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in ANIMAL LIFE IN THE TROPICAL FORESTS 287Mantidseusually called " praying insects," from their habit ofsitting with their long fore-feet held up as if in prayer arereally tigers among insects, lying in wait for their prey, whichthey seize with their powerful serrated fore-feet.They areusually so coloured as to resemble the foliage among whichthey live, and as they sit quite motionless, they are not easilyperceived.The Phasmidse are perfectly inoffensive leaf-eating insects ofvery varied forms some; being broad and leaf-like, while othersare long and cylindrical, so as to resemble sticks, whence theyare often called walking-stick insects. The imitative resemblanceof some of these insects to the plants on which theylive is marvellous. The true leaf-insects of the East, formingthe genus Phyllium, are the size of a moderate leaf, which theirlarge wing-covers and the dilated margins of the head, thorax,and legs cause them exactly to resemble. The veining of thewings and their green tint exactly correspond to that of theleaves of their food-plant ;and as they rest motionless duringthe day, only feeding at night, they the more easily escapedetection. In Java they are often kept alive on a branch ofthe guava tree and it is a common;thing for a stranger, whenasked to look at this curious insect, to inquire where it is, andon being told that it is close under his eyes, to maintain thatthere is no insect at all, but only a branch with green leaves.The larger wingless stick-insects are often eight inches toa foot long. They are abundant in the Moluccas ; hanging onthe shrubs that line the forest-paths ;and they resemble sticksso exactly, in colour, in the small rugosities of the bark, in theknots and small branches, imitated by the joints of the legswhich are either pressed close to the body, or stuck out atrandom, that it is absolutely impossible, by the eye alone, todistinguish the real dead twigs which fall down from the treesoverhead, from the living insects. The writer has often lookedat them in doubt, and has been obliged to use the sense oftouch to determine the point. Some are small and slenderlike the most delicate twigs ;others again have wings, and itis curious that these are often beautifully coloured, generallybright pink, sometimes yellow, and sometimes finely bandedwith black ;but when at rest the wings fold up so as to becompletely concealed under the narrow wing-covers, and the