CHAP. XI 



STICK-INSECTS 



261 



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, Zonchodes 

 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 inas- 

 much 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 append- 

 ages. 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 sur- 

 face 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 Fi 

 really such by Westwood, who describes the abdo- 

 men 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 eighth plate forms a sort of spoon-like 

 or gutter-like process to assist in carrying or depositing the eggs, and 

 that the two following segments are concealed by it, and are some- 

 times of more delicate texture. The legs vary greatly in the details of 



. 148. Loncho- 

 des nematodes. 

 Malay Archi- 

 pelago. (Alter 

 Westwood. ) 



