1889.] NATURAL SCIENCES OF PHILADELPHIA. 311 



formation are a variety of very interesting iron ores, shales, fire clays 

 and mineral paints which deserve further notice. 



October 8. 



Mr. Charles Morris in the chair. 



Twenty-six persons present. 



A paper entitled, " New and Little-known American Mollusks, 

 No. 2," by H. A. Pilsbry, was presented for publication. 



The Antennas of Coleoptera. — Dr. Geo. H. Horn spoke of the 

 structure of the antenna? of coleoptera and of their being the seat 

 of a special sense, the exact nature of which is not definitely de- 

 termined. 



The locality of the sense is indicated by some peculiar surface 

 sculpture and may be either generally diffused, concentrated in 

 spots or limited to a small number of joints. As a general rule in 

 those families in which the diffusion is general there is little or no 

 variation in the total number of joints, while in families with a few 

 terminal joints sensitive the basal joints vary in number within 

 generic and specific limits, and at times the individual specimen 

 may have the two antenna? unequal. 



The view was expressed that, in those families with the concen- 

 tration of the special sensory faculty in a few terminal joints, 

 as in Scarabaeidae, Hydrophilidae and some Ptinidae, the entire 

 number of joints in the antenna? should be used with extreme cau- 

 tion as a character for generic separation, without the presence of 

 some supplementary characters. 



October 15. 

 The President, Dr. Joseph Leidy in the chair. 

 Thirty-two persons present. 



October 22. 

 Mr. Charles Morris in the chair. 



Twenty-one persons present. 



A paper entitled, " On a new species of Spider of the Genus 

 Dinopis from the Southern United States," by Dr. Geo. Marx, was 

 presented for publication. 



