182 THE CAUSES WHICH PROPAGATE 



perches, and each bit the head of the female wearing his 

 livery. 



On Plate III., Fig-. 8, are portrayed two males of the 

 larger green grasshopper thns engaged in a musical contest on a 

 grass-stem, and tracked by the larger female. In this country 

 none of this family seem in any way injurious, and if we accept 

 the green-coloured kinds, which as green leaves, seek dusky 

 shade and moisture, where, with other green insects, they 

 conserve their delicate charm, the relish of this family is want- 

 ing in an island with an equable temperature, for these are 

 pre-eminently lovers of Nature parched and dry, manoeuvring 

 their armies on plains scorched by summer stms, led on by the 

 chanticleer males quarrelling over the best pasture and winds of 

 heaven, 'Hhat return again according to their circuits.''^ 



=?5=^ 



, N ^ I J^TZ: 



3--*i— 5— 2-^ 



5i-.5E*^ 



SONG OF THE GRASSHOPPERS. 

 From Latuiois' " Ton utid Stimma^paraie der Insecten. 



GRYLLID^ (CEICKETS). 



In this dull-coloured subterranean group of Orthoptera, the 

 masculine charm that gathers together the locust legions to 

 devastate grassy plains, and flocks of leaf -crickets to defoliate 

 forest verdure, manifests itself as a social character, and the 

 rival music of the males and subjection of the females originates 

 associated burrows, where the sexes live solitary in angry neigh- 

 bourhood. By their music they also express perception o:^ 

 rivalry and love, with a general notion of fear communicated by 

 the auditory nerve, which finds musical expression. Thus the 

 males of the field-crickets are diurnal, stridulating in sunshine. 

 The music of the European kinds, G. camj^estris, melas, or si/lves- 

 fris, is a brisk " Cree-cree ! " loudest in the first. The sound 

 increases when the males are in proximity, and is mitigated 

 and broken by short sharp notes at equal intervals during the 

 presence of the female ; it ceases at the approach of an observer. 

 The rhythm of the nocturnal house-cricket varies in pitch, and 

 it has also an alarm-note, said to be understood by its kind. 

 Grijllotalpa and (Ecayitkus are musical towards evening. 



