320 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
a. Insecta. 
Insects Injurious to Crops.* — Mr. C. Whitehead, a technical adviser 
to the Intelligence Branch of the Board of Agriculture, gives detailed 
notices of various insects (and fungi) noted in 1892 as attacking the 
crops of the farm, orchard, or garden. A new departure, made with 
the object of facilitating the identification of the pest, is the addition of 
carefully coloured plates, reproduced from sketches by Mr. Whitehead. 
One of the most severe ravages of a not very notable year were the 
attacks of the mustard-beetle — Phsedon betulse, the raspberry-moth — 
Lampronia rubiella, and the red spider — Tetranychus telarius , which was 
most troublesome in spring to gooseberry bushes, and, later in the year, 
to damson, plum, and peach trees; in the last few years red spiders 
have increased enormously, and have attacked various crops. Apples 
have been attacked by the Apple-blossom Weevil — Anthonomus pom ovum, 
and by the Codlin Moth — Carpocapsa pomonana. The most general 
visitation was that of the Mangel fly — Anthomyia betse ; and very great 
injury was done by the minute larvae of the Frit Fly. This report 
should interest a number of agriculturists and entomologists. 
Hybridism among Insects.f — Dr. M. Standfuss states that the 
pairing or the attempted pairing of different species has been observed 
in almost all orders of insects, but hybrid offspring are known only in 
the case of Lepidoptera, e. g. Saturnia spihi Schiff and S. pavonia L. 
The hybrids between a male of sp. A and a female of sp. B are not the 
same as the hybrids between a male of sp. B and a female of sp. A. 
The hybrid usually shows characteristics of both parents, but is not a 
precise intermediate form. “ The male reproductive element determines 
the external features of the hybrid much more essentially than does the 
female,” or, to put it more accurately, the external features of the hybrid 
are much more like those of the paternal species than those of the 
maternal species. Most of the hybrids are sterile. 
Effects of Temperature in the Pupal Staged— Mr. F. Merrifield 
has made a number of experiments on the effects of temperature in the 
pupal stage on the colouring of Pieris napi , Vanessa atalanta , Chryso- 
phanus pMoeas, and Ephyra punctaria. With regard to the first of these, 
experiments prove that some, but not all of the characteristic colouring 
depends, not on the particular emergence, i. e. summer or spring, to 
which the insect, when entering on the pupal stage, belongs, but on the 
temperature to which the individual pupa is exposed. In C. pJiloeas it 
appears that the principal effects on colour, &c., are produced not by 
long exposure to severe cold, but by exposure, during the period when 
the active part of the pupal stages has begun, to (1) great heat, producing 
duskiness or (2) moderate cold, producing vividness and intensity of 
colouring, smallness of spots, and great enlargement of the copper band 
on the hind wings. The difference, therefore, in appearance between 
C. phloeas from Southern Europe and C. plilceas from England is not 
necessarily to be attributed to the existence of races of different colouring, 
* ‘ Report on Insects and Fungi Injurious to Crops,’ London. Board of Agriculture, 
1893, GO pp., 10 pis. t MT. Schweiz. Entomol. Gesell., viii. (1893) pp. 386-96. 
X Trans. Entomol. Soc. Lond., 1893, pp. 55-67 (1 pi.). 
