466 



Marvels of Insect Life. 



plate with two or three strong and hard folds. Just behind it on the second segment 

 is a prominent area whose surface is marked by very hne, raised lines. Both sexes 

 have these arrangements, but in the male they arc more highh' developed than in 

 the female. The thigh is rubbed over these sculptured plates, and the action results 

 in a loud note. It is believed that the male can produce two distinct notes, one 

 agreeing with that of the female, and one peculiar to its own sex. It is a very 

 sedentarv creature, and its colouring makes it appear like a clod of earth. When 

 molested it does not relv upon its full powers of locomotion for escape, but upon 

 its capacitv for making a noise which will alarm its enemy. 



The long-horned green grasshoppers^ produce their music by means of the 

 wing-covers alone, and as these onlv slightly overlap at their bases, the production 

 of a considerable volume of sound seems at first sight not to be expected. Yet 

 anyone who has heard one of these Insects giving expression to its joy, must admit 

 that the volume of sound produced is marvellous. We have kept our nati\'e green 

 grasshopper - as a pet, feeding it upon flies, and in the evenings it sang with notes 

 that resounded through the house. In this famih' the ears are placed in the front 

 legs, a little below the knee. De Geer pointed out long ago that an eye-like spot in 

 the right wing-cover of the male was probably connected with the powerful note 



of this species. This area consists of 

 a transparent film " resembling a 

 little mirror or piece of talc, of the 

 tension of a drum. This membrane is 

 surrounded bv a strong and pro- 

 minent nervure, and is concealed 

 under the fold of the left wing-cover, 

 which has also several prominent 

 nervures answering to the margin of 

 the film. There is every reason to 

 believe that the brisk movement with which the grasshopper rubs these nervures 

 against each other produces a vibration in the membrane augmenting the sound." 



The katydids, celebrated Insect musicians, which are described in a separate 

 article, belong to the family of long-horned green grasshoppers. 



We have already mentioned that the too-familiar house-cricket has, in the male, 

 a musical file on the under side of each wing-cover ; and this is a character 

 which will be found throughout the family to which it belongs. In the 

 mole-cricket^ the musical organs are smaller and simpler than those of the 

 house-cricket, and the note produced by them is a dull, jarring note \\hich has 

 been compared to that of the nightjar. 



M ason- Wasps. 



The mason-bees, described in a separate article, have their counterpart among 

 the wasps. Though there is naturally some resemblance in their methods, there 

 are also some differences. The species with the best title to the name of mason- 

 wasp is a graceful little Insect* about half an inch long with a black body banded 

 with yellow. For a building site it chooses the slope of a sandbank where the 



^ Locustiche. - Locusta viridissima. ^ (irvllus gryllotalpa. ' ( )dyneru.s spiiiipes. 



Wing-cover of a Long-horned Grasshopper. 



The darker portion is that which overlaps or is overlapped by its fellow 

 f wing-cover. The clear space is the drum whose vibrations give resonance 

 to the sounds produced by the adjacent iil;-. 



