154 The American Naturalist. (February, 
Contrast the foregoing with the following written from Kew, April, 
1887, to De Candolle. | Be | 
~ “ You will be a little surprised at the sudden transfer of Mrs. Gray 
and myself to England, but I wanted a vacation and one more bit of 
pleasant travel with Mrs. Gray while we are both alive and capable of 
enjoying it. Whether I shall lookin upon you at Geneva is doubtful, but 
it may be even for a moment. We never expect to have repeated the 
pleasant work at Geneva of the spring of 188!. We expect to go to 
Paris in May, but subsequent movements are uncertain. Always dear 
De Candolle, affectionately yours.” | 
© These volumes will always be interesting to American botanists, 
especially to those who enjoyed Dr. Gray’s personal acquaintance. 
CHARLES E. Bessey. — 
A Theory of Development and Heredity.‘—This volume 
recently issued by the Macmillans with the above title will no doubt 
find a good many readers. It is a book that deserves perusal, in that 
it presents with clearness the main issues that. are how agitating biolo- 
ogists, though the bias of the author is decidedly Lamarckian. In 
fact, it is probably the strongest popular contribution to the Lamarek- 
ian side of the controversy that has yet appeared. The author bane 
that in the first place the work is an effort to extend the application of 
‘the law of the conservation of energy to the phenomena of living mat 
ter, and to resolye the premises given by the science of physics to their 
¢onclusion in the realm of biology. How far he has succeeded may 
„be open to question, but his array of facts in support of his views 18 
certainly very creditable. Many of these facts have been known er 
a good while to biologists, but the author of the volume has brought 
them into their proper collocation in respect to each other and has 
made out a very strong argument in support of his position. In the 
sécond place, to use his own words, “itis the extension to all living 
matter of certain fundamental properties of life which psychology er 
either proved or tacitly assumed to exist in the higher animals. y 
here refers to the effects of repetition and association operating throug! 
a coérdinating nervous mechanism or system. His view of a 
evolution, is that it is a mechanico-psychological process. In io 
respect his views are closely similar to those of Cope published p 
since in a collected form—Cope’s view is that consciousness is t0 is 
regarded as an important factor in evolution, just how it opam 
‘ 4A Theory of Development and Heredity, by Herry B. Orr, Ph. D. Macmills? 
& Co., London & New York, 1893, crown 80, pp. ix and 255. °° 
