THE FROG -HOPPERS OR SPITTLE INSECTS 



(Family Cercopidce.) 



This is a rather large family comprising mostly rather small 

 insects, many of which are known as "frog-hoppers" or "spittle 

 insects." The antennas are placed between the eyes, there are 

 only two ocelli and the thorax is not strangely modified as with 

 the Membracidae. Few insects excite more interest among 

 moderately observant people than the true spittle insects which 

 belong to the subfamily Aphrophorinae. They are small, rather 

 slender, brown, day-yellow or grayish species, and after hatching 

 from the egg live in little masses of froth resembling spittle on 

 the stems of plants and trees, frequently on 

 grasses and weeds. In some parts of the 

 south, according to Uhler, the negroes thrnk 

 that horse-flies are developed from these froth 

 specks. When abundant they may do con- 

 siderable damage to pasture-lands. Philcvnits 

 spumarius and P. lineatus are said by Fernald 

 to be common on grass in Massachusetts. 

 The former is abundant in gardens in England 

 and was probably introduced from England Fig. 136.— Monecphorj 

 into this country. ^}?'l^J< ^f'T 



•^ U. S. Deft. AgT.J 



The eggs are laid in the stems of plants 

 in the autumn and hatch in the spring. It was formerly thought 

 that the spittle that soon surrounds the young insect was excreted 

 from the anus, but Professor E. S. Morse has recently shown that 

 only a clear liquid containing no bubbles is thus exuded and that 

 the air-bubbles are brought in by a constant thrashing about of 

 the anal end of the body, bringing in air which is retained as bub- 

 bles by the viscid quality of the liquid. There are anal append- 

 ages which are probably branchial m function, according to Morse. 



It is supposed that the purpose of the frothy mass is to pro- 

 tect the soft-bodied immature insects from their natural enemies 



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