MEDUSA 133 



A Comparison between the Medus.e of Ceylon and those of the 



Maldives. 



It is somewhat hazardous to draw a comparison between the medusoid fauna of 

 Ceylon and that of the Maldives. About that of Ceylon I feel that we at present 

 know but little, in fact, we have just made a beginning in our observations. We 

 know, perhaps, a little more about the medusae of the Maldives, which have recently 

 been visited by two expeditions the hrst under the leadership of Mr. Stanley 

 Cardiner, and the second, which soon followed the first, under the guidance of 

 Professor Alexander Agassiz. 



Leaving out the oceanic medusa 1 , which have usually a wide geographical range, 

 and limiting the comparison to the Anthomedusa? and Leptoniedusas, Mr. Gardiner's 

 collection contained 5 genera and 5 species (3 of which were new species). Professor 

 A'i.vssiz's collection contained 10 genera (1 new genus) and 11 species (6 of which 

 were new species and 3 were not named). With the possible exception of one of the 

 iiEquoriicUe, the genera and species were quite distinct in the two collections. Taking 

 the two collections, without any limitations, there is a well-marked difference between 

 them, which is quite as great as if they had come from localities a thousand miles 

 apart. It is difficult to assign a correct reason for such a difference, but probably a 

 different season of the year and the localities visited had much to do with it. 



The two Maldive collections contain altogether 14 genera and 15 species of 

 Anthomedusse and Leptomedusa?. The Ceylon collection contains 12 genera and 

 14 species (10 of which are regarded as new species). A comparison between the 

 Maldive and Ceylon collections shows that 6 genera [Dipurena?, Proboscidactyla, 

 Irene, Trenopsis, Mesonema and yEquorea) are common to both, but only 2 species 

 (Irenopsis hexanemalis and Mesonema pensile ; the former also occurs at Zanzibar 

 and the latter in the Red Sea), I think that these figures show clearly that the 

 medusoid fauna of Ceylon is quite distinct from that of the Maldives. 



HYDROMEDUSJL 



Order : ANTHOMEDUSSE. 



Family: SAKSIID^E, Forbes, 1848. 



Dipurena, McCrady, 1858. 



Dipurena, sp. ? Plate II., figs. 1 and 2. 



Description. Umbrella about as high as broad. Manubrium extending beyond 

 the margin of the umbrella. Mouth circular. Gonads arranged in several large 



