36 BRITISH CICADA.. 



PARASITES OF THE TETTIGIDiE. 



Professor Pritchard tells us, with a good deal of 

 truth, that a large part of our pleasure connected with 

 exact knowledge, consists in the bye-paths (parerga) 

 which run more or less collaterally with our main 

 investigMtions. Early writers occasionally introduced 

 into their more special and grave matter paragraphs 

 which they called "Excursus." The kind-hearted 

 veteran zoologist, William Yarrell, expressed to the 

 author the belief that the interest taken by the 

 general public in his scientific works was in great 

 measure due to the introduction of collateral matter, 

 perhaps not strictly in sequence with his diagnoses of 

 species. 



Playfulness and clearness of style is not what the 

 present author lays any claim to ; and probably he 

 may, after all, fail therefore to clothe, what some may 

 think, the bare bones of science, m an alluring garb. 

 Still, under such an excuse, the present chapter on 

 Parasitism connected with the Cicadae is introduced to 

 the reader, though not in strict sequence with the 

 diagnoses. 



Like other insects, the Tettigidse are liable to the 

 attacks of parasites, both vegetable and animal ; but 

 only a few species up to the present time have been 

 specifically noted. 



In this Monograph some brief and general account 

 of their occurrence and habits may be expected, as 

 these pests — from the insect point of view — must have 

 some important bearings on the economy of their 

 hosts, and check their undue multiplication. 



Kearsley, as far back as the year 1802, published a 

 short notice of a singular fungoid grow^th on one of 



