138 PROCEEDINGS OP THE ACADEMY OF 



June 4. 



The President, Dr. Ruschenberger, in the chair. 



Twenty-two members present. 



The following papers were presented for publication : 



" Descriptions of Twenty-nine species of Unionidse from the 



United States." By Isaac Lea. 



"A Contribution to the Ichthyology of Alaska." By Edw. D. 



Cope. 



Note on Gamasus of the Ox. Prof. Leidy read an extract from 

 a letter from Dr. C. S. Turnbull, in which it was stated that the 

 writer had been misunderstood in relation to the Acarus of the 

 Ox, described in the Proceedings for January 2d. He had seen 

 the cattle killed, and was positive that the mites occupied the 

 position in the ear of the steers while these were alive. Such 

 being the case, the acarus may be viewed as a parasite of the Ox, 

 and may be specifically named Gamasus auris. 



Mr. Thomas Meehan presented some specimens of the common 

 asparagus, and remarked that in consequence of observing last 

 year so many plants that had evidently flowered, producing no 

 seeds, he had this year examined them in a flowering condition 

 and found them perfectly dioecious. Imperfect stamens existed 

 in the female flowers, but they were never polleniferous. An occa- 

 sional gynoecium in the male flower would make a weak attempt 

 to produce a pistil, but no polleniferous flower ever produces a 

 fruit. There was a great difference in the form of the male and 

 female flowers. The former were double the length of the latter, 

 and nearly cylindrical, while the female flower was rather cam- 

 panulate. Other observers had nearly made the discovery of 

 division in this plant. The old " English Botany" of Smith gave 

 it the character of being occasionally imperfect, and the authors 

 of " Deutchland Flora" considered it as occasionally Polygamous. 

 But Mr. M. w y as satisfied from a half day's investigation among 

 many plants that in this region at least the asparagus is never 

 perfect, but truly dioecious. 



He had observed another matter, small, but which might be of 

 importance to systematic botanists, as well as to those engaged in 

 evolutionary studies. One flower had a quad ri fid stigma, and a 

 four-celled ovary. The trinatc type, or its multiple, is so closely 

 associated with the endogenous structure, that he considered this 

 circumstance particularly worthy of note. 



The male flowers seem very attractive to insects, various kinds 



