294 DISCOVERY REPORTS 



Cosmetirella davisi belongs to the antarctic and subantarctic seas ; it is recorded from : 

 Falkland Islands (Browne, 1902), South Georgia (Kramp, 1932; and Thiel, 1938), 

 Kerguelen Island (VanhofFen, 1912 «), Gauss Station at Kaiser Wilhelm II Land 

 (Vanhoffen, 1912 a), and South Victoria Land (Browne, 1910). 



This species is named after John Davis, an English navigator who discovered the 

 Falkland Islands in 1592. 



Family "EUCOPIDAE" 



The family name "Eucopidae" is provisionally retained in the present paper, but 

 a revision is needed, for the genus Eucope, from which the name is derived, has proved 

 to be obsolete (see p. 296). 



Genus Obelia Peron and Lesueur (1809) 



Generic characters. " Eucopidae "with numerous solid tentacles ; with eight adradial 

 statocysts situated on the inner side of the basal bulbs of eight of the tentacles ; no 

 marginal cirri ; a sack-like gonad on each of the four radial canals. Velum rudimentary. 



Obelia multicia Browne (Plate XVI, figs. 6-8). 

 Obelia multicia Browne, 1902, p. 281. 



Specific characters. Adult: Umbrella flat, disk-shaped. Stomach small, with a 

 quadrangular base. Gonads globular or ellipsoid, about midway between the stomach 

 and the margin of the umbrella. Tentacles short, about 100-120, with a large, heart- 

 shaped basal bulb. Marginal statocysts small, adradial. Size: up to 3-5 mm. in diameter. 



Vallentin's first collection contains sixteen specimens of this species, 1-3 mm. in 

 diameter, taken in Stanley Harbour between 23 January and 4 February 1899. The 

 second collection contains numerous specimens, from early stages, 0-35 mm. in diameter, 

 to adults, 3-5 mm. wide, collected in Stanley Harbour 12 December 1901 to 17 January 

 1902. In the third collection there are some few specimens, taken at Port Egremont 

 28 October 1909 (one specimen) and at Roy Cove 23 November 1909 (eight specimens, 

 0-5-2-5 mm. wide). 



As a rule it is impossible to distinguish the medusae of the various species of Obelia 

 from each other. There is no doubt, however, that the specimens here dealt with all 

 belong to one species, which is characterized by its large, heart-shaped tentacular bulbs. 

 In the fully extended condition the basal bulbs may be globular as in other species of 

 the genus, but in the vast majority of the specimens examined they are distinctly heart- 

 shaped, being broader in their distal part than at the base (Plate XVI, fig. 7). Even in 

 the youngest specimens the basal bulbs have this characteristic appearance. 



The prolongation or root of the tentacle in the substance of the umbrella beyond the 

 ring canal is short and has the appearance of a large cell, which is occasionally divided 

 by a transverse septum. 



In several specimens the mouth is fully expanded and is either oval or circular in 



