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Show GALAPAGOS ARCHIPELAGO. Oct. 1835. although the kind of vegetation consumed in each case is so very different. Mr. Bell has given the name to the genus from the shortness of the snout: indeed, the form of the mouth mav almost be compared to that of the tortoise. One is te~pted to suppose this is an adaptation to their herbivorous appetites. It is very interesting thus to find a well-characterized genus, having its aquatic and terrestrial species, belonging to so confined a portion of the world. The former species is by far the most remarkable, because it is the only existing Saurian, which can properly be said to be a maritime animal. I should perhaps have mentioned earlier, that in the whole archipelago, there is only one rill of fresh water that reaches the coast; yet these reptiles frequent the seabeaches, and no other parts in all the islands. Moreover, there is no existing lizard, as far as I am aware, excepting this Amblyrhyncus, that feeds exclusively on aquatic productions. If, however, we refer to epochs long past, we shall find such habits common to several gigantic animals of the Saurian race. To conclude with the order of reptiles. Of snakes there are several species, but all harmless. Of toads and frogs there are none. I was surprised at this, considering how well the temperate and damp woods in the elevated parts appeared adapted for their habits. It recalled to my mind the singular statement made by Bory St. Vincent,* namely, that none of this family are to be found on the volcanic islands in the great oceans. There certainly appears to be some foundation for this observation; which is the more remarkable, when compared with the case of lizards, which are generally among the earliest colonists of the smallest islet. It may be asked, whether this is not owing to the different facilities of transport through salt-water, of the eggs of the latter protected by a calcareous coat, and of the slimy spawn of the former ? As I at first observed, these islands are not so remarkable '~~< Voyage aux quatre lies d' Afl'ique. Oct. 1835. NUMBER OF REPTILES. for the number of species of reptiles, as for that of individuals; when we remember the well-beaten paths made b the many hundred great tortoises-the warrens of the te!restr~ al Amblyrhyncus-and the groups of the aquatic species basking on the coast-rocks-we must admit that there is no other quarter of the world, where this order replaces the herbivorous mammalia in so extraordinary a manner. J t is worthy of observation by the geologist (who will probabl refer. back in his mind to the secondary periods, when th~ Saurians were developed with dimensions, which at the present day can be compared only to the cetaceous mammalia), that this archipelago, instead of possessing a humid climate and rank vegetation, cannot be considered otherwise than extremely arid, and for an equatorial region, remarkably temperate. T.o finish with the zoology : I took great pains in collecting the msects, but I was surprised to find> even in the high and damp region, how exceedingly few they were in number. The forests of Tierra del Fuego are certainly much more barren ; but with that exception I never collected in so poor a country. In the lower and sterile land I took seven species of Heteromera, and a few other insects ; but in the fine thriving w?ods towards the centre of the islands, although I persevermgly swept under the bushes during all kinds of weather, I obtained only a few minute Diptera and Hymenoptera. Owing to this scarcity of insects, nearly all the birds live in the lower country; and the part which any one would have thought much the most favourable for them, is frequented only by a few of the small tyrant-flycatchers. I do not believe a single bird, excepting the water-rail, is confined to the damp region. Mr. Waterhouse informs me that nearly all the insects belong to European forms, and that the! do not by any means possess an equatorial character. I d.Id not take a single one of large size, or of bright colours. This last observation applies equally to the birds and fl~wers.. It is worthy of remark, that the only land-bird With bnght colours, is that species of tyrant-flycatcher, which |