdea quite as Conant describes 

 for Tripedalia (his Fig. 71). In this Charybdea, however, I could find 

 no traces of any ovary. Conant speaks of larger and smaller floating 



