132 LLOYD'S NATURAL HISTORY. 



Spilosoma urtica (Esper), or S. papyratia (Marsham), though 

 of equally wide general distribution with the last, is a rarity in 

 England, though still found occasionally in marshy localities, 

 where its larva feeds on water-plants. It may be known by 

 having only one or two black dots on the fore-wings. 



GENUS SPILARCTIA. 



Spilarctia, Butler, Cist. Ent. ii. p. 39 (1875); id. 111. Lepid. 

 Heter. Brit. Mus. iii. p. 6 (1879) ; Moore, Lepid. Ceylon, 

 iii. p. 71 (1882). 



This genus principally differs from Spilosoma in the greater 

 distance between the emission of the two lowest median ner- 

 vules of the fore-wings, the longer and more deeply fringed 

 tegulae, or shoulder-lappets, and the generally longer palpi of 

 the species associated under it. (Butler.) 



This is a considerably larger genus than Spilosoma^ number- 

 ing about fifty species, but it is not represented in Africa or 

 America. We have one British species. 



I may take this opportunity of emphasising the reply to an 

 objection frequently made against modern entomologists, that 

 they make -a separate genus for almost every species. A cen- 

 tury ago, when only a few hundred insects were known, it was 

 easy to classify them under one or two genera; but now 

 the species are reckoned literally by hundreds of thousands. 

 In the present instance, a single British species, which it would 

 not be necessary, as a British species, to separate generically 

 from its nearest allies, is our sole representative of a group 

 numbering fifty closely-allied species, and the establishment 

 of genera on more minute characters becomes a necessity. In 

 dealing with the insects of the world, it is necessary to treat 

 them in a manner which would be unnecessary, if not actually 

 reprehensible, in discussing a small local fauna only. 



