366 GEOGRAPHICAL DISTRIBUTION. 



ard, Nedrodroma reticulata Bigelow, Abyla haeckeli Lens and Van Riemsdijk, 

 Diphtjabyla hubrechti Lens and Van Riemsdijk, Diphyes contorta Lens and Van 

 Riemsdijk, Diphyes spiralis Bigelow, and Diphyopsis chamissonis Huxley. Some 

 of these may be found in the Atlantic in the future, a suggestion rendered prob- 

 able by my own discovery of Abyla leuckartii (p. 321) and of Diphyopsis mitra 

 (p. 261) in the West Indies. 



The list includes twenty-seven Physophorae, twelve recorded from both 

 oceans, besides the genus Forskalia (p. 270), seven so far recorded only from the 

 Atlantic, eight from the Indo-Pacific. Of the Atlantic species four, Ayahna 

 clausi, Erenna richardi, Anthophysa formosa, and Angelopsis globosa are repre- 

 sented by extremely close allies in the Indo-Pacific. These are Agalma haeckeli, 

 Erenna bedoti, Anthophysa rosea, and Angelopsis dilata. One Atlantic species, 

 Stephanomia car a, is doubtful; at this moment it is impossible to determine 

 whether or not it is distinct from S. bijuga (p. 283). If so, it is a boreal form. 

 And it is likewise impossible to state from Brandt's ('35) brief description, whether 

 the Pacific Apolemia is the same as, or different from the Atlantic representative 

 of the genus (p. 348). The Indian Apolemia, however, {"Dicymba diphyopsis" 

 Haeckel, '88b) is apparently indistinguishable from the Atlantic A. uvaria. This 

 leaves only Anthemodes ordinata, Stephalia corona, Rhodalia miranda as Physo- 

 nectae peculiar to the Atlantic ; and it is possible that the latter belongs to the Paci- 

 fic also (Brooks and Conklin, '91). The following exclusively Pacific species are 

 well grounded : — Stephanomia amphitridis Peron and Lesueur, Dromalia alexandri 

 Bigelow, and Archangelopsis typica Lens and Van Riemsdijk. But the last two, 

 like Rhodalia, belong to a group so little known that no inferences as to distri- 

 bution can yet be drawn from their few records. Another Stephanomia, S. 

 cupulifera Lens and Van Riemsdijk was described as new from the "Siboga" 

 collection; but its distinctive character was so trivial (p. 284) that its standing 

 is doubtful. Discolabe quadrigata and Rhodophysa corona likewise require 

 further stud3^ There are eleven recognizable Rhizophysaliae, of which four 

 are known from both oceans, three from the Atlantic only, and four from the 

 Indo-Pacific. Each region has its own peculiar species of Physalia, and to the 

 Indo-Pacific belongs the interesting genus Epibulia, while Salacia is so far known 

 only from the Atlantic. The other Rhizophysalids peculiar to one or the other 

 region only belong to the Bathyphysinae, a subfamily whose members have been 

 taken so seldom that their records can not be used yet as a basis for geographic 

 discussion. 



Among Chondrophorae the genus Porpema is common to both oceans: but 



