E. W. BERGER ON THE CUBOMEDUSZ. 7 
One cannot help but remark how analogous is the behavior of 
meduse, in respect to light and darkness, to the behavior of many 
of the higher animals,—and medusze are among the most lowly 
organized of the animal creation. 
Were one to conclude from the behavior of Charybdea in hght 
and darkness in the laboratory, that it remained on or near the 
bottom in the daytime but became more active near or at the 
surface evenings, nights and early mornings, one would probably not 
be far from the truth. Dr. Conant, while towing near the bottom 
with a weighted net, in water four to five feet (1.2-1.5 m.) deep not far 
from shore and deeper farther out, found Charybdea in abundance 
mornings and afternoons, but very few in the evening. In the 
evening some few were usually taken in the surface tow. (See Intro- 
duction, Occurrence and Activity.) 
Again, who knows but that Charybdea is active during the day, 
on the bottom where it was dredged (the light there would only be 
moderate), and quiet at night. This supposition would seem to be 
true, at least, for those forms of Cubomeduse that live in deep 
water. We can hardly suppose that they should regularly rise to 
the surface from great depths and become active. This much we do 
know that bright light inhibits Charybdea’s activities, while it 
probably would not be active in perfect darkness. 
I do not know just what interpretation to put upon Conant’s 
finding Charybdea at Port Henderson at the surface during the 
early part of the forenoon, before the sea-breeze roughened the water 
(‘“Cubomeduse” p. 7). This fact hardly fits in with my conclusions 
above. Perhaps Charybdea’s habits vary with its habitat. 
Finally, while I find no experimental evidence in Conant’s notes 
about what parts of Charybdea are sensitive to light, yet it would 
seem preposterous, from histological evidence and from Romanes’ 
results on Sarsia, to doubt that the eyes of the marginal bodies are 
the seat of this stimulation. 
Dr. Conant further experimented by cutting off certain organs 
and parts from the Cubomedusan bell. These excisions consisted 
chiefly in cutting out the concretions of the sensory clubs, cutting off 
the whole club, eliminating a part or whole of the margin and the 
velarium, cutting the bell into sectors, excising the stomach and 
parts connected with it, and other parts. 
