THE NAUTILUS. 33 



NOTES. 



The Verrill Collection Prof. A. E. Verrill of Yale Uni- 

 versity has sold to the University his great collection of marine 

 invertebrates, acquired during his work for the United States Fish 

 Commission in the 16 years from 1873 to 1887. The collection is 

 the duplicate of one secured at the same time and since transferred 

 to the National Museum of ihe Smithsonian Institution at "Wash- 

 ington. 



Formation of epiphragm by Lymn^a palustris (Miiller). 

 — A few days ago while collecting fresh-water shells in the dry bed 

 of a pond near Alum Rock Park. San Jose, the author found several 

 live specimens of a form of Lym7ia;a palustris MuWer lying on the 

 dry mud surface with the aperture sealed down by thick dried 

 mucous and withdrawn into their shells half a whorl. The pond 

 usually contains water at least half the year but on account of the 

 dry spring has contained none since April 1st at least. The bed is 

 thinly covered with tall tulas so that the shells were not in the direct 

 rays of the sun. This form is the only one which occurs in the lake 

 and dead shells up to barely mature are abundant, and some larger. 

 — Harold Hannibal, San Jose, Cal. 



Exotic Vivipara in California. — Amongst the fresh-water 

 moUuscan fauna of the " Artesian Belt," between San Jose and San 

 Francisco Bay, is a large operculate edible snail introduced by the 

 Chinese fifteen or twenty years ago. 4 mm. when born, carinate 

 till mature, 6 months 20 mm. Occasionally in sub-brackish water, 

 grows as large as a duck's egg. Plain yellow-green or with spiral 

 fringes of epidermis. 



Specimens were sent to Dr. Dall, who identified it as Vivipara 

 lecythoides Bens. 



It is very common where planted, but spreads slowly. 



In the Nautilus XV, p. 91, is a reference to Vivapara stelma- 

 phora Bgt., from a dry bed of a lake or pond " at the foot of Mt. 

 Hamilton." The author has been over the San Jose, Mt. Hamilton 

 road collecting, and of the four lakes and ponds on the route only 

 one, on the Grant ranch in Hall's Valley, appears to answer the de- 

 scription, as it had been dry at the time that article was written for 



