COLEOPTERA 289 



Rhantus Lacordaire. 



Colymbetes pacifiais Boisduxal, \'oy. Astrolabe i. p. 50. 

 Rhantus pacifictis Sharp, Tr. Dublin Soc. (2) 11. {1S82), p. 607. 



When dealing with this species, 1. c, I stated that it varied so much that there 

 might be two species. I had then only two specimens, and even at present I have seen 

 only seven or eight ; perhaps the difference in the specimens may be chiefly sexual, for 

 the male appears to be considerably larger than the female. 



Hab. Kauai. — Oahu. — Lanai. — Molokai. — Maui. — Hawaii. — Probably all the 

 islands (Blackburn). 



§ 3. Bionomical notes. 



The following notes are in larger part gathered from correspondence that has been 

 carried on with Mr Perkins during the preparation of this paper. As the information 

 they give is of considerable interest I think it well to publish them. It will be seen that 

 notwithstanding the small variety of structure that exists in the Hawaiian Carabidae the 

 habits are singularly varied. In other words difterentiation of habits has been up to the 

 present greater than that of structure. This is quite in conformity with the views I have 

 briefly expressed on p. i 79. The doctrine, that differentiation of function precedes, on 

 the whole, that of structure, was expressed by Herbert Spencer many years ago. The 

 remark made on p. 291 by Mr Perkins as to Colpodiscus lucipetens is an exemplification 

 of the same idea. 



The quotation marks indicate the words of Mr Perkins. They were not intended 

 for publication, but, as I have already said, they appear to me to be ot so much 

 interest that I take the liberty of printing them. His remarks refer chiefly to species of 

 the Anchomenides, but we may hope that he will give us further information about 

 Pterostichides and Bembidiides on some future occasion. 



Blackbnrnia. p. 191. "Apparently found only under stones." 



Deropristus, p. 192. "Never under stones, only beneath wood or fern-trunks." 

 Mr Blackburn is said to have found the unique specimen of D. blaptoidcs under stones. 



Atrachyciiciuis\ p. 193. " Like Dcroprisins, never under stones." 



Pseudobroscus, p. 196. " Under stones. Certainly very rare ; everything has to 

 be exactly right as to position of rock, dampness, etc., for this insect." 



Anchoh'fflus, p. 195. The two species are terrestrial ; A. ckgans occurs under 

 logs ; gracilis under stones, Mr Perkins believes. 



Matma, p. 200. This is also terrestrial, living under stones. 



' On p. 19s I have expressed a doubt as to whether this genus is really found in the island of Hawaii. 

 Mr Perkins has now informed me that it is not. The home of A. kocbelei is W. Maui. 



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