NATURAL SCIENCES OF I HILADELPHIA. 315 



The deaths were announced of Mr. Francis A. Wolgamuth, a mem- 

 ber, and of Dr. Robert W. Gribbes, of Columbia, S. C, correspondent. 

 Also that of Mr. Robert Kennicott, correspondent, which occurred near 

 Behring's St. aits. 



November 13^. 



The President, Dr. Hays, in the Chair. 



Thirty-five members present. 



The following was offered for publication : " Description of the 

 Hot Springs of Soda Creek, &c." By E. L. Berthouul. 

 Mr. Isaac Lea read the following letter : 



New Garden, 5th of Oth mo., 1866. 

 Isaac Lea. 



Dear Friend, As science is the accumulation of facts, and the legitimate 

 inductions derived from them, I offer no further apology for this intrusion. 



Our Helieidse and other land shells generally pass the day in damp secluded 

 places, among grass, under logs and fallen leaves, and even buried beneath the 

 surface of the earth in dry weather, and are consequently difficult to find. 

 From these retreats they sally forth during the night, enlivened by the falling 

 dew or still more by a shower of rain in quest of food and pleasure. But 

 here they are screened from observation by the darkness of the night. 



Knowing their habits, and having often found them under boards or other 

 dejected matter, it occurred to me several years ago to make this knowledge 

 available in collecting such shells. My success has been most gratifying to 

 myself may it not prove equally so to others? "The plan which I adopted is 

 this : On a summer evening, after rain, I lay a wet board on the wet grass any- 

 where in my yard, lawn, or pasture, and on the following morning find the 

 shells adhering to the under surface. In this way I have at various times ob- 

 tained the following species in greater or less abundance : 



Succinea avara, Vallonia minuta, 



Hyaliua indentata, Bulimus marginatus, 



arborea, Leucocheila contracta, 

 Gastrodonta suppressa, corticaria, 



Strobila labyrinthica, peutodon, 



Anguispira alternata, Isthmia ovata, 

 Patula striatella, gouldii, 



Helicodiscus lineata, milium, 



Pseudohyalina minuscula, armifera. 



Only a week ago, on removing a small log from my pasture, where it had lain 

 some months, I accidentally detected a few shells of Isthmia milium, hitherto un- 

 noticed in this vicinity. The next evening, after rain, I laid three boards, each 

 four feet long and six inches wide, upon the spot, and the next morning ob- 

 tained 250 1st. milium, 15 Leuc. pentodon, 3 Gast. suppressa, and 6 Pseud, minus- 

 cula. 



The plan here suggested is susceptible of extensive application to the pur- 

 poses of the practical conchologist and travelling collector of shells, wherever 

 they may chance to pass the night ; especially so, as I have found by repeated 

 trials that a bucket of water thrown on the grass and covered with a board 

 affords all the conditions necessary for success about as well as a shower of 

 rain. No cumbrous apparatus is required to load the traveller; the means will 

 always be at hand wherever he may chance to lodge, and a few moments of 

 the evening and morning will suffice to set his traps and bag the game. 



The record of a journey across this wide continent, so conducted, would 



1866.] 



