studies oti marine Ostracods 171 



medes and Astern fe. It appears to me that there is a support for this assumption 



in the following facts: 



That the endite on the coxale of the mandible was originally bifurcated in the Cy- 

 fridini formes seems to be supported by the fact that bifurcation is found not only in the 

 sub-family Philomedinae and the Asteropids but also in Cyfridininae and Sarsiellidae. 

 Moreover, in the sub-family Cypridininue the bifurcation of this process is best developed 

 in that genus which we have rather good reasons to assume as the most primitive, viz. 

 Crossophorus, cf. below, p. 182. In most species of the family Sarsiellidae this process seems 

 to be absent, but when it does occur it is deeply bifurcated, at least according to G. S. 

 Brady and A. M. Norman, 1896, PI. LX, fig. 10. This endite is not developed, so far as 

 is known, in Rutidermatidae. — I must not refrain, however, from stating that there are 

 facts that might be considered to point in the opposite direction; cf. below p. 182. — The 

 supposition that the basale of the mandible in Cypridiniformes originally had an endite 

 is supported by the fact that an endite on this joint occurs in Halocypriformes, Polycopi- 

 formes and Asteropidae, and traces of one in Phuomedinae, Cypridininae, Sarsiellidae and 

 Rutidermatidae; in the Cyridinenes the traces are best developed in the genus 

 Crossophorus, which was pointed out above as being presumably the most primitive type of 

 this sub-family. 



The occurrence of glandular fields on the upper lip in both Cypridininae, 

 Philomedinae and Asteropidae seems, of course, to support an assumption of the primitiveness 

 of this character. 



With regard to the eventual primitiveness of the selvage of the shell in 

 the Philomedines and Asteropids I content myself with referring to what 

 has been stated above. 



Other characters in Philoniedes could be brought forward, in which this genus agrees more 



closely with the Asteropids than does the sub-family Cypridininae. Among these the 



following may be mentioned: 



The first antenna: The second joint always has a distal-lateral bristle; the 

 pt)sterior edge of the original fifth joint is in the male so much shortened that the sensory 

 bristle of this joint seems most frequently to be placed next to the posterior-distal bristles 

 of the fourth joint. In the males the bristles of the distal joints are always without suctorial 

 organs; the c- and f- bristles (cf. the terminology for the sub-family Philomedinae) are very 

 much lengthened in this sex. 



The second antenna: The endopodite is always developed as a clasping organ 

 in the males. 



The penis is always of about the same type, small with weak musculation, more 

 or less clearly bifurcated distally. 



It is, however, to be noted that at least some of these characters may be considered old. 



presumably belonging to the ancestral forms of C y pr id inif urines. Such characters are: the 



absence of suctorial organs on the first antenna in the male, tlic dev.elopmeut of the endopodite 



of the second antenna as a clasping organ in the male (we find both these characters in the 



