ICO THE MEDUSAE. 



The difference between the two series of specimens, Pacific and West 

 Indian, consisting merely of a slight divergence in such a variable character 

 as the number of rudimentary tentacular knobs, seems to me too slight to 

 warrant separating them specifically. To determine whether it even indi- 

 cates the existence of two distinct geographic races of the one species 

 requires an examination of additional large specimens, particularly from the 

 Pacific. 



P. comata is clearly distinguished from the other members of the genus 

 by the presence of lateral cirri at the bases of the tentacles, a very 

 constant and reliable character ; and by the small number of otocysts. 

 In the large size of the latter, however, it resembles P. virens. 



Eirene Eschscholtz, 1829. 



Haeckel, 1879. 



Eucopidae with well-developed gelatinous peduncle ; with numerous 

 otocysts and tentacles ; gonads restricted to the subumbrella. 



Haeckel ('79) enumerated only four species of this genus : E.pellucida Will, 

 E. viridula Lamark, E. gibbosa McCrady, and E. coerulea L. Agassiz. To these 

 must be added the Eutiiua pyramidalis of L. Agassiz, which has since been 

 redescribed by Mayer (:00 b ) under the name Phortis pyramidalis. All these 

 are Atlantic forms. Since Haeckel wrote, five new species have been 

 described : — E. lactea Mayer (: 00 b ), from the West Indies, E. kambara Agassiz 

 and Mayer ('99), from the Fiji Islands, and E. danduensis Bigelow 

 (: 04), E. ceylonensis Browne (:05 b ), and E. palkensis Browne (:05 b ), from 

 the Indian Ocean. It is, however, doubtful whether all of these are truly 

 distinct; indeed the status even of the two longest known species, E. /></- 

 lucida and /,'. viridula, is not yet satisfactorily determined. The probability 

 is that they are specifically identical, but as Mediterranean and Atlantic 

 specimens are known to have a wide range of variation in size, tentacle 

 Dumber, and form of the peduncle (Haeckel, '79; Maas, '93), it is possible 

 that the W. viridula — JE. pellucida group may in reality comprise two or 

 more geographic races. This species, or group, is apparently the most 

 widely distributed of the genus; but though it has been recorded twice 

 from the Indian Ocean (Chun, '96; Goette, .'86), there seems to be no 

 record of its occurrence on the western side of the Atlantic. E. danduensis 

 and /.' palkensis Bhow many features in common; in both there are com- 

 paratively few tentacles, with a large number of rudimentary tentacular 



