254 FAUNA HAWAIIENSIS 



Thus in Apterocis some of the species e.g. A. ephistenioides are quite regularly 

 convex, the prothorax being very closely adapted to and continuing the curve of the 

 elytra. In others, e.g. A. rufo-notatus, A. variegatiis, &c., the outline is not regularly 

 convex, but is interrupted at the point of contact of the elytra and prothora.x. Some of 

 the species of this latter group closely resemble A. ephistemoidcs in general appearance, 

 but others e.g. A. variegatus have a very coarse sculpture, and one {^A. hystrix) is 

 unique in the genus as being conspicuously clothed with erect hairs. We also notice 

 differences in the structure of the mesosternum in front of the coxae, and in A. varie- 

 gatus and probably in the allied A. omatipennis, the metasternum is less short than is 

 normal in the genus. 



Of the species assigned to Cis, C. pacificiis is the most commonplace and 

 greatly resembles European species, and will probably be found to be not indigenous. 

 It has some resemblance to C. breviformis but to no other species, and the latter also 

 has a very different appearance to the truly indigenous species, and I suspect may 

 prove to be also foreign. Another species C. alienus may also prove to have 

 been introduced. The remaining 26 species are all of peculiar facies, and exhibit 

 considerable variety of form and appearance, and must be considered as peculiar to the 

 islands. Cis violokaioisis (and probably C. kaleakalae, the unique example of which 

 could not be examined from this point) is wingless or nearly so, but we have not 

 separated it generically on that account, because the wings of another species, C. fallax, 

 are in a more or less rudimentary condition, and we are not even certain whether this 

 species is more than a variety of the normally full-winged C. signatus. Besides 

 these species, C. miiints and C. diviinuiivus appear to me to belong to the same 

 group, and will probably prove to have the wings either absent or rudimentary, 

 the abortion of the wings being accompanied, in most of the species at least, by a 

 shortening of the metasternum. In these characters it will be seen that the insects 

 above mentioned approach to the genus Apterocis, but they lack the oval and highly 

 convex form, which is so striking a feature of the latter. Nevertheless the complex 

 affinities between the Hawaiian species of Cis (excluding the doubtfully indigenous 

 forms) and Apterocis render it highly probable that the latter originated in the islands, 

 through forms somewhat similar to some of the species of Cis, which now inhabit 

 them. 



Some few of the species of Cis are found in large fungi growing e.xternally on 

 trees, but the greater number are attached to dead branches of trees, or found beneath 

 dead bark, where they no doubt feed on the smaller fungi which grow in such places. 

 Individuals of many of the species are numerous, and they are no doubt parasitised by 

 the minute Hymenoptera of the genera Sierola and Scleroderma, which are taken 

 in their company. We have lately bred forms (winged and wingless) allied to these 

 Hymenoptera from the burrows of Eimearthron, another genus of Cioidae, in this 

 country. 



