240 OYSTERS, AND ALL ABOUT THEM. 



Another enemy of the oyster, particularly when young, 

 is the ASTYRIS, discovered in Chesapeake Bay, near Cris- 

 field, Md., and described by Mr. U. H. Dall, of the 

 United States Coast and Geodetic Survey, in the Report 

 for 1881, as follows: 



" Only a few specimens were preserved, and hence it is 

 impossible to speak positively in regard to its distinctness 

 from the allied forms Astyris spirantha (Rav.), and A. 

 lunata, Dall (Ex. Say). It differs from the former, so far 

 as the specimens go, in colour, pattern, and solidity, having 

 also more whorls and a more slender form. It differs in 

 form very much from southern specimens of A. lunata, but 

 more specimens of each are needed to determine the limits 

 of variation in these small shells. They belong to a group 

 known to be extremely variable. It may for the present be 

 denominated by the varietal name Astyris, var. Winslovii, 

 in commemoration of its discoverer (Lieutenant Winslow). 

 Though known to be carnivorous, no species of the genus 

 Astyris has been recorded until now as an injurious 

 animal." (/) 



In the same Report, (/) Lieutenant Winslow says : 

 " During the season of 1878 we observed large numbers of 

 astyris in the shells of the mature oysters, and attached to 

 those of the young. In many cases they were found in 

 the holes which had been bored in the shells of the latter. 

 As we could not find any known enemy of the oyster in 

 sufficient numbers to account for the evident damage done, 

 and as so many circumstances pointed to astyris as the 

 cause, I concluded that the boring must be done by that 



animal, and alluded to it in my previous report 



During the past summer we have found a much larger 



(z) p. 81. (/) p. 70. 



