VIII MEMBRACIDAE CERCOPIDAE 577 



habits and life-histories. We have onlj two species of the family 

 iu Britain, and these do not afford any ground for supposing that 

 there are any peculiarities in their lives at all commensurate 

 with the oddness of the Insect's structures. Belt has recorded 

 the fact tliat in Nicaragua the larvae of certain Homoptera were 

 assiduously attended by ants for the sake of a sweet juice 

 excreted by the Inigs, but it is by no means clear that these larvae 

 were really those of Membracidae. In North America Ceresa 

 huhal'us and C. taurina place their eggs in an extremely neat 

 manner in the woody twigs of trees. The young have but little 

 resemblance to the adults, the yreat thoracic hood beina- al)sent, 

 while on the back there is on each segment a pair of long, sulj- 

 erect processes having fringed, or minutely spiny, margins.^ 



Fam. 4. Cercopidae. — Ocelli two {occasionally absent) i)laced 

 on the vertex; antennae i^laced hetween the eyes. Thorax not 

 2)eculiarly formed. — In the characteristic forms of this family 

 the front of the vertex bears a suture, touched on each side 

 by one at right angles to it, or converging to it so as to form a 

 triangle or a sort of embrasure ; tlie hind tibiae have only one to 

 three strong spines. The Cercopidae are much less extraordinary 

 than many of the previously considered families. But some of 

 them have the habit of secreting a large quantity of fluid ; and 

 when in the immature stages, certain of them have the art of 

 emitting the liquid in the form of bubbles which accumulate 

 round the Insect and conceal it. These accumulations of fluid 

 are called cuckoo-spits or frog-spits ; and the perfect Insects are 

 known as frog-hoppers, their powder of leaping being very great. 

 The most abundant of the frog -hoppers in our gardens is 

 Philaenus spumarius, a little Insect of about a quarter of an inch 

 long, obscurely coloured, with more or less definite pale spots; 

 it is so variable in colour that it has received scores of names. 

 Some of the Insects do not use their fluid in this manner, but 

 eject it in the form of drops, and sometimes cast them to a con- 

 siderable distance. The phenomena known as weeping-trees are 

 due to Cercopidae ; some of the species make such copious exuda- 

 tions of this kind that the drops have been compared to a shower 

 of rain. In Madagascar it is said that Ptyelus gov.doti exudes 

 so much fluid that five or six dozen larvae would about fill a 



^ Riley, P. enf. Soc. IVashington, iii. 1895, p. 88. For the 3-ounger stages of 

 Membracis foliata, see Tijdschr. Ent. (2) iv. 1869, pi. viii. 



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