GERM CELLS OF COELENTERATES 389 
leptostyla that the entoderm was the place where the egg cells 
originated; Goette (’07), in his very extensive paper on the germ 
cells of hydromedusae, showed conclusively that in many forms 
the germ cells came from the entoderm, others from the ectoderm 
and still others indifferently from one or the other. He says, for 
example, referring to Podocoryne carnea, that egg cells were 
found in the entoderm of the bud, in the ectoderm, and from all 
developmental stuffs of the medusa bud (p. 81). Again: ‘For 
me, therefore, no doubt exists that the germ cells of Clava multi- 
cornis proceed only from transformed half-entoderm cells’ And 
later (p. 414) he says: ‘‘ However, after it has gnce been established 
that the germ cells of Hydropolyps originate sometimes in the 
entoderm, sometimes in the ectoderm . . .. .. it is natur- 
ally of little fundamental concern which mode is current for the 
separate species.”’ Smallwood (’09) in Hydractinia finds the 
egg cells arising in the entoderm. C. W. Hargitt (’11) in a general 
paper on coelenterate ontogeny calls attention to the work of 
Goette and of others and of the stand which Weismann has taken 
in regard to these facts, and reference should be made to these 
papers for a fuller discussion. 
It may not be amiss, however, again to call attention to the fact 
that the work of Goette, the present paper and others furnish 
exactly the evidence demanded by Weismann himself as a proof 
of the origin of germ cells from the entoderm. Weismann says 
(p. 237) ‘“‘If the egg cells were of entodermal origin, they must 
proceed by cross division of ordinary entodermal cells, with the 
result that the distal half bordering the enteric cavity remain 
epithelial cells, the basal half becoming only germ cells.” The 
work of Goette shows this, and the present paper in figure 3 
represents that just this thing has occurred, the basal half of the 
cell becoming a germ cell, the remainder continuing as an ordinary 
epithelial cell. Figure 4 is another drawing of a similar stage; 
in this the nucleus of the distal half of the original epithelial cell 
is present in another section. As already stated, not all egg cells 
of C. flexuosa are so formed, some coming from a transformed 
entire entoderm cell (fig. 2) but in all cases from the entoderm. 
