382 NOTES AND COMMENTS [DECEMBER 
Those who are seriously interested in the question would find 
food for reflection if they would take opportunity to become 
acquainted with “Nature Studies in Berkshire,’ by John Coleman 
Adams (New York and London: G. P. Putnam’s Sons, pp. 225, 1899). 
It is not that there is any new discovery in the book; it is the redis- 
covery of delight. It will probably not even instruct, but it may 
possibly enlighten. It is not an educational compendium; it is a 
work of art. In a beautifully bound and printed volume, with fine 
photogravures, and in a style which sometimes reminds one of 
Burroughs, the author tells us of the American Berkshire; and the 
titles of some of the chapters will suggest his happy mood: A Whisper 
from the Pines, The Seamy Side of Summer, At the Sign of the 
Beautiful Star, The Great Cloud Drive, The Fruitage of Beauty. He 
excels himself perhaps in “The Circumvention of Greylock,’ which 
means “a bicycle run round a hill,” but the difference between his title 
and ours is the difference between light and darkness. We have re- 
ferred to the book here because of our conviction that its value lies in 
its being an expression of delight in nature by a cultured gentleman, 
and that if “nature study” does not at least lead towards this, it is not 
likely to mean more than another millstone about the neck of youth. 
The Production of Parthenogenesis in a Sea- 
Urchin. 
Ir is not long since Delage made a remarkable experiment, which 
seemed to prove that the nucleus and centrosome of the ovum were 
not essential to reproduction. Now comes Professor Loeb of Chicago, 
and, likewise by actual experiment, makes out that even the spermato- 
zoon is not necessary. His results are given in a short note “On 
the nature of the process of fertilisation and the artificial production 
of normal larvae (plutei) from the unfertilised eggs of the sea-urchin” 
(Amer. Journ. Physiol. vol. iii. pp. 135-138, Oct. 1899), As the 
outcome of a long series of experiments and inductions, he was led to 
believe that the only reason why the eggs of marine animals did not 
develop parthenogenetically was that something in the constitution of 
sea-water prevented it. That something, he inferred from experi- 
ments on the contraction of muscles, was the presence or absence of 
ions of sodium, calcium, potassium, and magnesium. The two former 
require to be reduced, the two latter to be increased: “a great number 
of variations in this sense might bring about the desired effect.” 
Without going into details, Professor Loeb states briefly that “the 
3 10 : 
mixture of about 50 per cent 3 MeCl, with about 50 per cent of 
