THE ENTOMOLOGIST. 109 



hue. In 1844 raigratorius was abundant in S. Russia, and 

 in 1845, 1846 and 1847 it occurred in N. Germany, in 

 Belgium and in Sweden. According to De Selys' opinion, 

 raigratorius is a species or form peculiar to Tartary or 

 S. Russia, and only appears in W. Europe as an accidental 

 visitor, and may be reproductive there for a year or two 

 under the influence of favourable circumstances. De Selys 

 has received a specimen from Egypt, and Brunner considers 

 that migratorioides of Reiche and Fairmaire (found in Abys- 

 sinia and in Java) is an extreme form of raigratorius. The 

 fore wings of migratorioides are of a deeper brown, with the 

 markings effaced ; the hind legs appear to De Selys to be 

 longer and with more slender tibiae. Cinerascens is not 

 erratic in Belgium ; it is reproductive there every year, 

 though very local. It is also a truly indigenous species in 

 S. France, in Spain and in Portugal. 



In the variety obscurior (the type) the colouring is very 

 deep, varied with brown and with blackish on the head, the 

 thorax and the femora ; the hind tibiae are bright carmine- 

 red ; the markings of the fore wings are blackish and 

 approximate. This variety often occurs in Belgium. 



The name virescens may be given to the specimens where 

 a pale green is dominant on the head and on the femora, 

 and where the two black stripes of the prothorax are strongly 

 marked ; the red of the hind tibiae is a little paler, and the 

 fore wings are less dark. This variety also occurs in 

 Belgium, but is there a little darker than in S. Europe, 

 where it is represented by females of very large size, and 

 where there is a sub-variety dilutior, in which the markings 

 of the fore wings are almost obliterated. 



The name fuscescens may be given to another variety, 

 which has been found at Biarritz and in Portugal. It 

 resembles the S. European virescens by its great size and by 

 the markings of the fore wings, but the hind tibiae are pale 

 rose-colour, or of a yellowish hue, which is hardly tinged 

 with flesh-colour, and the body is pale brown instead of 

 greenish. This variety has not been observed in Belgium. 



In conclusion, De Selys remarks that the genus Acridiura 

 is represented in Europe by A. tataricum, and that the 

 locusts which devastated Algeria in 1864, 1865 and in 1866, 

 were A. peregrinum, and they proceeded from the Great 



