Coleo liter a from tlie Ilawaiian Islands. 81 



The impression left on my mind with regard to these 

 insects may be thus summed up : — 



1. In Proterhinus and Aglycyderes we are probably 

 dealing with very primitive Coleoptera, such, in fact, as 

 existed before the present great development of the highly- 

 differentiated families of the order had occurred. 



2. That Ayly cyder es and Protcrldnus may be treated 

 as one family, to be placed at the commencement of the 

 famihes of Rhyncophora. 



8. That the distinctions between the two forms are of 

 such a nature that they may be justly treated as repre- 

 senting two ultimate divisions of one fixmily : i. e., the two 

 forms remain ununited through a considerable number of 

 repeated and progressively more itn])ortant syntheses, till 

 the synthesis of family value is reached, when they unite 

 to form the family Ayly cy derides. 



It may not be amiss here to remark tliat the few species 

 constituting this primitive family are all members of 

 insular fauna? : Aylyci/dcres setlfer being confined to the 

 Canary Islands ; A. IVollastoni to New Zealand; and the 

 species of Proterldnus to the Sandwich Islands. 



HYDROPHILID^E. 



Omichus (new name). 



Omicrus brevipes, n. sp. Minutus, latus, subrotundatus, 

 parum convexus, subtus rufescens, opacus, supra nigro- 

 piceus, nitidus, nudus, capite anterius rufescente, pedibus 

 rufis, antennis palpisque testaceis, illis clava fusca ; capite 

 thoraceque fere Ifevigatis, hoc margine laterali tenuissimo; 

 elytris parum subtiliter hand dense punctatis, stria sutu- 

 rali tantum posterius impressa, versus latera parum dis- 

 tincte seriatim punctatis. Long. 1;^ mm.; lat. 1 mm. 



This little insect has perhaps at first sight more the 

 aspect of a Cyclonotum than of any other Hydrophilid ; 

 it is among the smallest of the family, only attaining the 

 size of a moderate Lirnnebius : the very short, and rather 

 stout middle and hinder tarsi, the joints of which are 

 compressed and adjusted to one another, but are not, I 

 believe, fitted for swimming, arc characteristic. 



Oahu ; Avidely distribnted, but not connnon. No. 236 



TllANS. ENT. SOC. 1879. — rAllT I. (aPR.) G 



