HARDWICKE'S SC lEN CE-GOS S IP. 



53 



several contributors of this journal, I fancy some 

 little interest has been excited to further investiga- 

 tions of these organs ; for that reason I feel induced 

 to give a brief sketch of another order of Homo- 

 ptera, section Trissiene, genus Aphrophora, species 

 Aphrophora spumaria. 



fig. 43. Suctoricil tube, lancets, &c., seen from beneath, 

 X 120. 



This insect, the " Frog-hopper," will probably be 

 of more general interest, for, although so common, 

 it is little known. Many persons no doubt have seen 

 the frothy secretion upon the branches and leaves 

 of shrubs during the summer months, and probably 

 know that it is commonly designated cuckoo-spit, 

 and this, perhaps, is the only idea of many concern- 

 ing it. This secretion is effected on the larva leaving 

 the egg. It covers itself with a froth, fixing its ros- 

 trum into the cellular tissue of the plant on which 

 it is fixed ; it draws up a sufficient quantity of sap to 

 cover itself, pouring out a secretion from the organs 

 placed at the terminal portion of the abdomen (this 

 secretion is the spit) ; but a more careful observer 

 will find, upon breaking it up, a small green larva, 

 with yellow eyes ; the insect thus protected passes 

 through its larva of different stages until it arrives 

 at maturity. 



Upon subjecting the larva to the microscopic 

 glass, the suctorial tube, lancets, &c., will be seen 

 (fig. 43) composed of the labrum, which forms a 

 jointed sheath for the slender trestle-like mandibles 

 and maxillae, and also a canal for the passage of 

 the juices upon which the insects live. 



In its mature state it is a dull, stone-bodied, incon- 

 spicuous insect with awl-like antennae (fig. 44), from 

 the last joint of which springs a trestle appendage. 

 Posterior legs adapted for springing, the extremity 



of tibia and tarsus being terminated with tooth- 

 shaped spines (fig. 45). 



The elytra when subjected to microscopical ex- 

 amination will be found very beautiful. The ground- 

 work is seen to be made up of cellular tissue or 



Fig. 41, Head and Awl-like antenna of Froghopper. 



oval spots, arranged in irregular transverse rows, 

 ihese spots are of uniform dimensions,* consisting 

 of a centre, surrounded by a white circle, each spot 

 bemg divided from its fellow by a space nearly equal 



Fig. 45. Posterior leg and terminal claw. 



to its own diameter; and, when viewed as an 

 opaque object, stand out in relief. The females are 

 furnished with a singular and beautiful apparatus 

 (fig. 4C), by which they are enabled to form excava- 

 tions or grooves in the twigs or leaves of plants, for 

 the purpose of depositing their eggs (which are 

 large and few in number). It is analogous to 

 the instrument possessed by the Tenthredo or Saw- 

 flies. On the under surface of the terminal segment 

 of the abdomen, nearly at the extreme point, are seen 

 a pair of valves or palpi, which form the sheath for 

 the auger or boring instni,meut. Upon a casual 

 view this auger appears like a denticulated arrow- 

 headed spear, but on a more minute examination it 

 is seen that what appears at first sight a single 

 instrument, is made up of four distinct portions, 

 two deeply indented blades set back to back, and a 

 middle support, in which they slide : the remaining 

 two have their outer edges smooth, but the inner 

 are cut into the most regular minute serrations. 

 These facts are probably known to many ; still there 

 may be a few to whom this brief sketch may be in- 



* This is more discernible when the elytra is mounted on 



balsam. 



