These Insects are amongst the most curious of natural objects. They are frequently of large size, some attaining 9 inches in length (Fig. 162, _Palophus centaurus_, one-half natural length). Their variety of form could scarcely be surpassed; their resemblance to products of the vegetable kingdom is frequently very great: some of the more linear species (Fig. 148, _Lonchodes nematodes_) look like sticks or stems of grass; some have a moss-like appearance, while others resemble pieces of lichen-covered bark. The members of the tribe Phylliides are leaf-like. A certain number of other Phasmids are covered with strong spines, like thorns (Fig. 149). The plant-like appearance is greatest in the female sex. When there is a difference between the two sexes as to the organs of flight, these are more fully developed in the male. {261}[Illustration: FIG. 148.—_Lonchodes nematodes._ Malay Archipelago. (After Westwood.)] The antennae are usually many-jointed, but the number of joints varies from 8 to more than 100; the head is exserted; the eyes are more or less prominent; ocelli are present in some cases. The prothorax is always small, and it is a remarkable fact that it undergoes but little elongation even in those species that are most linear and elongate in form (see Fig. 148, _Lonchodes nematodes_), and that have the meso- and metathoraces extremely long; it is very simple in structure, consisting apparently merely of a dorsal and of a sternal plate, nearly the whole of the side being occupied by the large space in which the coxae are inserted; the edges of the pronotum are not free. The mesothorax is frequently six times as long as the prothorax, though in the leaf-like and a few other forms it does not possess this great extension; still it is always of large size relatively to the other two thoracic segments. This is peculiar inasmuch as in other groups where the mesothorax is relatively large there are powerful mesothoracic wings; whereas the Phasmidae are remarkable for the obsolescence of the mesothoracic alar appendages. The middle legs and the tegmina or elytra, when present, are attached only to the posterior part of the mesothorax; the notum and the sternum are separated by two narrow slips on each side, the epimeron and episternum. The metathorax is formed like the mesothorax, except that the posterior part of the dorsal surface is considered to consist of the first ventral segment consolidated with the posterior part of the metanotum, the two being distinct enough in the winged forms. The hind body or abdomen is elongated except in the Phylliides; it consists of ten dorsal plates; the first frequently looks like a portion of the metanotum, and is treated as really such by Westwood, who describes the abdomen as consisting of nine segments. The flat apical appendages are attached behind the tenth dorsal plate. The ventral plates are similar to the dorsal in arrangement, except that in the female the