EIRENE MEDUSIFERA. 161 



knobs; in both the peduncle is long and in both the gonads are linear. 

 The only important differences between the two are the facts that E. pal- 

 kcnsis has a much shorter manubrium than E. dauduensis, and that Browne 

 was unable to find any lateral cirri at the bases of the tentacles in the 

 former, while I have recorded such structures for the latter; but neither of 

 these differences is as important as it might seem at the outset, for the first 

 character is subject to great variation owing to contraction ; the absence 

 of cirri in E. palkensis may perhaps be explained by the fact that the 

 bell margins of all the specimens were much damaged (Browne, :05 b ). I 

 therefore believe that in all probability the two are identical. 



Browne was no doubt justified in separating E. ceylonensis from E. 

 palkcnsis {dauduensis) in spite of the close general resemblance between 

 the two, on the grounds that the former has a very much larger number 

 of tentacles (100), but neither cirri nor tentacular knobs. It appears to 

 represent a good species. Both of these Indo-Pacific species (or three if 

 E. palkcnsis be recognized as separated from E. dauduensis) are sufficiently 

 well distinguished by anatomical characters from any of the Atlantic mem- 

 bers of the genus. The status of E. kambara Agassiz and Mayer is less 

 easily settled. From their figure ('99, pi. 8, fig. 29) it is evident that the 

 specimen was immature; although they mention gonads, the figure shows 

 none ; and the fact that the margin bears neither cirri nor knobs suggests 

 that it may be the young of E. ceylonensis. If this is the case, however, the 

 peduncle must grow very considerably in length during the later stages 

 of development, for it is figured by them as very short in E. kambara. 



The present collection contains two species referable to Eirene; one, 

 represented by only a single specimen, from the open ocean, is indistin- 

 guishable from E. viridula. The other represented by a considerable 

 series, is apparently new. 



Eirene medusifera, sp. nov. 



Plate 37, Figs. 1-8. 



Acapulco Harbor; surface ; 23 specimens, 2.5-8 mm. in diameter. Type 



7 mm. in diameter. 



The specimens are all in excellent condition. 



The bell is of moderate height, the jelly rather thin. The peduncle 



(PI. 37, fig. 6) is conical, and hangs about to the opening of the bell. 



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