1889.] natural sciences of philadelphia. 155 



June 4. 

 Mr. Theo. D. Rand in the chair. 

 Twenty-nine persons present. 



June 11. 

 Rev. H. C. McCook, D. D., Vice President, in the chair. 

 Twenty-seven persons present, 



A paper entitled " Description of new species of fossil Crustacea 

 from the Low T er Silurian of Tennessee with remarks on others not 

 well known," by J. M. Saflbrd and A. W. Yogdes was presented for 

 publication. 



June 18. 

 Mr. Harold Wingate in the chair. 

 Twenty-six persons present. 



The death of Mr. Geo. Y. Shoemaker, a member, was announced. 



The proceedings of the Biological and Microscopical Section 

 having precedence the following communications were made in 

 connection therewith : — 



Heterocercy in Batrachia. — Prof. Ryder remarked that in some 

 larvae of Amblystoma, species not determined, the tip of the tails of 

 individuals from one to two weeks old were drawn out into an 

 acute point ; this acute point was invariably flexed upward. This 

 fact is of interest since it may be a transitory or evanescent exhibi- 

 tion of traces of the heterocercal condition seen in the tails of fishes. 

 If it is to be so interpreted, it would seem that somewhere in the re- 

 mote past the Urodelous Batrachians had a heterocercal fish-like 

 ancestor. 



The Hypertrophied Hairs on Ampelopsis. — Prof. Ryder remarked 

 that he had lately noticed that some of the hairs on the leaves, 

 petioles and tendrils of Ampelopsis trieaspidata or Veitehii, hort. 

 were very greatly enlarged. These hypertrophied hairs as they 

 proved to be, have no uniform distribution. Their development 

 is anomalous and some young leaves and tendrils are without 

 them. They are found only on the young growing shoots of the 

 plant. These hairs are covered with an epidermis inclosing a few 

 very large, thin-walled cells. They are colorless and contain 

 little or no chlorophyll. They vary greatly in form. What their 

 function is was not made out. 



