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rhynchota. 
periods seen in Lepidoptera, Coleoptera and Hymenoptera. The nymph, 
as it comes from the egg, has much the same habits and structure as the 
adult and the changes at the separate moults are very small. The most 
noticeable change at the last moult, next to the assumption of functional 
wings, is the change in the position of odoriferous glands, one new pair 
becoming functional on the ventral surface of the thorax, in place of the 
two pairs on the dorsal surface of the abdomen. The final moult does 
not imply sexual maturity, but the development of the sexual organs 
continues for some time and a period considerably longer than the 
nymphal period may elapse before the sexual organs are really mature. 
There is thus no metamorphosis and though we may find, in the 
young nymph especially, habits and colouring which it loses in a later 
instar, the change is not an abrupt one. Details of the metamorphosis 
of few Heteroptera are known in India, but there is a certain amount on 
record and a good deal more not yet placed on record. There are prac¬ 
tical difficulties in observing the nymphal life, but these can be overcome 
in the case of plant-feeding species. 
Pentatomim:. 
Scutellum large. 
Pentatomid bugs are recognisable at sight by the large scutellum and 
the mouthparts, even where the resemblance to a beetle is noticeable ; 
beginners will certainly confuse them on superficial examination. They 
are insects of moderate size, from a quarter of an inch to over an inch in 
length, robustly built and with hard integument. Colours are of great 
variety, black, brown, grey and other sombre colours in a large number, 
green and shades of dull yellow in others, bright colours in a few only. 
The colour is often cryptic, in some apparently warning, and in the 
species which live in the soil is the sombre colouration characteristic of 
most insects in that situation. The form of the body is not modified for 
cryptic purposes and there are only occasionally spines, etc., on the 
integument which are adapted to this end, or which serve some obscure 
function, possibly in rendering the insect distasteful. 
The antennse are five or four-jointed, simple. The head is flattened, 
usually a little produced anteriorly, with small compound eyes and 
ocelli. The rostrum is straight, lying against the prosternum. The 
prothorax is well developed, accurately fitted to the mesosternum and 
