INSECT VARIETY. 241 



directed posteriorly. This orifice (e) having- no lips, stands con- 

 stantly open. In Hetr odes pupa the hinder edge of the prothorax 

 has interiorly a lunate notch, whereby these openings are exposed. 

 The fundibular air-tnbes give out no branches in the thorax, but 

 serve as an adit to two tracheal pipes which enter the fore-legs, 

 where they part with some ramifications. At the femoral tibial 

 joint these become somewhat constricted, but almost immediately 

 afterwards dilate and form an elongate bladder exactly at the 

 place where the external clefts in the fore tibiae are found. 

 Beneath this they ramify and disperse. 



In that subdivision of the Leaf Crickets placed first by 

 Burmeister, the tibia is dilated superiorly with an ovate opening 

 at either side, closed by a membrane [meinbrana iympayiica) 

 (Plate II., Fig. B, iii). The drumskin consists of two parts, 

 namely, an elastic silvery membrane, with an anterior lunate 

 notch, and a black and brown oval chitineous disc situated in this 

 notch. In another section there is present on either fore tibia 

 a double capsule, one covering either drumskin (Plate II., 

 Fig. A, a) ; and in some species these prolongations of the 

 integument arch themselves strongly outwards, forming two 

 capacious cavities with oval openings anteriorly; but in others 

 these capsules are not so remote from the drumskins, and the 

 cavities are less capacious, presenting only two small clefts as 

 entries. 



Von Siebold states the internal construction of the tym- 

 panal organs may be determined in large Leaf Crickets when in 

 a fresh condition, by detaching the capsules with a knife, and 

 cleaving the tibia right and left, so as to raise its anterior 

 walls. Dr. Vitis Graber, more recently, has recommended 

 placing a leg in alcohol for a year, bleaching it with potash, and 

 if needs be, applying a drop or so of acid, a method possibly 

 economising labour in a necessarily difficult dissection. The 

 successful performance of either operation reveals that the 

 elongate tracheal bladder (Fig. C, Plate II.) aforementioned 

 occupies at this place almost the entire capacity of the tibia, 

 only allowing the muscles, nerves, and sinews intended for the 

 inferior part of the legs to pass posteriorly. It presents four 

 superficies — an anterior narrower surface, with a longitudinal 

 boat-shaped excavation; a hinder broad and arched one; and 



