970 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXVI. 



at most Cyjyr'niotm should have but the rank of a division of the 

 genus Cypi'ls. 



Furtheiniore. 1 entirely agree with the observations of Kaufmann 

 where he saj's: 



Ebenso ist das vorhandsein einer Tuberkel-reihe auf dem Shalenrand ein Gattungs- 

 merkinal von sehr fraglichcn Wert, da es eben ein rein ilusserlichea ist, und was fiir 

 bedenklic'he Folgcn eine Beri'ickMicbtigung solcber rein ilusserlioher Meikniale in der 

 Systematik herbeifiihrt, haben uns de Diagnosen iilterer Antoren zur Geniige gelehrt. 



The tubercles also seem to be quite variously present on both right 

 and left valves, and regardless of the method of propagation. 



I shall therefore regard the genus CyprmotuK as a subgenus of the 

 genus Cypriti., the genera Iletemcypris Claus and Aiiiphlcyprh Sars 

 being similarly used and for similar reasons (see key, genus Cypris). 



All species of Cijprh that are evidently sexual and have a row of 

 tubercles on the right shell margin should fall in the Cyprinotus 

 group. Those seemingly sexual and armed with tubercles on the left 

 valve margin and with ''pore canals" should fall under the Ileterocy- 

 pi'i.s group. Provisionally it seems necessary to establish another 

 subgenus, with Cypris grandis Chambers as the typt^ Insufficient 

 data, howevei', makes this division a dou})tful one. All other forms 

 of Cypris not included in the above four subgenera will here be 

 classed in Cypris proper. 



Of the nine species described in this report, I have been enabled to 

 identify seven with forms already recorded. The remaining two 

 species, as also the genus Spirocypris., 1 regard as new to science. 

 As a whole, the nmseum collection so far affords an addition of three 

 genera and tive species as new to the United States, and of these all 

 l)ut Chlamydotheea as new to America, this genus being originally 

 described from Mexico. 



I owe thanks to Dr. S. A. Forbes, of the University of Illinois, for 

 loan of literature; to Dr. Richard Rathbun and Mr. Charles T. Simp- 

 son, of the U. S. National Museum, for loan of material, and to Dr. 

 A. C. Eyclesheimer and Mr. C. C. Adams, of the Universit}^ of Chicago, 

 for many courtesies extended. 



SYSTEMATIC SUMMAEY. 



The fresh- water Ostracoda of the U. S. National Museum are distrib- 

 uted as indicated in the following summaries. The species comprise 

 nine names, distributed in six genera and four subfamilies, as follows: 



