REVIEWS. 311 
history of Aletia xylina, Say. (? argillacea, Hibn.), much further 
“in many directions, especially in its practical application. That 
the insect is worthy of a special report on account of its 
destructiveness is abundantly evidenced by the statistics given 
in Chapter I., where we read that ‘‘ the average annual loss may 
safely be put down at about 15,000,000 dols. for all the cotton 
States for the fourteen years following the war”; ina year of 
bad attack this loss has been doubled. 
The natural history, chronology, geographical distribution, 
parasites, and anatomy of this destructive Noctua are fully 
treated of in the first five chapters ; then follows an instructive 
account of the general features of the cotton belt by Professor 
Kugene A. Smith. Chapter VII. treats of the terrestrial and 
meteorological influences affecting the worm, and contains much 
useful local information. Many instances of erroneous opinions 
as to hybernation being firmly held by intelligent planters are 
given (pp. 16—22), and from experience in this country can well 
be believed. 
Chapter VIII. gives a full and well-illustrated account of the 
natural enemies, which are particularly numerous considering 
that not a single true parasite of Aletta had been recorded by 
name when the special investigation began; now we know of 
one parasite being bred from the egg, six from the larva, and five 
from the pupa. The account of a Cynipid (Hexaplasta zigzag, 
Riley) being a parasite of the dipterous Phora aleti@ is interesting 
and unusual. 
The next two hundred pages are devoted to different preventive 
measures, remedies and methods of destruction, some of which 
are very ingenious and doubtless well capable of further extension, 
but any wide application of others would appear futile or im- 
possible ; still it is well that all should be mentioned, for, as we 
are told by Dr. Riley in his preface, ‘‘ he has also endeavoured 
to bear constantly in mind that the chief object which Congress 
had in ordering the investigation was a practical one, and that 
whatever purely entomological knowledge was acquired, however 
interesting to the naturalist, was of less moment, unless it had 
some bearing on this practical phase of the subject.” So it 
should be, and so doubtless the large amounts voted by Congress 
will be considered to have been well spent: as far as we can see 
the work has certainly been thoroughly done and it has been 
