57° 
NATURE 

London Entomological and Natural History Society, 
Ig14-15. Original observations, made by the author 
himself, add materially to the value of this contribu- 
tion. Originally, it is assumed, developed as a pro- 
tective device against enemies—the light-emitting 
qualities being associated with, or perhaps the cause 
nauseating properties—luminosity has become 
primarily a secondary sexual character. This much is 
attested by the response which can be obtained by 
experiment from the use of small electric bulbs. 
These experiments conclusively show that each species 
has its own characteristic method’ of exhibiting its 
light, and that an individual from any one species 
will, as a rule, only respond to, or evoke an answer- 
ing flash from, a member of the opposite sex of that 
species. Some species, moreover, respond more readily 
to artificial flashes than others. Some will even 
answer the flash of a match. Luminosity in some 
cases, however, seems to play a directly utilitarian 
part, as in the case of the fly Thyreophora cynophila, 
which is said to be nocturnal in habit, and to feed on 
dead bodies by the light of its phosphorescent head. 
Finally, the author discusses numerous instances of 
pathological luminosity due to luminous bacteria, as in 
the cases of certain midges and crustacea. 
of, 
STUDENTs of genetics, no less than systematists, will 
welcome the “Review of the South American 
Sciuride,” by Mr. J. A. Allen, which appears in the 
Bulletin of the American Museum of Natural History, 
vol. xxxiv., 1915. In discussing the value of size as 
a “group character,’’ the author remarks that closely 
related forms present a small average range of varia- 
tion, inter se, and a very wide range of individual 
variation. Specificity is determined, not by individuals, 
but by groups of individuals. In attempting to dis- 
cover tangible differences in the form of the skull and 
the character of the teeth in American squirrels, with 
a view to their use as the basis of generic or sub- 
generic divisions, some surprises were met with in 
respect to the variability of such features in specimens 
of the same species from the same locality. The form 
and the details of the crown pattern of the last pre- 
molar and the last molar were found to be extremely 
unstable features. The author also makes some ex- 
tremely interesting observations on colour variations 
and the evolution of new types of coloration. 
From the Department of Agriculture, Ceylon, have 
been received Bulletins Nos. 12, 13, and 14, dealing 
with Hevea tapping results at the experiment station, 
Peradeniya, the tapping of an old Hevea tree at 
Heneratgoda, and manuring of cacao at Peradeniya 
respectively. The old Hevea tree is apparently one of 
the original trees sent out from Kew in 1876, and its 
girth in August last was 117 in. at 3 feet from the 
ground. The tree has been tapped with short intervals 
over a period of 4 years 9 months, and the total yield 
of rubber has been 392 Ib. 7 oz. 
Tue Polyporacez of Wisconsin form the subject of 
Bulletin xxxiii. of the Wisconsin Geological and 
Natural History Survey. This great family of fungi, 
which has been worked out by Mr. J. T. Neuman, is 
represented in Wisconsin by a great number of species, 
NO. 2386, VOL. 95] 

[JULY 22, 1915 

and Cyclomyces is the only genus unrecorded. The 
bulletin consists of 148 pages of descriptive text with 
twenty-five plates of figures, which should enable the 
fungi to be easily identified. As many of the Poly-_ 
poracez are serious timber-destroying fungi the book 
should prove of value in the United States. Of the 
destructive forms, Polyporus abietinus, P. pergamenus, 
growing on maple, willow, oak, etc., Trametes pini 
and Fomes ungulatus, cause the greatest damage to 
timber trees. 
We have received a copy of a new publication 
entitled “Egyptian Agricultural Products,’ published 
by the Ministry of Agriculture, Egypt, dealing with 
Sorghum vulgare, Pers., the great millet and its 
varieties, and also with S. halepense, Pers. The 
account, No. ra, 1915, has been compiled by Mr. G. C. 
Dudgeon, consulting agriculturist to the Ministry of 
Agriculture, Egypt. Botanical descriptions of the 
types and the varieties are given, followed by details 
of the history of the great millet in Egypt, and full 
cultural details. It seems probable that S. halepense, 
which is indigenous in Egypt, is the plant from 
which S. vulgare and its numerous varieties have been 
evolved. The uses of the grain and the leaves are also 
dealt with, and the question of the poisonous char- 
acter of the young leaves is discussed. When grown 
under dry conditions the young leaves appear to be 
more poisonous than when grown moist, but as the 
toxic properties are destroyed by heat the precaution 
is always taken of exposing young leaves to the sun 
for some time before feeding them to cattle. When 
mature the leaves afford a safe cattle food. 
Tue first volume of the Agricultural Statistics of 
India (1912-13) is particularly valuable on account of 
the new features, which include charts, summary 
tables, and a comprehensive introductory report. The 
charts indicate considerable progress since rg01, and 
the increased acreage devoted to cultivation has been 
accompanied by an improved yield in the crops. The 
decline in the acreage devoted to indigo and opium 
continues; and the minor fluctuations in area under 
the other crops are shown to be largely due to rainfall 
deficiencies. In a comparative statement it is shown 
that India has under rice more than eleven times the 
area of the paddy fields of Japan, that India is the 
third country in the world in regard to acreage under 
wheat, since there isunder that cereal three times the 
Canadian area and three-fifths that of the United 
States, that India has the largest acreage under maize 
outside the United States, and that the area under 
cotton in India is three-fifths that of the United States 
and twelve times that of Egypt. This issue may be 
regarded as the first of a new series of annual reports. 
An important contribution to the geography of 
Canada has been made by Mr. J. B. Tyrrell, of the 
Geological Survey, in a paper reprinted from the 
Transactions of the Royal Canadian Institute, Toronto, 
entitled ‘‘Algonquian Indian Names of Places in 
Northern Canada."’ In the course of fifteen years’ 
service in that region Mr. Tyrrell made extensive 
inquiries from natives. regarding the original names 
of the chief physical features in the Cree and Ojibway 
cna A nn 

