314 STATES OF INSECTS. 



state. Some, like several species of Ephemera', live only 

 a few hours ; some never even see the sun a : others, as 

 flies, moths, and butterflies, and indeed the majority of 

 insects, a few days or weeks ; and a comparatively small 

 number, such as some of the larger Coleoptera, Ottho- 

 ptera, &c, six, nine, twelve, or fifteen months — a period 

 beyond which the life of perfect insects rarely extends. 

 Some, however, certainly enjoy a longer existence in the 

 perfect state. Mr. Baker kept one of the darkling beetles 

 (Blaps Mortisaga) alive under a glass upwards of three 

 years. The rose-beetle (Cetonia aurata), Rosel informs 

 us he fed with fruit and moist white bread for as long a 

 period 5 . Esper kept our most common water-beetle 

 (Dytiseus marginalis) in water in a large glass vessel, 

 feeding it with meat, for three years and a half c . With 

 regard to the Arachnida, from the very slow growth of 

 Scorpio europtzus, Rosel suspects that it must live two 

 or three years ; and Audebert is stated to have kept a 

 spider for several d . In this respect insects follow a law 

 very different from that which obtains amongst verte-> 

 brate animals. In these the duration of their life is in 

 proportion to the term of their growth : those which at- 

 tain to maturity the latest, in almost every case living the 

 longest. In insects, on the contrary, we often meet with 

 the very reverse of this rule. Thus the larva of the great 



a Vol. 1. 283. h II. i. 6. 



c Clairville Ent. Helvet. ii. 214 — . I have seen it asserted in some 

 popular work on Natural History, (the title of which I do not recol- 

 lect,) that Mantis religiosa has been known to live ten years ; and a 

 flea, when fed and taken care of, six. But this is so contrary to expe- 

 rience in other cases, that the statement seems quite incredible. 



d Rosel III. 379. N. Diet. d'Hist. Nat. ii. 285. 



