522 Mr. G. Lewis' supplementary note on the 



An instance to show my meaning in colour and form 

 may be given in Pterosticlius picimanus, Pedius incequalis, 

 and AcUenium Jmmile, which live in the crevices of clay 

 banks and become piceous, which is a slight indication 

 of a turn towards pellucidity, as they never run in the 

 sun ; and they are all flat to enable them to pass into 

 chinks. Pedius incequalis can escape Pterosticlius by 

 going into the smaller cracks, and the Achenium avoids 

 both by passing into the smallest crannies. The flattened 

 form originates in the common benefit to each while in- 

 habiting crevices, and colour follows from the nature of 

 their habitat. The Pedius is not necessarily piceous 

 because its allies in the South of Europe, which run in 

 the sun, are coppery or metallic. Another case may be 

 selected of form only. Lehia and Drypta are both trun- 

 catipennes ; the first sits on foliage, and continually flies 

 either for pleasure or to escape an enemy, and the 

 shortened wing-case assists this movement. I have seen 

 Driipta in great profusion ; overtaken by a sudden flood, 

 it will run up a stem of grass or reed to take to flight, 

 and it is in this genus again, we see the truncate elytron, 

 and the use of it. The necessity or benefit of quick 

 flight shortens the elytra very commonly in Coleoptera. 

 The shortened wing-case in the Staphylinidie is different 

 to that in Lehia, and arises apparently in another way 

 (see 'Ent. Mo. Mag.,' 1881, p. 138; and 1882, p. 213). 

 Instances such as the above can be multiplied without 

 end, but there is a very striking one in a Curculio and a 

 Staphylinus. Balaninus buries its rostrum in a nut, and 

 the antennae up to the elbow go with it. In this position 

 the remaining joints play about the eye and fulfil their 

 purpose there. When Cryptohium feeds the head and 

 mandibles are thrust into the object they delight in, a 

 decaying worm, or anything else, and the long basal 

 joint brings the small joints of the antennae behind the 

 eye. The common origin of the long joint here is, 

 I believe, the dimness of sight in both animals, which 

 necessitates the feelers being brought back. The varied 

 species of Balaninus show what immediate modifications 

 the genus can go to. The long joint of the antennae in 

 the two genera shows that like wants, arising in like 

 conditions, give like form. In Rhynchites and Apoderus 

 the head is not inserted into their food-plants, nor are 

 the antennae elbowed. 



Perhaps it will be said that these are interesting facts 



