Chap. X. 
NEUROPTERA. 
361 
blue, and black; but as throughout the Order the 
two sexes rarely differ much in colour, it is doubtful 
whether they owe these bright tints to sexual selection. 
Conspicuous colours may be of use to these insects 
as a protection, on the principle to be explained in the 
next chapter, by giving notice to their enemies that 
they are unpalatable. Thus it has been observed 44 
that an Indian brightly-coloured locust was invariably 
rejected when offered to birds and lizards. Some cases, 
however, of sexual differences in colour in this Order 
are known. The male of an American cricket 45 is de- 
scribed as being as white as ivory, whilst the female 
varies from almost white to greenish-yellow or dusky. 
Mr. Walsh informs me that the adult male of Spectrum 
femoratum (one of the Phasmidse) “ is of a shining 
“brownish-yellow colour; the adult female being of 
“ a dull, opaque, cinereous-brown ; the young of both 
“ sexes being green.” Lastly, I may mention that the 
male of one curious kind of cricket 46 is furnished with 
44 a long membranous appendage, which falls over the 
a face like a veil ; ” but whether this serves as an orna- 
ment is not known. 
Order, Neuroptera . — Little need here be said, except 
in regard to colour. In the Ephemeridse the sexes 
often differ slightly in their obscure tints ; 47 but it is 
not probable that the males are thus rendered attrac- 
tive to the females. The Libellulidse or dragon-flies 
are ornamented with splendid green, blue, yellow, and 
44 Mr. Ch. Horne, in 6 Proc. Ent. Soc.’ May 3, 1869, p. xii. 
45 The Oecanthus nivalis. Harris, 4 Insects of New England/ 1812, 
p. 124. 
46 Platyblemnus : Westwood, 4 Modern. Class.’ vol. i. p. 447. 
47 B. D. Walsh, the Pseudo-nenroptera of Illinois, in 4 Proc. Ent. Soc. 
of Philadelphia/ 1862, p. 361. 
