DIPHYOPSIINAE. 245 



or the absence of wing-like expansions of the ridges. To summarize Lens and 

 Van Riemsdijk's account, D. gegenhauri is the smallest (65-82 mm.), it has 

 four serrate ridges at the apex, the lateral teeth are small, and there are no 

 "wings." D. indica is 9-11 mm. long; the dorsal ridge is not serrate; there 

 are five ridges at the apex; lateral teeth are very large; "wings" are present. 

 D. malayana is 9-10 mm. long; the dorsal ridge is slightlj' serrate in its distal 

 part; the lateral teeth are large; there are four ridges at the apex, but no " wings." 

 The present excellent series allows me to test these characters; and the condi- 

 tion in fifty specimens of varying size, tabulated below (p. 252), shows that all 

 of them are subject to so much individual variation as to be cjuite worthless for 

 specific diagnosis. The .series shows every gradation between the three species, 

 which must, therefore, be united in one. Lens and Van Riemsdijk have already 

 noted that Doromasia picloides closely resembles their Diphyes gegenhauri, 

 and though they class the latter among the Monophyidae, they admit that 

 future study may prove it to be a Diphyid. That it is a Diphyid is shown bj' a 

 specimen in our collection which, though agreeing with D. pictoides in form and 

 in the presence of a single terminal group of appendages, is slightly larger and 

 has an easily identified bud for an inferior nectophore (Plate 12, fig. 1). Lens 

 and Van Riemsdijk have already noted the close resemblance between their 

 several species, and the Doromasia bojani of Chun. The position of the latter 

 (known from only one specimen lacking any trace of stem or appendages) 

 among the Monophyidae rests merely on the supposition that it is the poly- 

 gastric generation of Ersaea bojani. But the resemblance between Chun's 

 ('92) figure and several of our specimens with "wings" which have inferior 

 nectophores still attached, is too close to allow any conclusion other than 

 that they are identical with the gegenbauri-indica-malayana group. On the 

 grounds of priority bojani must be chosen for the compound species resulting 

 from the union of D. gegenbauri, D. indica, D. malayana, Doromasia bojani, 

 and D. pictoides. This name, it is true, has long been used for an Eudoxid; 

 but the latter probably belongs either to the present species, or to another 

 family (p. 265), and in either case the name bojani can be used for the Diphyes. 

 D. bojani, as Lens and Van Riemsdijk point out, is closely allied to two 

 Atlantic species, D. steenstrupii Gegenbaur and D. serrata Chun. The former, 

 it is true, has been classed b> Schneider ('98) as a synonym of D. appendiculata 

 ( = bipartita) but an examination of Gegenbaur's account convinces me that 

 its true relationship is as here noted. Unfortunately, Chun's description (with- 

 out figures), of sfrra/a, where he says that the outline of the hydroecium differs 



