I 70 The American Naturalist. (February, 
I at once plucked the apple, and examined closely the identical spot 
where the beetle had been at work, and was surprised to find that there 
was no puncture to be seen in the skin of the apple, but only a minute 
brown speck, I found that the beetle had plugged the little opening 
with what appeared to be a bit of pomace, probably excrement, and 
she had done the work so nicely that I think no one would have sus- 
pected that this little speck marked the place of oviposition of this 
insect, unless he had seen such specks before, and knew what they signify. 
With a sharp knife a section was made through this egg-chamber, which 
I have endeavored to represent natural size, at F ig. 1, 5, with the egg 
at the bottom. ; 
Although it is almost impossible to distinguish newly stung fruit 
from external appearances, it becomes very easy after a few days when 
the infested apples become gnarly and ill:shapen, as shown in Fig. 1, a. 
PSYCHOLOGY. 
Professor Moll on Hypnotism.!—This work is a general résumé 
of what is known of hypnotism. The exposition by Prof. Moll covers 
most of the ground in an adequate manner, and is therefore well 
adapted for the instruction of the general reader. The author holds 
that suggestion is the efficient cause of the phenomena, and therefore 
regards the subject primarily as a’ branch of psychology, rather than of 
Physiology. He states that most persons of healthy mental organiza- 
tion can be hypnotized, and that susceptibility, except in extreme cases, 
1s not a mark of mental weakness. Persons of the nervous tempera- 
ment are most susceptible, and idiots and insane persons can be 
hypnotized in a small proportion of cases only. Susceptibility is not 
confined to any race or nation, so far as known. The statements of the 
numerous investigators are subjected to rigid and rational criticism, and 
nothing is accepted or rejected without adequate evidence. The ‘author 
pursues a judicial course in this respect, and refuses his assent to whole- 
Sale and uncritical scepticism, as well as to excessive credulity. Phy- 
siological explanations are frequently held in reserve as not proven, 
whatever degree of probability may attach to them. 
The abundance of well-established facts now recorded in the litera- 
_ ture of hypnotism has placed the subject within the domain of exact 
___ Hypnotism; by Albert Moll. The Contemporary Science Series, London : Walter 
.  Seott, New York: Scribner and Welford. 8vo. Edited by Havelock Ellis, 1890. 
