maxilhi. 



384 TAGR SKOOsr.RRr; 



1 have obtained c(intirniation of this idfntificatioii by a re-examination of the typespecimen 

 of this species of Bhady's (it is kept in the / o o 1 o g i c a 1 AT u s c u ni at C o p e n h a g e n). 

 Unfortunately only the shell is left of this important specimen; all the other organs are missing. 

 As is shown by the description of the sub-genus given by me above, several mistakes were found 

 in Brady's description and figures. Contrary to what one would be inclined to expect from 

 Brady's statements, the type specimen exhibits a marked relationship to the species described 

 by me below. 

 .Xiinihrrof .yyecips. h\ addition to .1/. (C.) javus there are certainly two other species belonging to this sub- 



genus, namely Cypridina Bairdi G. S. Brady (1865, p. 387; pi. 62, fig. 7 and 1897, p. 88; pi. 16, 

 figs. 22 and 23) and Cjipridina asymmetrica (i. W. Muli.ki; (1906 b, p. 14; pi. 6, figs. 1—12). 

 Of these two species, whicii are certainly very closely related to each other, the former is very 

 little known; the latter, on the other hand, is one of the better known representatives of this 

 sub-familv. Roth of them confirm the correctness of the nmv description of the sub-genus 

 I have given above. 



On account of the incompleteness of the descriptions it is impossible to decide whether 

 iiiiv more of tlie species hitherto described are to be included in this group. 

 FiinctLon (ij ihc With n\gard to tlie function of the maxilla in tliis sub-genus it may be pointed out heio 



that the [)alp of tliis limb is certainly to be considered as an important organ of locomotion, while 

 the endites — as is usual in this sub-family — are masticatory organs. This double function 

 is rendered possible by the fact that the palp and the part from which the endites issue are 

 cajiable of free motion independently of each other. 



All the forms of this sub-gen\is so far known come from the western part of th(^ P a c i f i c. 

 ('J'he locality of the type specimen is, however, unknown.) 

 Type species. Type species: M. (C.) javm. (!. S. BliADV, 1902 a. 



M. (Cypridinodes) acuminata n. sp. 



Description: — Male: — 



Shell: — Length, 5,.5 mm. Length : height, about 1,5 : 1; this applies to the left 

 valve, the right one is somewhat lower. Length : breadth, about 2:1. Seen fro m t h e 

 s i d e (fig. 1), it has its greatest height at abotit the middle and the posterior part of the shell 

 is not, at least not perceptibly, larger than the anterior part. The dorsal and the ventral margins 

 are arched rather boldly and almost uniformly and evenly, tlie ventral margin is, however, 

 somewhat irregular, as it is somewhat pouting anteriorly; both join the anterior and the posterior 

 margins without coiners. The posterior part of the shell foiins, at about half the height of tlie 

 shell, a rectangular, pointed corner. The rostrum has anteriorly a strongly projecting but 

 bi'oadlv round(Hl cornei'; its ventral corner is narrowly rounded and strongly marked because 

 tlie ventral pait of the anterior margin of the rostrum curves inwards rather decidedly. The 

 narrow and rather deep rostral incisur is characterized by having its posterior margin defined 

 from tlie ventral margin of the shell by a rather strongly marked corner. S e e n f r o m a b o v e 



Dlflrihiilioii. 



