Descriptions of Indian Acrididee. 489 
many other Locustine, such as species of Gdipoda, Mio- 
scirtus wagneri, Er., etc., among which forms with yellow 
wings and those with rose or sanguineous wings occur 
together. In the British Museum collections there are 
series of Morphacris from Uganda and other African 
localities taken at the same place and on the same day, 
amongst which not only the two known colour-forms (with 
red and with yellow wings) are represented, but an in- 
termediate one which has the disc of the hind wings orange, 
also occurs. This latter form has not yet been described, 
and I propose here to call it ab. aurantiaca, nov., its only 
difference from other forms being the orange-red coloration 
of the wings; as the type I designate one male from Kaig, 
Sudan, 27. 1°. 1904 (C. Singer). 
This difference in wing-coloration seems to be influenced 
by climatic conditions, and in dry localities the form with 
red wings (typical form) prevails, as in South Africa, while 
in West Africa, India, and Ceylon it is eutirely replaced by 
the yellow-winged form (ab. sulcata, Thunbg.); there are 
no records, as yet, of the red-wiftiged form from the latter 
localities. 
Specimens in the Pusa collection all belong to ab. sulcata, 
Thunbg.; they have been taken in Nainpur, Central Pro- 
vinces, iii. 1907; and Jalalpur, Surat, Bombay, on sugar- 
cane, 28. v. 1904. 
26. Locusta migratoria, L. 
One specimen without precise locality. 
The figure and description of Locusta danica, L., in 
Kirby’s book (Fauna Br. Ind. p. 176, fig. 104) undoubtedly 
represents L. migratoria, though the danica form is also not 
uncommon in India. 
27. Acrotylus humbertianus, Sauss. 
Pusa, on lentils, 19. ii. 1907; Chapra, Bengal; Keitni, 
Central Provinces, ii. 1907; Shevaroys, Madras, 4000’, on 
coffee, 24. viii. 1907; Bulsar, Bombay, sand-dunes, 16. v. 
1904. 
The habitus of this species is rather inconstant, and it is 
possible to distinguish two or three forms, which are, how- 
ever, connected by intermediate ones ; the speciniens from 
Pusa are especially slender. It is possible that examination 
of larger series will give grounds for dividing the species 
into geographical forms, but my material is not sufficient 
for this purpose, 
