THE NAUTILUS. 



valves are preserved in place, with fragments of the girdle. The 

 valves lack insertion-plates, and also otherwise have the general 

 characters of the modern Lepidopleurus, while the girdle is armed 

 with spines which are believed by Jaekel to have been calcareous. 

 The length, without girdle, is about 16, breadth 9 mm. The genus 

 is evidently extremely like Lepidopleurus in hard parts, and so far as 

 the figures and description show, indistinguishable from the recent 

 genus except in the character of the girdle armature. It is quite 

 unlike any of the known Palaeozoic genera. — H. A. P. 



PUBLICATIONS EECEIVED. 



Synopsis of the Family Cardiid.e and of the North 

 American Species. By William Healey Dall. Proc. U. S. 

 Nat. Mus. Vol. xxm, pp. 381-392, 1900.— As Tryon and Pils- 

 bry's " Manual of Conchology " does not yet include Pelecypoda. the 

 necessity for monographs giving the latest investigations in system- 

 atic changes is apparent. Students are deeply indebted to Dr. Wm. 

 H. Dall for his recent monographs on several families of bivalve 

 mollusks, including the Mactracea, Diplodontidae, Leptonacea, Psam- 

 mobiida?, Solenidas Tellinidae and Cardiidae. 



In the bulletin on Cardiids" there are no plates, but there is a bibli- 

 ography followed by a synopsis of the family which includes a " sub- 

 division of the family included as a whole." The "brackish water 

 forms associated with Adaena" are no longer included in this family. 



The principal changes in nomenclature of the East American 

 species since Dr. Dall's "Marine Mollusks of the South Eastern 

 Coast," are as follows : 



Cardium magnum Born is included under the name of C- (Diun- 

 cardiuni) robustum Solander, which is the older name ; this does not 

 include G. magnum Linnaeus, which Dr. Dall thinks is probably C. 

 [Trachycardiurn) leucostoma Born. In subgenus Papyridea, spiim- 

 sum takes the place of bullatum, or bullata, of " many authors but not 

 of Linnaeus," and P. petitianum Orbigny is a synonym of P. semimil- 

 caium Gray. Liocardium Icevigatum is a synonym of Cardium 

 f Lcevicardium) serratum Linnaeus. 



The West American species include Cardiums found in the Gulf 

 of California and ranging further south. This adds to the number 

 of West Coast species. 



