Mr. G. R. Waterhouse 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 was 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, 1845. 



V. — Descriptions of Coleopterous Insects collected by 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 

 AmmophoruSy 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 the world or nearly so, such as 

 Feronia, Notaphus and Oryctes^ ; and, lastly, there are species 



* It is from genera like these, which have a very wide geographical range, 

 that the minor, local groups appear as it were to radiate. Those 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. Groups of high value, such as 

 classes, 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- 

 cephala, which is confined to tlie tropical zone ; and thirdly, those which are 

 restricted to a comparatively small district, such rs Manticora, which is con- 

 fined to South Africa. These genera all belong to the same family of beetles, 

 and of this family Manticora presents certainly one of the most aberrant 

 forms. The genus Cicindela would by most entomologists be regarded as 

 the typical genus of the family Cicindelidce, and here we find, as in many 

 other cases, the presumed typical genus has a universal range ; it may be 

 inquired, therefore, whether such is noi generally the case. 



I must here observe that Mr. Swainson has expressed the opinion that 

 typical genera have a great geographical range ; I was not aware, however, 

 of this fact until after the idea had been suggested to me by a tabular ar- 

 rangement which I had formed of the Mammalian order llodentia, in which 



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