72 THE NAUTILUS. 



ANNOTATED LIST OF THE RECENT BRACHIOPODA IN THE COL- 

 LECTION OF THE UNITED STATES NATIONAL MUSEUM, WITH DE- 

 SCRIPTIONS OF THIRTY-THREE NEW FORMS. By William H. 

 Dall (Proc. U. S. Nat. Mus., 1920, Vol. 57, pp. 261-377). The 

 collection of recent Brachiopods in the National Museum is 

 unusually strong, containing 181 different forms, represented 

 by over 6,000 specimens, including many original types. 



ON THE ANATOMY OF PALUDESTRINA JENKINSI. By C. G. 

 Eobson (Ann. Mag. N. H., 9 ser., V, May, 1920). This species 

 has long been of interest on account of its rapid spread 

 through the waterways of England, Wales and Ireland, and 

 recently from the discovery that it is apparently partheno- 

 genetic. It has a large crystalline style. There is a well- 

 developed pedal gland as in Valvata. In the ovary were seen 

 oocytes but no spermatozoa. There is also an organ corres- 

 ponding to the sperrnatheca. The capacious brood-pouch is 

 excavated in the pallial integument of the right side, and 

 capable of holding over 40 young. The writer has already 

 suggested that P. jenkinsi is a Potamopyrgus; it should be 

 compared with some of the tropical species, none of which 

 have been dissected. H. A. P. 



THE RADULA OF THE MITRID/E. By Rev. A. H. Cooke (Proc. 

 Zool. Soc. London, 1919 [1920], pp. 405-422, 18 figs, in text). 

 A valuable contribution to our knowledge of the radula of 

 this family. The work is based largely on the collection of 

 the late Prof. H. M. Gwatkin. 



COSTA RICAN LAND AND FRESHWATER SHELLS. By H. A. 

 Pilsbry (Proc. Acad. Nat. Sci., 1920, pp. 2-10, 6 figs, in text). 

 The paper is based on a collection made by Dr. P. P. Calvert 

 and Mrs. Calvert in 1909 and 1910. Five new species are de- 

 scribed. C. W. J. 



