206 PROCEEDINGS OF THE ACADE\nr OP [Mch,, 



March 7. 

 The President, Samuel G. Dixon, M.D., in the Chair. 



Fifteen persons present. 



The deaths of the following meml^ers were announced: Edward 

 Longstrcth, February 24, 1905, and J. Dundas Lippincott, March 6, 

 1905. 



The Publication Committee reported that papers under the following 

 titles had been presented for pulilication: 



"Senility among Gasteropods," by Burnett Smith. 



"Notes on some Arctic Fishes, with Description of a New Onco- 

 cottus," by Henry W. Fowler. 



The Utility Principle in Relation to Specific Characters. — Mr. 

 Arthur Erwin Brown made a communication of which the follow- 

 ing is an abstract: 



By way of introduction to an argument supporting a broad view of 

 the factors of evolution, such as that taken by Darmn, against the 

 exclusive valuation of Natural Selection urged by Neo-Darwinians, 

 the speaker mentioned that Charles Darwin was elected a corre- 

 spondent of the Academy on March 27, 1860, the Origin of Species 

 having been first published in London on November 24, 1859, and 

 the following extract was read from a letter written by Darwin on 

 May 8, 1860, to Sir Charles Lyell: "This morning I got a letter from 

 the Academy of Natural Sciences of Philadelphia announcing that I 

 am elected a correspondent. It shows that some naturalists there 

 do not think I am such a scientific profligate as many think me here." 



The Academy appears to have been the first among scientific socie- 

 ties to confer its honors upon Darwin after the publication of his 

 immortal work. 



The opinion of Alfred Russell Wallace as a leading advocate of Neo- 

 Darwinism, that utility has necessarily been the sole factor in the pro- 

 duction of specific characters, was contrasted with Darwin's view, and 

 the difficulty of bringing facts to bear against a logical proposition 

 constructed in the form of a closed circle was pointed out. Many biol- 

 ogists have been led by this difficulty to the hasty conclusion that it is 

 useless to cite cases of apparent inutility in face of it ; but this view is 

 unfortunate, for thereby the field is abandoned to the advocates of 

 exclusive utihty. Furthermore, the accumulation of probabilities by 

 means of such cases is not only legitimate as a method, but at the pres- 

 ent time is about the only one by which the argument can be met. 



