Sir,

In your work “The Descent of Man” &^c. second edition 1875. page 45,¹ occurs a passage as follows viz:

“I have shewn in a former work that all our domesticated quadrupeds and birds, and all our cultivated plants, are more fertile than the corresponding species in a state of nature. It is no valid objection to this conclusion that animals suddenly supplied with an excess of food, or when grown very fat; and that most plants on sudden removal from very poor to very rich soil, are rendered more or less sterile”. With reference to the sudden supply of an excess of food being a cause of sterility. I would mention that a friend in whom I have perfect confidence, a close observer of nature, one who has been familiar with sheep all his life, and who is well known in his neighbourhood as a successful sheep breeder has mentioned to me several times that he has the power of obtaining twins and triplets in his flock or the reverse, his plan is that at the time of conception, he raises the tone of their system by a sudden supply of improved feeding stuff than they have been accustomed to— this plan he has put into practise many times and almost always successfully.—

If his explanation of the fact of his producing twins be correct then it appears as if the objection in the text ceases to be of any value.

However small a fact may be, if it be a fact will excuse my intruding upon your time.

I remain Sir— | Yours truly. | R. W. Griffiths.