78 BRITISH cicad.t:. 



be found in the forms of the thorax and the scutelhim. 

 The males of the Cercopidae are smaller, but brighter 

 in colour than the females, which observation is in 

 accordance with Mr. Bates's remarks on this sex of 

 insects generally. 



The singular mode adopted by the larvae for conceal- 

 ment has been long known. Grermar notes it in the 

 generic name he gave to theF ^miijAphrophora, from a^pos 

 and (pspu (froth-bearing). The habit consists in forcing 

 numerous bubbles of air, which are discharged from the 

 tail-end, through a tenacious liquid secreted by a special 

 organ. A drawing of this organ may be found in my Plate 

 B, figs. 8 and 9. The soft-bodied larva3 live pretty secure 

 from their enemies under this spume, and compara- 

 tively they are unaffected by the droughts of summer. 

 A single mass of froth may contain more than one 

 individual ; and also within it several exuvia, or casts 

 of the previous stages of growth, may be seen com- 

 plete, even to the joints of the antennaB and to the 

 long set^ of the proboscis. The froth is most abun- 

 dant in moist weather, and then it will fall in drops 

 from the food-plants, but in dry weather it concentrates 

 up to a certain point, and then evaporation would seem 

 to cease. The fluid can be drawn between the fingers 

 into viscid threads ; yet when evaporated on a slip of 

 glass, it merely leaves behind a gummy mass, which 

 shows no particular structure under the microscope. 

 Alcohol throws down a flocculent precipitate from 

 aqueous solutions. 



The larvae when plunged into water become restless, 

 and emit a stream of air-bubbles, after which they will 

 remain quiescent, as if dead, for more than an hour. 

 If taken out of the water they speedily revive. The 

 tenacity of life is remarkable in these young forms, for 

 they will exist for a considerable time when put into 

 petroleum spirit ; and even when dissected the viscera, 

 including the organ which secretes this spume, will 

 show a curious peristaltic movement after an hour's 

 submergence. What may we augur from these visceral 



