422 



INSECTS MUM AD. 



the word glaberrima, which signifies "very smooth," is given to 

 it on account of the glossy and polished surface of the body. 



Many systematic entomologists have formed the insects of 

 which the Thynnus Australia is an example into a separate 

 family under the name of Thynuidrc. 



Why this name should he given to the insect, or indeed to 

 any insect at all, is more than I can understand, inasmuch as 

 the word Thynnus signifies the tunny fish, and ought never to 

 have been foisted upon an insect. In this genus the male and 

 female are so distinct that they have been described as two 



cw 



£ 



- - -*-w w 



Fig. 218.— Thynnus Australia Mak 



(Black and yellow.) 



distinct species — the one as Thynnus, and the other as Myrme- 

 coda. Indeed, had it not been for an opportune discovery by 

 Mr. Lewis, the identity of the two insects would not even have 

 been suspected. It is rather curious that another so-called 

 Myrmecoda has turned out to be nothing but the female of a 

 Scotoma. 



The genus Thynnus appears to be exclusively Australian, and 

 all of them have a very wasp-like look about them. The present 

 species almost exactly resembles our common hornet, except 

 that the dark portions are black instead of deep chestnut. They 

 are all parasitic insects, feeding on the subterranean lame and 



