COLEOPTERA 5,3 



island: this majorit\' includes 10 of the most distinct forms: and of eight of these we 

 have series of over six specimens. The iS specimens of the large and distinct 

 A. kanaiciisis. and the 17 specimens of the well-marked .-/. piDictatits, are all from 

 Kauai. On the other hand, some species, such as A. minor, appear to he undoubtedl)- 

 found in more than one island. In some cases, all the specimens of a fair-sized series 

 are from a single locality, or a very few localities. These obscure forms have not at 

 present been at all exhaustively collected. 



As stated above, the species do not appear very closely allied to those of other 

 parts of the world : while the various groups of them have each, with scarcel)- an excep- 

 tion, close inter-relations among themselves. In one or two cases, certain forms seem 

 to be represented by two or more closely allied species in different islands : thus 

 A. punctatus (known only from Kauai) is close to A. kitkiiiae (Oahu), and A. sailptus 

 (jMolokai) is represented in Kauai by A. niakaivcliac. In respect of a single character 

 (the nature of the diverging \entral striae), A. sitbrotniidus stands away from all other 

 species without visible scutellum : agreeing in that one resjject with A. insularis. On 

 the whole it appears probable that most, at any rate, are precinctive. Should this 

 prove to be so, and should some s])ecies prove to be confined to single islands, these 

 phenomena will onl)' he in accordance with what is known of the general nature of the 

 Hawaiian fauna. 



No general statements as to the variability can be made from a study of the 

 present material. The specimens of the larger series show very little variation, except 

 in some cases clear differences which are very probably sexual (see under A. makatvcliac, 

 and footnote p. 522). It is possible that a tew new species described from single 

 individuals will prove to be onl\- varieties ot other species, but the great majority are 

 quite distinct from one another. 



Certain structural features of these Hawaiian species must be noticed. Ue Marseul 

 in giving the characters of the genus writes' : " Front sans strie ni depression trans- 

 versale qui le distingue de lepistome." In a few of the Hawaiian species, however, a 

 distinct transverse suture just in front of the antennae is present : in most there is no 

 trace of it : when present, it is mentioned in each case. Lower surface of the head 

 behind the labium with only a single median suture. The prothorax has always a very 

 fine marginal stria along the lateral and front borders ; as this is hard to see, and offers 

 no distinguishing characters, no other mention is made of it. The stria along the 

 deflexed ventral marginal part of every elytron also a[)pears to offer no characters. One 

 or two oblique striae may be present near the shoulder of the elytron : the)- may be 

 distinct furrows, vague, almost imperceptible, often cjuite ah.sent : ver)- variable in the 

 specimens of a single species, and of no use in distinguishing species. W'hether the)' 

 are present or not, the sculpture in the part of the elytron near the shoulder is nearly 

 always different to that on the rest of the disc (PI. X\'. fig. 7). The area at the 



' .Ann. Soc. ent. l-'rance (3) iv. 1856, [i. 596. 



66—2 



