710 
KHYNCHOTA. 
Nepim:. 
Abdomen with a long (retractile) process ; antennce three-jointed ; fore¬ 
legs inserted on disk of anterior margin of prosternum. 
Among insects found in shallow fresh water, the “Water Scorpions’ 5 
are at once recognisable. They are flattened insects of dingy colour, the 
body elongate with nearly parallel sides ; 
the anterior legs are very conspicuous, 
being raptorial in something the same 
way as those of a mantis. The antennse 
are short and concealed; the rostrum is 
short and powerful; the eyes are well 
developed; the hemelytra cover the body 
and wings, and there are two long apical 
filaments which serve as a tube for con¬ 
ducting air under the hemelytra and so 
to the spiracles. These insects are found 
in water, which they rarely leave until 
migration to a fresh locality becomes 
necessary. They are believed to be wholly 
predaceous on other aquatic insects. None 
are known to have been reared in India, 
and but little is known of their habits 
anywhere. Eggs are said to be laid in 
aquatic plants and floating stems, and are 
provided with a number of filaments at 
one end (2 in Ranatra, 7 in Nepa), to facilitate respiration. 
The eggs of a species of Laccotrephes have been found in the leaf of 
Nelumbium speciosum ; they are about 2 m.m. long, cylindrical, with one 
end rounded, the other end truncate ; the rim of the truncate end bears 
long straight spines, set radially at right angles to the long axis of the 
egg ; there are 14 in some eggs, 15 in others. The spines measure nearly 
2 m.m. in length. These eggs are placed through the leaf, so that only 
the spines and flat end appear above, while the egg projects below into 
the water ; the spines hold the egg, lying flat on the upper surface of the 
leaf. On hatching, the egg breaks from the disc and spines, and the 
nymph emerges through the wide opening into the water direct. The 
Fig. 48*2.— Laccotrephes 
MACULATUS. X 2. 
