See Letters 110 and 120.) This sentence was omitted in the subsequent editions, owing to the advice of Prof.Owen, as it was liable to be misinterpreted; but I have always regretted that I followed this advice, for I still think the view quite reasonable.
LETTER 306.

TO A.HYATT.Down, May 8th, 1881.
I am much obliged for your kind gift of "The Genesis, etc." (306/1.

"The Genesis of the Tertiary Species of Planorbis," in the "Boston Soc.

Nat.
Hist.

Anniversary Mem." 1880.), which I shall be glad to read, as the case has always seemed to me a very curious one.