THE UROCOPTID MOLLUSKS FROM THE MAINLAND OF 

 AMERICA IN THE COLLECTION OF THE UNITED STATES 

 NATIONAL MUSEUM. 



By Paul Baktsch, 



Assistaiit Curator, Dimsion of 3[oUusks 



The United States National Museum has from time to time received 

 additions to its collections of this group, some of which have been 

 reported upon by Dr. R. E. C. Stearns," Dr. William H. Dall,^ and 

 Dr. H. A. Pilsbry.'^ 



By far the greater part of the material added in recent years was 

 collected hy Messrs. E. W. Nelson and E, A. Goldman in their explo- 

 rations of Mexico, under the auspices of the Biological Survey of the 

 United States Department of Agriculture. Dr. J. N. Rose and Mr. 

 J. H. Painter, of the U. S. National Museum, and Dr. Edward Palmer 

 have also made some interesting discoveries of mollusks in their botan- 

 ical excursions in the same countr}-. The very latest donations have 

 come from Dr. H. Pittier, from Guatemala, and Prof. A. L. Herrera, 

 from Mexico. 



The two new forms from the United States were collected by Drs. 

 T. W. Stanton and T. Wayland Vaughan, of the United States Geo- 

 logical Survey, and Dr. Edward Palmer. 



This report would be incomplete without mentioning my indebted- 

 ness to Dr. William H. Dall, Curator of the Division of Mollusks, for 

 many kind suggestions, and to Dr. H. A, Pilsbry for critically com- 

 paring several forms with specimens in the Philadelphia Academy of 

 Natural Sciences. 



EUCALODIUM DECOLLATUM Nyst. 



There are two specimens of this species in the collection, Cat. No. 

 186131, U.S.N.M., collected by E. W. Nelson and E. A. Goldman, at 

 Teapa, Tabasco, Mexico. 



«Proc. U. S. Nat. Mus., XIII, 1890, pp. 208-211; XIV, 1891, p. 100. 

 & Nautilus, IX, 1895, No. 5; Proc. U. S. Nat. Mas., XVIII, 1895, pp. 3-5; XIX, 

 1896, pp. 344-357; Smith Misc. Coll. (Quart. Issue), XLVIII, 1905, pp. 187-190. 

 "Manualof Conchology, XV, 1903; XVI, 1904. 



Proceedings U. S. National Museum, Vol. XXXI— No. 1483. 



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