MUSEUM OF COMPARATIVE ZOOLOGY. 2at 
been taken in the Atlantic or in the Mediterranean, with the exception of the 
problematical P. sicula, Haeck., from Messina. 
In his original description Prof. Verrill suggests that Callinema is allied ‘to 
Heccedecomma ambiguum, Brandt, of the North Pacific, but finds that the 
Eastport species differs from the Pacific in the shape and character of the ten- 
tacles, the marginal lobes, and ovaries, and that the figures of the Pacific form 
have much more complicated mouth-folds. I agree with Professor Verrill in 
his conclusions in regard to the differences between the two medusz, and find 
his medusa specifically different, not only from the published figures of the 
Pacific Phacellophora, but also from specimens themselves, some of which were 
collected on my recent visit to the Pacific coast. It is also believed to be 
generically different from Hecceedecomma. 
Haeckel* suggests that Callinema is a new species of Phacellophora. There 
are close likenesses between Callinema and Phacellophora, and also differ- 
ences which seem great enough to give the name Callinema a generic worth. 
Haeckel, however, regards these differences as specific only, and regards Calli- 
nema as a new species of Phacellophora. In the same genus he places three 
other species, camtschatica, Brandt, ambigua, Brandt, and sicula, Haeckel. I con- 
sider, as stated above, that there is a generic difference between Callinema and 
the first two species. Of the third species, from Messina, there are no special 
descriptions, and no figures of the medusa as a whole, and we are wholly in the 
dark in regard to the structure of the mouth parts. What is known from the 
notices by the Hertwigs t— the figures are of a quadrant of the bell and an en- 
larged sense body — would lead me to suppose that his medusa is very close to 
Callinema. It would seem to be a species of Callinema allied to C. ornata. 
Until we know more of its general anatomy, we must remain in doubt whether 
it is more closely allied to Phacellophora or Callinema, I can heartily agree 
with Haeckel that an exact study of the structure of the medusa considered by 
Hertwig is very desirable. The author believes that histological researches 
lose some of their value if not preceded by an accurate specific identification 
or specific description of the animal studied, if it is different from known 
species. 
* Das System der Medusen. Acraspeden, p. 648. 
+ Nervensystem und Sinnesorganen der Medusen, pp. 113, 114, Taf. IX. Fig. 
15, Taf. X. Fig. 16. 
CAMBRIDGE, October, 1887. 
