INTRODUCTION cxli 



mountains of Maui and Hawaii above the forest line, or on the edges of the region of 

 large timber. Both species are found beneath stones, B. rupicola almost entirely so, 

 but B. mcendiarius on Hawaii, on the edge of the forest-belt, also occurs low down 

 under bark of Koa trees, sometimes even beneath the level of the soil. Both are 

 common beetles in suitable localities. Barytietis sharpi, differing from the preceding in 

 its well-developed wings, is of far more arboreal habits and may be obtained high up in 

 trees from beneath bark, usually of Acacia koa ; but it is not restricted to that tree. 

 Very rarely it is seen at large during the daytime, ovipositing in the chinks of the Koa 

 trees. Colpodiscus contains two species, one of which is common to Maui and Hawaii, 

 and is often extremely abundant, flying in numbers to light at night. On Hawaii it is 

 usually found amongst dead leaves or fallen stems of tree-ferns, or beneath logs, but in 

 the lao valley it was found beneath stones or shingle on the banks of the stream, where 

 C. lahainensis also occurs. Once we found a specimen devouring an Oniscus, a creature 

 usually avoided by Carabidae, so that where it abounds under stones, ground-beetles 

 are usually absent. Prodisenochus terebratus is found only on Haleakala, Maui, beneath 

 or in decaying logs and appears to be rare. It is sometimes in company with 

 Atrachycnemis, but is I think rarer than the latter. Apteromesus maciilatus is restricted 

 to Kauai, where it is common locally. Mysticomenus with two closely allied species is 

 only known on Oahu. AI. niysticus is said to occur beneath stones, but M. tibialis is 

 common under bark in both mountain ranges. 



The genus Colpocacciis, with six described species, contains some of the commonest 

 Hawaiian Carabids, and most of the species are excessively closely allied, so that 

 I suspect the number is liable to be reduced. They all are attracted by light at night 

 in the forest region, to which they are restricted. They are remarkable for the in- 

 constancy of their habits, not one of the forms being restricted to a special habitat. 

 They may be found beneath stones, under or in logs, under bark of trees, in the stems 

 of tree-ferns or amongst the dead fronds, in decaying vegetable matter on the ground, 

 at the bases of leaves of Freycinetia, etc. and in other situations. Colonies even of 

 hundreds of individuals are sometimes found together, and sometimes other rarer 

 Carabidae are found mixed in these colonies. At night they may be seen at large on 

 trees, or running about on the margins of mountain streams or on the ground beneath 

 the forest trees. The fifteen species of Atelothrns are mostly found on the neighbouring 

 intermediate islands of Maui, Molokai and Lanai, only one having been found on each 

 of the islands Hawaii and Kauai, and that from the former island is of somewhat 

 doubtful status (as to whether it is not a sport of Mesothriscus or Metromenus) and that 

 from the latter is an aberrant form. Though none are recorded from Oahu, I have for 

 some years known two remarkably distinct species from this island. Some of the 

 species of Atelothrns, e.g. the very abundant A. erro, are not constant in their habits, 

 since they are found both under stones, etc. on the ground and beneath bark of trees at 

 a considerable height from the ground. Others like A. platynoides and transiens. 



