88 



in addition to the vicinity of Vienna. In the latter district the author 

 remarks that whereas Anophelines were somewhat abundant in the 

 warm summer of 1911, their numbers were less in the cold, wet summer 

 of 1912 and especially 1913. Of the Wachau and the richly watered 

 Danube valley beneath it, the author's former experience holds good, 

 namely, that breeding places for Anopheles larvae are provided by 

 such shallow sheets of water as have escaped recent flooding and are 

 protected from the wind by plants on their banks ; but as a rule, only 

 species of Cidex occur. In warm, dry summers Anophelines would 

 probably be more frequent, but in any case the conditions are not 

 favourable to widespread malaria. The third district is around 

 Freistadt, in the east of Austrian Silesia, and abounds in Anopheles, 

 malaria being prevalent. One doctor stated that he alone had some 

 700 cases a year. On alighting at Chybi the author was surprised 

 at the numbers of mosquitos settled on the walls and ceilings in the 

 station. This was the case in every building. The country is of a 

 very marshy character, and though many fields have been reclaimed, 

 a considerable number of pools still remain. Human habitations 

 are numerous throughout the district and mosquitos occur abundantly 

 in them. In the other districts referred to above, the breeding places, 

 of Anopheles are far removed from dwellings and thus but few of them 

 are found indoors. Draining the marshland would cost too much, but 

 bv thoroughly destroying the vegetation around the pools they would 

 cease to be suitable breeding places. This would also be profitable 

 in another way, as these plants diminish the feeding capacity of these 

 ponds for fish. Houses should not be built near such water and the 

 people should be taught the danger attached to the presence of 

 mosquitos. The compilation of exact statistics is a necessary initial 

 step. 



GiRAULT (A. A.). Preliminary studies on the biology of the Bed-bug, 



Cimex lectularius, Line. — Jl. Econ. Biol., Londmi, ix, no. 1, March. 

 1914, pp. 25-45. 



The experiments described in the present paper are concerned with 

 the breeding of Cimex lectularius and its feeding habits. Different 

 pairs of males and females were kept, and the eggs laid were counted ; 

 in one case the female laid 190 eggs from 27th February to 24th June ; 

 the last thirteen laid were not fertile. In another case 139 eggs were 

 laid from 27th February to 12th May, all except five being fertile. 

 A third female laid 168 eggs between 22nd February and 15th May, 

 all being fertile except one. A fourth laid 130 eggs from 22nd February 

 to 11th May, all fertile. A fifth laid 109 eggs from 10th January to 

 15th February. Eggs laid on 1st February hatched on 10th February, 

 and the insects reached maturity on 18th March. Females of this 

 generation laid 86 eggs from 25th March to 11th May in one case, and 

 89 eggs from 27th March to 15th May in a second. Larvae of the third 

 generation hatched out on 20th April. The author showed experi- 

 mentally that this bug will feed readily upon mice, sparrows, moles and 

 guinea-pigs. Many individuals subsisted for some months on the 

 blood of the guinea-pigs and oviposition occurred. 



