Mr. G. R. Waterliouse on some Coleopterous Insects. 19 between leaves and petals in the situation of the colours ; and the location of the colours of the petals in the rete, a fact hitherto unnoticed, and one which may hereafter throw light on some interesting points of vegetable physiology. Reference Avas made to another kind of colours, also found in the leaves and petals. These, with their peculiarities, which may prove not devoid of practical interest, together with some other matters connected with the subject or suggested by it, remain to be brought forward at some future time. London, June 9, IS 15. V. — Descrij)tions of Coleopterous Insects collected hy Charles Darwin, Esq., in the Galapagos Islands. By George R. Waterhouse, Esq. The insects here described are nearly all of small size, and none of them display any brilliant colouring. Some of the species are referable to a little group found in Chile and Peru, — the genus Ammophorus, a genus hitherto only found in those parts ; others appertain to a genus {Anchonus) which is almost confined to the West Indian islands and the northern parts of South America. Again, in the collection under consideration are species of ge-nera which are found all over tlie world or nearly so, such as Fei'onia, Notaphus and Ori/ctes* ; and, lastly, there are species * It is from genera like these, v.-hicb liave a very wide geographical range, that the minor, local groups appear as it were to radiate. Tliose genera which are confined to comparatively limited districts, often containing but few species, and also often presenting very remarkable abnormal modifica-tions of structure, are in most cases referable to some family which has re-presentatives in most parts of the world, (iroups of high value, such as classe.-., are never confined to any particular quarter of the globe ; and even when we descend to families, restricted as they now are by natu-ralists, it is comparatively rare to find them so defined as not to embrace species from widely separated localities. Genera may be arranged under three principal categories as regards their geographical distribution. First may be noticed those of universal range, such as Cicindela; secondly, those which occur in both hemispheres but affect particular zones, such as Mega-cepfiala, which is confined to the tro])icaI zone ; and thirdly, those which are restricted to a coinparatively small district, such n^ M antic or a, which is con-fined to South Africa, 'lliese genera all belong to the same family of beetles, and of this family Miutticora presents certainly one of the most aberrant forms. The genus Cichulela would by most entomologists be regarded as the typical genus of the family Ciciiuhdida, and here we find, as in many other cases, tlie presumed t} pical genus has a universal range ; it may be inquired, therefore, whether such is not generally tlie case. I must here observe that Mr. Swainson has expressed the opinion that typical genera have a great geographical range ; 1 was not aware, however, of this fact until after the idea had been suggested to nie by a tabular ar-rangement which I had formed of the Mammalian order Ilodentia, in which C2
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