TRACHEATA 337 
and fond of heat. The eggs are laid in a capsule or ootheca, 
which is variously shaped in the different species; it is often 
carried about by the female protruding between the terminal 
segments of the abdomen for some days before it is deposited. 
II. GRESSORIA include two very remarkable families of 
Insects, the Mantidae and the Phasmidae. Their legs are 
adapted for walking. 
The Mantidae have their anterior pair of legs modified to 
form predatory organs. The toothed tibia can be folded down 
against the femur, as the blade of a pocket-knife into the 
handle. This subchelate appendage is used in capturing 
other insects or spiders for food. The prothorax, which bears 
these enlarged appendages, is very much elongated. The 
abdomen is elongated and oval. The commonest colour of these 
Insects is green. The eggs are laid in regular clumps on 
sticks or stones. Mantis religiosa is found in South Europe ; 
the devotional attitude in which it sits, with the anterior legs 
raised, has obtained for it the name of the praying insect ; 
many legends and superstitions centre around it. 
The Phasmidae are mostly tropical insects of large size which’ 
feed on leaves. ‘They are slow in their movements, and escape 
observation by their very extraordinary resemblance to various 
natural objects amongst which they live. The genus Phylliwm 
of the East Indies mimics various forms of leaves, the veins on 
the wings resembling the venation of the leaf, and in some 
cases the legs bear flattened leaf-like expansions which in- 
crease the resemblance; others have holes in their wings and 
a dried appearance which simulates that of a tattered, withered 
leaf. The genus Phasma includes many species of an elongated 
shape which closely resemble dried twigs; one species attains 
the length of 12 inches. Ceroxylus laceratus is covered 
with tufts of processes which give it the appearance of a mossy 
twig. The whole family affords a very striking example of 
protective resemblance. 
III. SaLratortaA.—This division includes all those forms 
which have the legs modified for jumping, such as the grass- 
hopper, locusts, and crickets. It may be divided into three 
families : 
1. Acridiidae or Grasshoppers.—The body is compressed, 
22 
