PHYSA. 119 



They make little nests of transparent jelly, filled 

 with minute eggs, and attach them to the side of the 

 jar, where you can easily watch the development of 

 the embryos. In my jar the little things came out 

 after twenty days, each with a perfect shell, and 

 began life on their own account. Suppose you put 

 such a jar in your school-room. 



This species, as well as the last, has many varie- 

 ties — as ancillaria^ propinqua^ diaphana and virginea. 



Physa politisswia^ Try on, from Oregon, has a bril- 

 liant shell with a dark line near the edge of the outer 

 lip. I should consider it but a variety of the wide- 

 reaching heterostropha. 



This last name is the Greek for " turning- the- 

 other-way," though all the Physas have sinistral 

 shells and may thereby be recognized at the first 

 glance. 



Physa costata^ Newc, cos-ta'-ta, has a very small, 

 thin shell, with a somewhat ribbed or corrugated sur- 

 face. From Clear Lake, California. 



Physa Gabbi^ Tr}^on. Spire small, consisting of 

 three or four minute whorls. Body whorl large, 

 aperture large also, outer lip broad and full. Speci- 

 mens from Portland, Oregon, are light horn-colored, 

 and from one-half to a whole inch in length. 



Physa Carltonii^ Lea, Carl-to'-ni-i. Body whorl 

 full and round, horn-colored; outer lip marked inter- 

 nally with stripes of dark brown; length, three- 

 fourths of an inch. From near iVntioch, California. 

 Named in honor of its worthy discoverer, Mr. H. P. 

 Carlton. 



Physa Coopei^i^ Try on, Coop^-er-i, named for 

 another eminent conchologist, has a small, slender 



