Dear Sir

I think the shell is Sphærium corneum but cannot be quite sure, it measures .35 of an inch from the beaks to front margin .45 of an inch from one side of the valve to the other, and .3 of an inch in depth and weighs .39 gramme.¹

I am sorry that the shell dropped off the bettle on Thursday 23^rd. inst afternoon and I caught it on the Saturday 18^th. inst. afternoon previous, it was very firmly fixed for the beetle shook it violently in its movements and a little while after they had separated the bettle dived to the bottom and its left antenne was caught between the valves and the bettle was held for a few minutes apparently unable to rise, in its original position the shell was on the right hand side of the bettle, looking down upon the bettle with the head away from the observer, on the 2^nd. or imtermediate leg, four joints of the tarsus were visible and the remainder of the foot measures .1 of an inch.

The beetle was captured in a small pond and was able to crawl easily through grass but it never attempted to fly that I am aware of sine I have had it, both the specimens are forwarded to you alive by accompanying post and I hope they will arrive safely, as you think the case worth communicating to Nature should be pleased to do so but should like to be certain about the shell first, if there is any other information you require I should be pleased to supply if possible²

Very truly yours | W. D. Crick

Chas Darwin Esq.