688 
NATURE 
[AUGUST I9, 1915 

Prionine, by F, C. Craighead. In the Journ. Agric. 
Research (vol. iv., No. 3) W. S. Pierce describes 
weevils of the genus Diaprepes, which injure sugar- 
cane in the West Indies, and gives details as to 
their variation and life-history. 
The gipsy moth (Porthetria dispar) imported from 
France into Massachusetts in 1869 continues to occupy 
the attention of American entomologists; Mr. A. F. 
Burgess describes the means adopted in the New 
England States for checking its ravages (Bull. U.S. 
Dept. Agric., 204). His account is iilustrated by an 
interesting set of maps showing the present range of 
the species in New England, and also of some of its 
natural enemies which have been imported from 
Europe, of which the large ground-beetle, Calosoma 
sycophanta, is the most formidable. Reference is also 
made to the strange ‘‘ wilt-disease’’ which at times 
fortunately becomes epidemic among the caterpillars. 
It has been made the subject of a special research by 
Mr. R. W. Glaser (Journ. Agric. Research, vol. iv., 
No. 2). He finds that the disease was not present in 
North America before 1900, and believes that its spread 
may be at least partly due to some of the introduced 
parasites. The causative micro-organism has not been 
demonstrated. 
The cabbage-fly (Phorbia or Chortophila brassicae) 
is one of our commonest and most destructive garden 
pests. Mr. J. T. Wadsworth has published (Journ. 
Econ. Biol., vol. x., No. 1) a valuable and interesting 
account of a rove-beetle, Aleochara bilineata, the larva 
of which eats its way into the puparium of the 
cabbage-fly, and feeds on the pupa. ‘Like some other 
beetle life-histories, this shows a tendency to hyper- 
metamorphosis, the newly-hatched Aleochara being of 
the campodeiform type normal to the family, while 
the later instars, in accordance with their parasitic 
habit, have shortened legs and swollen bodies, 
approaching the cruciform type. 
A contribution to our knowledge of the physiology 
of aquatic insects is due to Mr. S. K. Sen, who gives 
some observations on the respiration of Culicidz 
(Indian Journ. Med. Research, vol. ii., No. 3). The 
larva of Culex microannulatus consumes 1-1 cubic mm. 
of oxygen per hour, the pupa 1-9 cubic mm., and the 
imago 2-5 c.c.; the increased oxygen-hunger of the 
pupa as compared with the larva is noteworthy, and 
it was found that the pupa is more quicklv affected and 
killed by the want of oxygen. Systematic study of 
blood-sucking Diptera goes steadily on; the British 
species of Simulium are diagnosed by Mr. F. W. 
Edwards in the last number of the Bulletin of Entom. 
Research (vol. vi., part 1). This same number con- 
tains a report by Dr. W. A. Lamborn on the ‘“‘con- 
trol” of tsetse-flies (Glossina) in Nyasaland; a number 
of flies were caught by bird-lime spread on boards 
carried about by native boys, and digging-wasps are 
found to seize tsetses and carry them off. Hymeno- 
pterous parasites of the Chalcidoid group have been 
reared from Glossina puparia in northern Rhodesia, 
and these are described with excellent figures by Rev. 
Jas. Waterston, in the same number of the bulletin. 
Of slight importance from the economic point of 
view, the Odonata (dragonflies) are yet of great general 
interest to the student of insects. Mr. E. B. William- 
son has just published (Proc. U.S. Nat. Mus., vol. 
xlvili., pp. 601-38) some exceptionally valuable notes 
on Neo-tropical species belonging to the ‘‘ demoiselle ” 
(Agrionine) subfamily. The purely systematic entomo- 
logical paper is usually a weariness to any not a 
specialist who may attempt to read it, but this author 
enlivens his accounts of structural details of diagnostic 
value with descriptions of the habits and adaptations 
of the beautiful insects which he loves to observe when 
alive in the swamps and forests of Central America 
and the Antilles. (ea leh, C. 
NO. 2390, VOL. 95] 

THE NATURAL HISTORY. OF 
CORUNDUM.1 
lie the Summary report of the Geological Survey of 
Canada for 1896 Mr. W. F. Ferrier directed atten- 
tion to the occurrence of corundum crystals in the 
township of Carlow, Hastings County, Ontario, and 
to the probable economic importance of the discovery. 
This announcement led to the opening up of what has 
become the largest corundum mining industry in the 
world. In 1910 an important memoir by Adams and 
Barlow on the general geology of the district in which 
the corundum-deposits occur was published by the 
Geological Survey (Geology of the Haliburton and 
Bancroft Areas, Memoir No. 6), but the details as to 
these deposits were reserved for fuller treatment than 
was possible at that time. They are now given in the 
present volume, together with a general account of 
the occurrences of the mineral in other parts of the 
world. 
Apart altogether from their economic importance, 
the Canadian deposits are of considerable scientific 
interest as throwing light on one of the methods by 
which corundum has been naturally produced. They 
are usually associated with nepheline and other allxa- 
line syenites which occur at the junction of the great 
Laurentian granitic batholiths with the limestones of 
the Grenville series. Red alkaline syenites, rich in 
soda, together with their coarse-grained pegmatitic 
equivalents, are pre-eminently the corundum-bearing 
rocks throughout the district, although in one of the 
smaller areas the mineral occurs in anorthosites. The 
| richest rock is known as corundum-pegmatite, dykes 
of which may attain a width of 18 ft. and contain as 
much as 75 per cent. of corundum. Individual crystals 
weighing 30 lbs. have been obtained from this rock. 
In other rocks they are smaller in size, and often sink 
to microscopic dimensions. The colour usually varies 
from blue to white. No transparent varieties suitable 
for use as gems have as yet been found. 
In his classic researches carried out in Warsaw 
during the years 1891-96 and published in Tscher- 
mak’s Mineralogische und petrographische Mitthei- 
lungen for 1898, Morozewicz proved that felspathic 
magmas, especially those rich in soda, possessed the 
power of dissolving alumina, and that on cooling the 
excess of alumina over that required to form felspar 
crystallised out as corundum. The facts described in 
this memoir clearly prove that the Canadian corundum 
has crystallised out of a highly felspathic magma 
in accordance with the principles experimentally 
established by Morozewicz. The mineral is extracted 
from the rocks by blasting, hand-picking, crushing, 
and dressing by methods akin to those frequently 
used by miners. From material fed to the mills con- 
taining 103 per cent. of corundum a high-grade pro- 
duct consisting of from 90 to g5 per cent. is obtained. 
It is at present employed solely as an abrasive agent, 
although researches have been, and are still being, 
carried out to discover other uses. The value of the 
total amount placed on the market to the end of 1913 
is about 2,000,000 dollars, and there has been no 
appreciable falling off in the amount produced during 
recent years. Its principal rivals are carborundum 
and artificial corundum, known as alundum, both of 
which are produced at Niagara Falls. 
ANCIENT ARABIC METEOROLOGY.? 
AS what stage of intellectual development, pre- 
monitory signs of weather were first connected 
with coincident, but probably unrelated, phenomena, 
1 “*Corurdum: Its Occurrence, Distribution, Exploitation and Uses.” 
Ry Alfred Ernest Barlow, Department of Mines, Canada. Pp. 377+28 
plates and a geological man of Central Ontario. 
2‘*Some Arabic Weather Savings.” By Mohammad Bey Kasim. 
| BE from the Cairo Scientific Journal, Nos. 97 and 98. (Alexandria, 
1914. 


