108 



■I'AC.K SKOCSHKRO 



Summary of this 

 chapter. 



Cupridinidce 



Halociipridce 



Cijtheridae 



C^prldoe. 



Y 



see in s a n v t h i ii g li ii t p r o h a li 1 c t h a t C. Clats' v i c w t li a ( 1 li e C y p i" i (1 s 

 h a V il V flop e d f r u in ni a r i n c ( ' y t h i" i' ids is c o r r e c t. But it is (juitc 

 impossible to solve this problem delinitoly in tiic present state of affairs. 



It see m s t o m e b y n o m e a n .s impossible t li a t dyprijorines h a v e 

 b r a n e h e il o f f f r o m the ancestors of t h e Hal o c y p r i d s a f t e r t h c 



1 a t t 1' I' h a (1 1) e c n d i I I' c r c n t i a. t e d 

 f r o m (' y p r i d i n i d s a n d J' o 1 y c o p i d s. 

 Tliis (juestion will only be able to be sol- 

 ved after the solution of the problem as to 

 whether the foliaceous type of the hflli and sixth 

 limbs of C y p r i d i n i d s is a primary or a secon- 

 dary one. A n u m b e i' o f f e a t n i' e s i n t h e 

 a n a t o m y of the P o 1 y c o p i d s see m t o 

 indicate that this g r o u j) branched 

 off from t h e other g r o vi p s at a v e r y 

 early stage, presumably before the 

 Cypridinids, and consequently long 

 before the time indicated in the 

 pedigree drawn up by G. W. MUller. () n the o t li e r hand it seems to 

 me quite impossiljle at present to decide when the original forms 

 of the C y t h e r e 1 1 i d s were differentiated from other ( ) s t r a c o d s. 

 It will be seen that the result of this e n q u i r >' has been to a great 

 extent negative. Only in a comparatively few respects has it seemed to me possible 

 to follow more or less without reservations the views of previous writers as to the organization 

 of the Protostracods and the natural grouping of the recent Ostracods; in 

 most cases I have been compelled to doubt or even to reject the suggestions made by them. 

 I did not think I could construct any ..genealogical tree", nor did it seem possible to accept 

 any of those previously drawn up. I have only been able to bring a small number of new facts 

 into the discussion. This is due especially to the fact that only a few phylogenetically important 

 forms have been included in the literature of late. Only one such form has, as far as I know, 

 been added; I refer to the curious genus Thaumatocypris. But I hope that this investigation 

 will not prove to be of no importance. 



Fig. X. — The pedigree of the recent Ostracods 

 according to C. Claus' statements. 



