NoveMBER 29, 1918] 
stream, and with the aid of a large reading- 
glass attached to a pole, it was possible to see 
the feeding movements of the mouth-parts. 
Several observations were recorded later than 
this of specimens of Gerris remigis sucking 
the juices of these berries. Only on one other 
occasion was Gerris marginatus seen to use 
this fruit as food. The plant from which these 
fruits came is commonly known as the coral- 
berry or Indian currant, Symphoricarpos vul- 
garis. It is very common along the banks of 
the brook near Whiteheath. 
I have found that, during my observations of 
the food habits of water-striders in captivity, 
while confined in aquaria, both species men- 
tioned suck the juices of freshly killed Physa 
and Planorbis. They also feed on fresh beef, 
on the soft parts of banana fruit, and on the 
inner, softer parts of the skin. 
These observations seem.to add additional 
evidence to Hungerford’s'! contention that 
aquatic Hemiptera are neither entirely preda- 
cious, nor do they feed entirely upon insects. 
It is very likely that other observers could re- 
port further observations of the character that 
have been recorded here. 
C. F. Curtis Ritey 
Tue New York State CoLuEGE OF FoRESTRY, 
At Syracuse UNIVERSITY, 
Syracuse, New YorkE 
SCIENTIFIC BOOKS 
Wild Animals of North America: Intimate 
Studies of Big and Little Creatures of the 
Mammal Kingdom. By Epwarp W. NELson. 
Natural-Color Portraits from Paintings by 
Louis Agassiz Furrtes. Track Sketches by 
Ernest THompson Seton. Published by the 
National Geographic Society, Washington, 
D. C., U. S. A.; 8vo, pp. + 385-612, folded 
frontispiece, 108 colored illustrations on text 
paper (not plates), 85 halftone illustrations. 
[This is essentially a reprint of two articles 
which appeared in the WNationai Geo- 
graphic Magazine, for November, 1916, and 
May, 1918. The changes comprise repaging 
beyond page 472, the readjustment of the 
11 Loe. cit., pp. 336-337. 
SCIENCE 
547 
matter on pages 473-475, the replacement of 
a half-tone on page 475, the rectification of 
page references to illustrations to accord 
with the new paging where needed, and read- 
justment of the matter from page 571 on, 
so as to admit 32 new illustrations of foot- 
prints and the captions to these.] 
This is a work which meets to a gratifying 
degree the need for an essentially non-tech- 
nical treatise upon the natural history of the 
mammals of North America. No living person 
is better equipped to carry to a successful con- 
clusion such an undertaking than is its author. 
Nelson has contributed in the field of verte- 
brate zoology now for over forty years, to be 
explicit, beginning in July, 1876 (Bulletin 
Nuttall Ornithological Club, Vol. 1, p. 39). 
With a background of long experience in the 
field, and with further years of official con- 
nection with the United States Biological Sur- 
vey and its unique resources in mammalogy, 
he has made available a brochure of pleasing 
amplitude and satisfying authoritativeness. 
Between the colored pictures and the written 
sketches the public can gain from this con- 
tribution a better idea of our principal mam- 
mals than from any other available publica- 
tion. It should awaken a generally greater 
interest in our native mammals, and this will 
help build up a desire for the conservation of 
the harmless and useful species such as has 
resulted from the public education in relation 
to our bird life. On the other hand it is im- 
portant to be able to distinguish those mam- 
mals, chiefly of the order Rodentia, which are 
thoroughly inimical to human interests. Peo- 
ple at large must know how to cope with these 
enemies. It would seem that a full knowl- 
edge of the natural history of such animals is 
essential to determining the most successful 
means of controlling them and to applying 
these means properly to the varying conditions 
throughout the country. Nelson’s accounts of 
our injurious mammals are full of stimulative 
suggestions along these lines, and while the 
work as a whole can not be considered as an 
“economic” publication, its influence will go 
far to secure adequate popular consideration 
of these matters. 
