108 



TAOE SKOGSBERG 



Swiiinary o/ llii^ 

 chapter. 



Cupridinida 



Haloci^pridce 



Cytheridoe 

 Cijpridce. 



see m s a n y t li i n g b n t p r o b a b 1 e t li a t C. Claus' v i e w t h a t t h e C y p rids 

 have developed from marine C y t li e r i d s is correct. But it is quite 

 impossible to solve this problem definitely in the present state of affairs. 



It seems to me by no means impossible that Cyfriform.es have 

 branched off from the ancestors of the H a 1 (j c y p rids a f t e r the 



1 a 1 1 e r h a d bee n d i f f e r e n t i a t e d 

 f r o m C y p r i (1 i n i d s a n d P o 1 y c o p i d s. 

 This question will only be able to be sol- 

 ved after the solution of the problem as to 

 whether the foliaceous type of the fifth and sixth 

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

 dary one. A n u m b e r of features in the 

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

 indicate that this g r o u ]) b r a n c li e d 

 off from the other g r o u p s a t a v e r y 

 early stage, presumably before the 

 f ' y p r i d i n i d s, and c o n s e q n e n 1 1 y long 

 before the time indie a ted i n t \\ e 

 pedigree drawn up by G. W. MiiLLER. n the o t her hand it see m s t o 

 m e quite impossible a t present to decide w h e n the o r i g i n a 1 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 enquiry has been to a great 

 extent negative. Only in a comijaratively 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 P r o t o s t r a c o d s 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 ujj. 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 Thaumatocijfris. But I hope that this investigation 

 will not prove to be of no importance. 



Fig. X. — The pedigree ol' the reeent O s I r a e n d s 

 accordiiir; to C. Claus' statements. 



