PROCEEDINGS. XXXI 



by the president, Dr. J. C. Welling, at the annual meeting of 

 that Society. The invitation was accepted. . 



Dr. W. K. Brooks, of Johns Hopkins University, made a com 

 munication upon THE ORIGIN OF ALTERNATION OF GENERATION 

 IN THE HYDRO-MEDUSAE.* 



Mr. Sanderson Smith, of New York, read a paper entitled 

 THE RECENT EXPLORATIONS OF THE STEAMER ALBATROSS, 

 WITH SPECIAL REFERENCE TO THEIR GEOLOGICAL TEACHINGS. 



SIXTY-NINTH MEETING, December 13, 1884. 



The President occupied the chair, and thirty-six members were 

 present. 



The following communications were made . 



Mr. Leohhard Stejneger, THE SHEDDING OF THE BILL IN 

 AuKs.f 



Dr. George Vasey, THE GRASSES OF THE ARID PLAINS, an 

 account of observations during a recent trip to the western part of 

 the United States. 



Mr. C. D. Walcott, THE OLDEST KNOWN FAUNA ON THE 

 AMERICAN CONTINENT,! a description of the characteristic fos 

 sils of the Primordial Group, of St. John, New Brunswick. 



Prof. L. F. Ward, THE OCCURRENCE OF THE SEVENTEEN- 

 YEAR LOCUST IN VIRGINIA, IN OCTOBER, i884, and ADDITIONS 

 TO THE FLORA OF WASHINGTON DURING 1884. || In his second 



* Abstract of a memoir entitled The Life History of the Hydro-Medusa ; 

 a Discussion of the Origin of the Medusce, and of the Significance of 

 Metagenesis, now in course of publication by the Boston Society of Nat 

 ural History. 



t 1885. <Results of Ornithological Explorations in the Commander 

 Islands and Kamtschatka, by Leonhard Stejneger. Bulletin of the U. S. 

 National Museum, No. 29, Washington, 1885, pages 25-62, pis. i-v. 



J 1884. WALCOTT, CHARLES D. On the Cambrian Faunas of North Amer 

 ica. Preliminary Studies. Review of the Fauna of the Saint John Forma 

 tion contained in the Hartt Collection at Cornell University. Bull. U. S. 

 Geological Survey, No. 10; Washington, 8vo., pp. 56, pis. i-x. 



1885. WARD, LESTER F. Premature Appearance of the Periodical 

 Cicada. <Science, v, June 12, p. 476. 



|| 1886. Proc. Biol. Soc. Washington, viii, p. 106. 



