Bibliographical Notices. 855 



to destroy the specific claims of the insects which have accidentally 

 given them birth. And I should frequently, therefore, be inclined 

 to look upon such-like media as lapsus naturcB rather than as con- 

 nective, — at any rate where they are only of rare experience and 

 exist between forms the limits of which are otherwise clear and un- 

 ambiguous. With these few remarks, which I have somewhat pro- 

 longed, as likely to apply in instances besides the present one, it will 

 be sufficient to add that the O. bicolor (which, if my identification 

 of it be correct, would appear to attain a rather larger size in Madeira 

 than the ordinary type) may be distinguished, for the most part, 

 from O. liquiduSy not merely by its superior bulk, but by its less 

 posteriorly-acuminated outline, by its usually just perceptibly darker 

 and less brassy hue, and by its legs and antennae being, almost 

 invariably, both of a more diluted testaceous tinge and (proportion- 

 ably) a trifle longer. It is an abundant insect, during the spring 

 and summer months, in certain parts of Madeira, at rather low and 

 intermediate elevations. In May of 1849, whilst encamped in the 

 Ribeiro de Santa Luzia with the Rev. R. T. Lowe, I captured it in 

 the utmost profusion from amongst the long grass and flowers imme- 

 diately outside my tent, — and in company with the O. liquidus, 

 which thus, at all events, cannot be a local variety of it." 



The mere British collector who studies as well as names his insects 

 should get this work, if he has not already got it, on account of the 

 many valuable "clearings" and detailed descriptions of British 

 genera. In this aspect the book is singularly valuable and import- 

 ant, and did space permit, we could refer to many passages in proof. 

 We may perhaps hope to see the other orders described by Mr. Wol- 

 laston ; and we trust that his present noble and costly contribution 

 will not stand long alone, but will be followed by at least another 

 volume, which will certainly never appear, unless its author be en- 

 couraged by the sale of this splendid volume, and unless, too, he con- 

 scientiously thinks, that he will be promoting the knowledge of the 

 marvellous works of an Almighty hand. Such a work will then form, 

 so far as the insect portion of the multitudinous Annulosa is con- 

 cerned, a point for the historian of the geographical distribution of 

 animals to reason on ; and should Messrs. Lowe and Wollaston ever 

 publish an illustrated volume on the Land Mollusca of Madeira, the 

 zoologist and palaeontologist will be supplied with data for reasoning 

 on the extremely difficult but intensely interesting question of the 

 "distribution" and what is called "extinction" of species. Insects, 

 Crustacea — especially the Entomostraca — and Snails (Madeira is a 

 Helico-metropolis) form certainly the most lasting animated features 

 of any land ; drought and other circumstances which destroy Mam- 

 malia, Birds, Fishes, Reptiles and other orders having hardly any 

 perceptible influence on these enduring works of " Him, who made 

 the worlds." 



23* 



