INSECT VARIETY. 223 



pleheja, though less sharp and distinct. The three species, both 

 as regards their general anatomy, as in respect to the structure of 

 their organs and habits are thus widely difPerentiated. They 

 are all tolerably plentiful in Southern Europe in the height of 

 summer, Hmmtocles appearing in June and the other two in^July, 

 but only Pleheja extends as far north as Fontainebleau, where it 

 IS rare. The smaller Continental cicada; also sing ; for the little 

 C. argenfata, Ohv., of Sardinia is described as mounting the 

 lower oak-bushes and ringing out a clear sharp and metallic 

 '^ Tick ! tick ! tick ! '' repeated fifteen times, and this often with 

 great rapidity. Orni is made a plaything by children, who tickle 

 it with a straw, when it begins to sing in a laughable fashion. 



While the music of the Cicadse presents traits in common with 

 the plaint of the Hymenoptera and whining of Diptera, the 

 specialisation of the productive organs produces phenomena and 

 determines the biology in uniformity with stridulation. Thus 

 the incentives of love and rivalry are evinced by the males con- 

 secutively responding to the fitful notes of a congener, as by the 

 sexes, even diverse as to species, being so induced to congregate 

 on one spot or on the same bough, a feature peculiarly striking 

 m the tropical zone, where it has often intruded on the notice of 

 travellers. -On my march with the army of the Indus,^^ says 

 a writer in the Journal of the Asiatic Society of Bengal, * 

 "from Kandahar towards Cabool, I observed a remarkable con- 

 gregation of Cieadae, composed of more than one species. The 

 branches of the tamarisk were covered with them, as hardly to 

 be able to distinguish a particle of green, and their noise all day 

 was unceasing; the jewassee bushes being at the same time 

 covered with the empty scales of the pupa-. Our tents and tent- 

 ropes as soon as pitched were covered by these insects, in fact, 

 everything looked yellow. The only enemies they appeared to 

 have were some large dragon-flies, which pounced upon them 

 and carried ofE what appeared to be double their own weight." 

 This circumstance was witnessed fifty miles from Kandahar. 



South Europe produces only about sixteen species of Oicadse, 

 but m countries where they are more numerous and of larger 

 size, as Australia, their noise is deafening. Dr. G. Bennett f has 



* Aslac. Soc. of Bengal Jour., Vol. IX., p. 441 (1840). 

 t G. Bennett, "Wanderings in New South Wales." 



