of the Mole-cricket. 427 



Casti?ig of the skhi. — The following are the only observa- 

 tions I have had an opportunity of making as to this point of 

 the history of the mole-cricket. In the process of moulting, 

 the skin of the abdomen appears to split longitudinally down the 

 middle of the upper part; and the skin of the thorax separates 

 in a similar direction; but the skin of the head only separates 

 partially in that direction, and then splits between the stem- 

 mata, in a direction towards each of the antennae ; so that the 

 line of separation somewhat resembles the lambdoidal suture 

 of the human skull. 



The corneas of the eyes are cast with the rest of the skin, 

 as in the case of the snake ; but they lose their transparency, 

 and become of a grayish white colour. 



Even the covering of the claws is cast. 



The newly exposed surface of the whole body is covered 

 with the same kind of down as that which covei'ed the prece- 

 ding skin ; except in the case of the long bristly hairs of the 

 caudal antennae, which apparently are produced afterwards. 

 The colour of the body immediately after the casting of the 

 skin is j'ellowish white, and it remains of that colour for a few 

 hours: it afterwards gradually darkens. 



T/ie orga7i of sound. — I have very little doubt that the pecu- 

 liar sound which is chai'acteristic of this insect is produced by 

 the wings ; for I have observed in several individuals in their 

 perfect state, that, when irritated, they will separate their upper 

 wings by a brisk motion laterally from each other ; and that 

 upon their being suddenl}-^ brought back to their natural posi- 

 tion, a sound is at the same moment produced, resembling that 

 which I have heard the insect spontaneously produce during 

 the season of summer : but I could not fix the power of pro- 

 ducing this sound to either sex exclusively. 



There is a peculiar organ, forming a part of the common in- 

 teguments of the abdomen, and situated between the fourth 

 and fifth stigma on each side ; the anterior portion of which 

 consists of a tense membrane, like fine parchment, of a semi- 

 lunar form : this organ from its individual character might be 

 supposed to contribute towards the production of the sound, 

 but it is found in the female as well as in the male ; and its 

 supposed use is not justified by the presence of any internal 

 mechanism. 



In two or three instances I have perceived the internal and 

 upper surface of the second abdominal segment, answering to 

 what is generally called the third thoracic segment, furnished 

 with two oblong concave laminae, terminating in free rounded 

 edges, which are probably elastic ; but I feel by no means cer- 

 taui that these are exclusively cliaracteristic of the male, though 

 3 H 2 I cer- 



