My dear Darwin

Having been “drawn out” at the last meeting of the Entomological Society on the subject B’s cells, I was called upon by the Secretary to furnish some notes of what I said, in order that it might be inserted in the minutes—¹ I of course made the notes as short as possible & to do so, confined myself almost entirely to the theoretical part of the matter—indeed I felt obliged to keep as near as possible to what I really did say— I happened to have used the word “accidental” in con-nexion with the hexagonal form of cell, and as that was one of about 6 words which I had said, somebody got up & begged I would explain what I meant by using that term. so came a short explanation— after the Secretary has copied out my notes into the minute book I will get them back again & send them to you.

You say that the case of the Icaria bothers you,² furnishing a considerable difficulty, & I must say I was much surprised at it, but after all, the cell with the free angular sides is in contact with other cells in one part of its circumference, and this circumstance it appears to me furnishes a key to the difficulty, especially when we call to our remembrance the way in which the new cells are added to the edge of the comb—always in the interstices of two cells—the first atom of material that is laid down to commence a cell is stuck in the entering angle— Theoretically speaking I say that the cells of the wasp are cylinders altered into hexagons as they proceed—excepting, (generally) the case of the outermost tier, and that tier we must bear in mind is close up to the side of the nest—

I think I might safely have said always instead of generally, if I had defined the outermost tier of cells in the comb as that tier which is so near to the side of the nest as not to admit of work being carried on beyond it— The exceptional cases, it appears to me almost certain, occur only where there is a little more space than usual owing to irregularities in the outline of the nest—here the cells are altered into the hexagonal form, altho’ other cells are not formed externally to them, so that in fighting for mere words, it might be objected to my theory,—that the contact with other cells is not a necessary condition to produce angular cells— I am ready to fight this point out— I ought here to say that if the word “not” is left out in the above underlined sentence, that sentence gives the pith & marrow of my theory—

Fearing that I should have to make so many alterations in the part that follows, that you would scarcely be able to read it I took a separate sheet of paper to clear my ideas upon—it is, however, I hope legible so I send it—

Faithfully yours | Geo. R. Waterhouse