| OCR Text |
Show 1867.] MR. G. R. CROTCH ON AZOREAN COLEOPTERA. 361 been made more in cultivated districts and the neighbourhood of towns than under canvas in remote ravines, as Madeira has been worked ; still it shows that the prevailing Atlantic forms are here only scantily represented. The characteristic genera Laparoccrus, Acalles, Tarphius, Attains (all containing eighteen or nineteen species in the other groups) have only solitary representatives. The prevailing genera are Cryptophagus (6), Homed ot a (11), Philonthus (6), Lithocharis (5) ; but they contain almost entirely introduced species. The two new genera of Rhynchophora, Asynouychus, and Neocnemis barely redeem the general poverty of tbe fauna ; both, however, are very anomalous in their affinities. Two very abundant Madeira forms (Mesites and Dasytes) are here represented by European species (M. tardii, Curt., and D. nobilis, 111.), in place of the cognate species found in the former group ; and this is the more singular, as so marked a connexion with Madeira exists in some species*. The conclusions derived from M. Drouet's lists of the other classes accord with some of these deductions : thus the almost total absence of peculiar Vertebrata (no Reptiles) would seem to show that it had been under very different conditions from the Canaries. In its land-shells, which afford a good parallel to the insects, out of seventy-six species, one-half are peculiar, one-seventh Atlantic, and one-third European ; among these Vicquesnelia, peculiar to the Azores and India, though found fossil in the Pyrenees, is the most remarkable. A detailed analysis of the 170 European species may throw some light on their origin. I have distributed them into two groups (70 possibly indigenous, and 101 almost certainly introduced by colonists), sorted into eight sections, those printed in italics being new to the Atlantic fauna. (1) Cosmopolitan species, which are introduced in articles of commerce, especially provisions, to all parts of the world. These are totally without significance in any fauna, their number depending only on the assiduity with which search is made in warehouses &c. in the sea-ports. Cutting off, therefore, the twelve here enumerated, leaves the real fauna at 200 species. Carpophilus dimidiatus. Anobium paniceum. mutilatus. Calandra oryzee. Silvanus advena. granaria. Nausibius dentatus. Tribolium ferrugineum. Corticaria serrata. Tenebrio obscurus. Ptinus testaceus. Alphitobius piceus. (2.) Species also introduced by the medium of commerce, but which may be characterized rather as frequenters of refuse: they * The most striking group in the collection is, however, the Elateridce, six fine species belonging to as many genera. 'When we remember that in the Canaries and Madeira this family is represented by the ill-defined and inconspicuous genus Coptostethus, Woll., this is very remarkable. Upon examination, however, two appear to be American and two European, thus leaving only two as really indigenous. |
