112 THE NAUTILUS. 



secure location where the water was not too deep, and fish with a 

 silk butterfly net attached to a long handle. When a shell was 

 sighted the boat was brought to a standstill so the surface would be- 

 come quiet, and the net was lowered with the edge of the wire beneath 

 the shell. As soon as the shell was touched the animal let go all 

 hold, and if it did not roll into the (olds of the net would settle 

 among the large pebbles. To secure it then in three or four feet of 

 water was impossible. Naturally, the failures were as frequent as 

 the successes. As stated, the afternoon produced a couple of dozen 

 shells, two dripping individuals, each with aching backs and weary 

 eyes, and a torn net and wet boat. 



Aplexa hypnorwn L., var. tryoni Currier. 



The Bitter Root river valley flows to the north along the flank 

 of the Bitter Root mountains, which are on the western bank. 

 From these mountains numerous creeks enter the river, and many 

 ponds have been made by these creeks and by the changing river, 

 the river is about 100 miles long, and flosvs through one of the finest 

 and most fertile valleys in the State. In one of these ponds, near 

 the juncture of the Bitter Root and Missoula, this species was found 

 rather abundantly. 



Physa heterostropha Say (?). 



Specimens referred by Dall to this species were collected at 

 Missoula in June, 1898, September 17, 1897, and April 8, 1900, on 

 which latter date they were depositing eggs. In working over the 

 Physa collected in Western Montana, I have read with much inter- 

 est the complaint of O. A. Crandall in THE NAUTILUS for June, 

 1892, in which he raises the question, "Is there such as species as 

 that described by Say? If so, what is it?" 



Physa ampiiUacea Gld. 



The species seems widely distributed in Western Montana. It 

 has been taken in Bitter Root river, in Lakes Sin-yale-a-min and 

 McDonald in the Mission mountains, and sparingly in Flathead lake. 



Physa gyrina Say. 



A few of this species taken with P. heterostropha and P. ampullacea. 

 Finding these three species together leads to suspicion that the 

 species may not be distinct. A single shell from the Flathead In- 

 dian reserve (Crow creek) seems to belong to this species. 



