MEDUSA. 9 
The Antarctic species of Koellikeria has fewer tentacles, with smaller compound 
basal bulbs, than are present in the species found in warm water and there are no 
ocelli. The absence of ocelli is not a characteristic feature of the Antarctic Meduse, as 
Eleutheria possesses them. 
The species of Desmonema found within the Antarctic region has about seven very 
thick tentacles in each group, but the species found in the Magellanic region has as 
many as sixty slender tentacles in each group. 
The new genus, Cosmetirella, of the Mitrocomide is characterised by possessing no 
ocelli and no cirri. Their absence shows characters more primitive than are found in 
the other genera of the family. 
Bathymetrical Distribution.—The occurrence of Periphylla at the surface on 
the Antarctic coast shakes my faith in the term “deep-sea” Meduse, as it is commonly 
understood. The origin of the name is due to Prof. Haeckel, and is based upon 
certain Medusz collected by the ‘ Challenger.’ * It is necessary to remember that the 
nets used by the ‘Challenger’ were all open nets. The self-closing net is a later 
invention, and has not been very extensively used even by recent expeditions. The 
deep-sea Medusze have been regarded as permanent inhabitants of the lowest zones of 
the oceans, living in very cold water and in darkness, and carefully avoiding sunlight 
and warm water. 
Mr. Bigelow (1909) discusses very fully the bathymetrical range of Meduse, and 
his conclusions are partly based upon the results obtained by the ‘ Albatross’ in her 
cruise (1904-5) over the Eastern Tropical Pacific. Both Periphylla and Atolla were 
taken by the ‘ Albatross’ within 300 fms. of the surface (one specimen of Periphylla 
was captured within 200 fms. of the surface). Within the area worked over by the 
‘ Albatross’ the temperature of the sea at the surface was between 65° F. and 85° F. ; 
at 200 fms. between 48°5° F. and 56°7° F.; at 300 fms. between 42°7° F. and 482° F. ; 
and at 400 fms. 41°9° F. and 42°5° F. Bigelow states that ‘not a single species 
was taken in hauls below 300 fms. which was not taken in other hauls between 
300 fms. and the surface; although the majority of the genera of Medusz as 
yet known to belong to the intermediate fauna were taken during the expedition, 
and several of them in considerable abundance.” With regard to the term 
“intermediate” fauna, Bigelow prefers to adopt “intermediate” in preference to 
“deep-sea” (“Tiefsee”), as he term is ambiguous from its common application to 
abyssal bottom animals. 
There is good evidence that some of the deep-sea Medusz extend down to about 
1,000 fms., but we do not yet know the depth which they usually frequent. Many 
more hauls with self-closing nets will have to be taken before we can find that out. 
* Cf. The Athenceewm for July 16th, 1881, where the writer (who may safely be supposed, from internal 
evidence, to have been Professor Moseley) said: ‘‘In reality there is no proof that any of the corals came 
from a greater depth than thirty fathoms. The dredge ranged whilst down from thirty fathoms, or one 
fathom, or ten fathoms to greater depths; but there is no proof that it did not pick up the corals at the least 
depth encountered.”—Ep. 
