ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
465 
only of much interest, but of much value ; for it will be remembered 
that Mr. Blackwall informed Charles Darwin that he had never observed 
and was not inclined to think a quarrel probable. The drawings from 
life, and the further descriptions given by this indefatigable student of 
the living spiders, are of the utmost practical value. The same may be said 
of “ the love dances of Saltigrades,” as displays to attract females, and 
many similar observations are not only valuable confirmations of the 
studies of others, but are indications to field naturalists of new and 
important directions for observation. 
On maternal industry and instincts we have another group of 
chapters, full of evident work and suggestiveness. The weaving of the 
silken sac within which the eggs are deposited, and its subsequent dis- 
posal so as to secure the greatest protection for its vital contents from 
the exigencies of weather and the assaults of enemies, are presented with 
a detail and sympathetic insight, accompanied by beautiful graphic 
portrayal, which gives unique value to the work ; and at the same time 
attention is called to the work of others, so that a practical account 
of our present knowledge on the subject is fully given. 
On the early life and distribution of species, and on the “ balloon- 
ing ” habits of spiders, there are many things of much interest said, as 
there are on the senses of spiders and the relation which the senses 
bear to habit, dealing with the minute structure of their eyes, and 
discussing in detail specialities in work, such as cocooning and snare- 
building in the dark, and the general “ night habits ” of the Spider ; 
the colour of eyes, the cases of atrophy in these, their sensitiveness to 
light and the limit of their vision when they are normal, and the con- 
dition of cave spiders, are all carefully considered and illustrated. So 
also are the sense of smell, of hearing, and the delicacy of touch ; in 
like manner an account is given of the nature and purpose of stridulation 
in some spiders. 
This careful study of the nature and habits of aranean life also 
involves a discussion of colour and the colour sense in spiders, which 
we are inclined to believe would have been more broad and deep had 
their manifest sexual influence been more readily admitted ; but no 
student of spiders can study it without much profit. The influence of 
mimicry amongst spiders is carefully considered and illustrated in all 
its relations ; the influence of the enemies of spiders on their habits, 
and the disguises of death feigned by them are presented and illustrated 
in a manner which, if this book were accessible to the multitude, would 
secure for it a larger number of readers than are now likely to peruse 
its pages. 
The book has yet to be completed by a third volume. Certainly this 
second one, with its five beautiful chromolithographic plates, surpasses 
the promises of its author, and when the whole book is complete we can 
but hope that its popularity, combined with its accuracy and originality, 
may make a new edition possible, which will at once relieve the author 
of the cares and, we fear, uncompensated cost of the present mode of 
publishing. 
External Characters of Mites*— Dr. L. Karpelles describes the 
bristles, the extremities of the appendages, and the jaws of some mites. 
* Verh. K. K. Zool.-Bot. Geeell., xli. (1891) pp. 300-6 (6 pis.). 
