Sir

Your most interesting book on Worms¹ has given me a desire to observe their habits & will I hope be an excuse for troubling you about what I have observed—

A couple of weeks ago I noticed a worm of moderate size making its way across a large flag surrounded with grass at a side entrance of this house   Its course was straight until it came near to the end of the flag, when it turned its head & fore part to the right & at right angl to its course evidently to examine a hole which lay about an inch & a half at the right side of its course

The hole is 1$\frac{1}{2}$ inches square & 2$\frac{1}{2}$ inches deep—& was cut in the flag for a scraper, which has been removed—

It was filled with rain water to within an inch of the surface of the flag— The worm elongated its forepart & bent its head down in the hole till it reached the water which it seemed to taste—& after a short pause it drew its whole body down into the water & curled itself up round the inside of the hole— After a time it disappeared & on examining carefully I saw that there was some clay & sand at the bottom—(under the water) and into this it had worked its way out of sight—

In about half an hour it was lifted up out of the hole & again set free— again it went into the water & also into the clay as before

How long it remained there I unfortunately do not know—as when the hole was examined on a subsequent day the worm was gone

It appeared to me that the worm tho’ without eyes had some means of observing external objects,— otherwise I do not see how it c^d. have become aware of the existence of the hole which lay quite at one side of the track on which it was moving— There was no projection or any thing else to indicate the existence of the hole   It occurred to me that possibly its skin may be transparent enough to permit of its taking cognisance of objects near it.²

After half an hours immersion the worm was quite lively & went back into the hole again of its own free will—

I do not at all expect you to take the trouble of sending me any reply but thought possibly a statement of what I had observed might be of use or interest to you

I am Sir | Yours truly | A E Graves

Cha^s. Darwin Esq