MOTIONS OF INSECTS. 323 



variegata, has curious involuted suckers on its feet. 

 The strepsipterous genera Stylops and Xenos* are re- 

 markable for the vesicles of membrane that cover the 

 underside of their tarsi, which, though flaccid in old 

 specimens, appear to be inflated in the living animal or 

 those that are recent ft . It is not improbable that these 

 vesicles, which are large and hairy, may act in some de- 

 gree as suckers, and assist it in climbing. 



The insects of the Orthoptera order are, many of 

 them, remarkable for two kinds of appendages con- 

 nected with my present subject, being furnished both 

 with suckers and cushions. The former are concavo- 

 convex processes, varying in shape in different species 

 being sometimes orbicular, sometimes ovate or oblong, 

 and often wedge-shaped which terminate the tarsus 

 between the claw, one on each foot. They are of a hard 

 substance, and seem capable of free motion. In some 

 instances b , another minute cavity is discoverable at the 

 base of the concave part, similar to that in Cimbex lutea c . 

 The latter, the foot-cushions, are usually convex appen- 

 dages, of an oblong form, and often, though not always, 

 divided in the middle by a very deep longitudinal furrow, 

 attached to the underside of the tarsal joints. Sir E. 

 Home is of opinion that the object of these foot-cushions 

 is to take off the jar, when the body of the animal is 

 suddenly brought from a state of motion to a state of 

 rest d . This may very likely be one of their uses, but 

 there are several circumstances which militate against 

 its being the only one. By their elasticity they probably 



Kirby in Linn. Trans, xi. 10(>. t. viii./. 13. . 

 b I observed this in the hind legs of a variety ofLocusta migratoria. 

 Philos. Trans. 1816. /. xix./. 5. d Ibid. p. 325. 



Y 2 



