Stiidifs on m.iriiK' Oslrncnds ' 189 



So far seven* genera ol tliis group have been established, namely: 



Cypridina, H. Mhae Edwards, 1840. 



Monopia**, C. Claus, 1873. 



Crossophorus, G. S. Brady, 1880. 



Pyrocypris, G. W. MUller, 1890 (= Eupathisloma, G. S. Brady, 1898, p. 437). 



(licjantocypris, G. \V. MtLLER, 1895. 



Codnnocera, G. S. BRADY, 1902 a. 



(hipridinodes, G. S. Brad^'. 1902 a. 



Of these it seems as if the genera Crossophorus, Gigantocypris and Codonocera may 

 without hesitation be characterized as natural classificatory units, well defined from 

 each other and from other genera, as has already been pointed out bv (J. \\\ MflLLER, 

 1906 b, pp. 12 and 13. 



The genus Pyrocypris (= Cypridina, s. str., et s. meo) comprises a lather large number 

 of very closely related species. These species are presumably more closely related to the forms 

 that have been grouped by G. W. MiiLLER under the name of Cypridina than are the three 

 above-mentioned genera Crossophorus, Gigantocypris and Codonocera. This does not. however, 

 prevent their breaking-out as a higher systematic unit from being considered as ([uite 

 justified. G. W. MOller himself seems, however, to have had doubts as to the correctness 

 of establishing this genus; he writes on this point, 1906 b, p. 13, as follows: „Die Gattung 

 Pyrocypris .... steht der Gattung Cypridina s. str. viel naher als die genannten" (Crosso- 

 phorus, Gigantocypris and Codonocera), ,,man kann in Zweifel dariiber sein. ob nicht manche 

 Vertreter von Cypridina ihr iiiiher verwandt sind als anderen Vertretern der Gattung. und oh 

 ihre Abtrennung die natiirliche Verwandtschaft zum Ausdruck bringt." Then he adds: ..Auf 

 jeden Fall vereinigt sie eine groBere Zahl nahe verwandter Form, liiRt sich audi scharf 

 characterisieren." — In his last large synoptic wor-k on the O s t r a c o d s. 1912. this 

 investigator certainly quite correctly retains this unit, in spite of this doubt of his. In tlic 

 present work I have followed him in this procedure with the exception that the group in 

 question has been considered a sub-genus of the genus Cypridina***. 



Of the three remaining genera, Cypridina, Monopia and Cypridinodes, G. AV. M('i.Li:r 

 always rejects the two latter; all three are united by this author under the generic name Cypri- 

 dina. He gives the following reasons for this method of procedure of his (1906 b, p. 13): 

 ,, Anders ist es bei den folgenden Gattungen: Monopia Claus charakterisirt (lurch das umfang- 

 reiche Frontalorgan. Beriicksichtigen wir nur das Frontalorgan, so reiBen wir niiclist verwandte 

 Formen, wie z. B. C. flaveola Claus and /ariis Brady = Cypridinodes favus Brady auseinander. 

 BRAD^ hat 1. c. die Gattung Cypridinodes aufgestellt, doch IxTulit seine Charakteristik ganz 

 oder fast ganz auf Beobachtungsfehlern: an der Maxille sind die auch bei anderen Vertretern 

 der Gattung Cypridina kurzon Kaufortsatze der Maxille abgcri.ssen, der schlanke Maxillartaster 



* With regard to the gonus I/elrrodi'smiis. G. S. liitAnv. IXfiS h, il'. below under the sub-genus Stp/ionoslra. 

 *• In a later work. 1891 b, note p. 10 C Cms altered this name to Eumonopin ,.da Ijibbock bereils friiher 

 eine Po n t e I li d e n-Oattung Mnimp^ genanni hatte". There seems to me to be no reason for following this ehange 

 of name. 



With regard to the name of this sub-genus see lielow |). 192. 



*** 



