108 THE ENTOxMOLOGIST. 



P. MIGRATORIUS. 



1. Male and female of equal size. 



2. Prothorax straightened laterally in the middle ; dorsal 



keel comparatively low. 



3. The two black longitudinal spots of the prothorax 



effaced. 



4. The black markings of the fore wings forming narrow 



lines. 



5. Inhabits Eastern Europe, the region of the Black Sea, 



Himalaya region, and Manilla. 



P. CINEEASCENS. 



1. Male much smaller than the female. 



2. Prothorax of equal breadth along the whole length ; 



dorsal keel comparatively high. 



3. The two black longitudinal spots of the prothorax 



always very distinct. 



4. Fore wings marked with rather large black spots. 



5. Inhabits S.W.Europe, the Mediterranean region, Greece, 



Syria, Algeria, Madeira, Canary Isles, Bengal, Ma- 

 nilla, Australia and New Zealand. 

 De Selys adds that in cinerascens the two black spots of 

 the prothorax are only very distinct in the variety which 

 he names virescens, and that in the sub-variety dilutior irom 

 the South of Europe the dark markings of the fore wings are 

 nearly effaced. He remarks that according to Brunner the 

 colour of the hind legs is variable in both species. Never- 

 theless he has observed that in cinerascens the hind tibiae 

 are almost always red (or flesh-colour in the wdiV. fuscescens), 

 but never bluish, while in migratorius the hind tibisB are 

 never red, but are most often blue, passing sometimes into 

 pale yellow, or slightly into flesh-colour. The hind part of 

 the prothorax generally forms, in cinerascens, a slightly 

 acute angle ; in migratorius, a right or slightly obtuse angle. 

 The two blackish stripes of the prothorax, in cinerascens, 

 are often continued as far as the eyes in the greenish speci- 

 mens from S. France and from Belgium (var. obscurior). 

 Generally, in the Belgian specimens, the head is marked 

 above with two dark parallel streaks, which are often seen in 

 the true migratorius ; and, on the contrary, the two lateral 

 black stripes are indistinct on account of the dark ground 



