XII BIOLOGICAL SOCIETY OF WASHINGTON. 



Mr. Lester F. Ward read a paper on THE KING DEVIL.* 

 Discussed by Dr. Merriam and Messrs. Seaman and Ulke. 



Mr. Jno. B. Smith read a paper entitled SOME REMARKS ON 

 SEXUAL CHARACTERS IN LACHNOSTERNA.f Discussed by 

 Messrs. Ward, Ulke, and Mann. 



Dr. Theodore Gill gave a review of THE FAMILIES OF 

 FISHES. Discussed by Messrs. Ward, Mann, Stejneger, Dall, 

 and Fernow. 



ONE HUNDRED AND THIRTY-FIRST MEETING, 

 November 3, 1888. 



The President in the chair, and twenty-one members present. 



Mr. F. H. Knowlton presented a paper on FOSSIL WOOD 

 AND LIGNITES OF THE POTOMAC FORMATION. J 

 ^ Mr. W. H. Dall read a paper entitled THE MODIFICATIONS 

 OF THE GILL IN UNIVALVE MOLLUSKS. 



Dr. Theodore Gill described THE CHARACTERISTICS OF THE 

 FAMILY SCATOPHAGID.E. 



Dr. C. Hart Merriam described A NEW SPECIES OF ARVI- 



COLA FROM THE BLACK HlLLS OF DAKOTA. 1 1 



ONE HUNDRED AND THIRTY-SECOND MEETING. 

 November 17, 1888. 



The President in the chair, and forty persons present. 



Mr. Lester F. Ward read a paper on A COMPREHENSIVE 



* 1889. Botanical Gazette, Vol. XIV, pp. 10-17, January. 



t 1888. Insect Life, Vol. I, p. 180, December. 



J 1888. The American Geologist, Vol. Ill, No. 2. pp. 99-106. 



I 1889. Results incorporated in Report on Blake Gasteropods, Bull. 

 Mus. Comp. Zool., Vol. XVIII. 



|| 1888. Merriam, C. Hart. Description of a New Species of Meadow 

 Mouse [Arvicola longicauda} from the Black Hills of Dakota <Am. 

 Nat., Oct. 1888, 934-935, figs, of teeth. 



