288 FOSSIL BIRDS 



chiefly in forms confined to islands ; and this is a result in full 

 accordance with that already attained in the foregoing treatise on 

 Extermination. In Europe a not very remote glacial epoch 

 has left its indubitable trace in the former southerly extension of 

 some forms Avhose home is now in more northern districts. The 

 comparatively-few known Pliocene Birds are mostly referable to 

 existing genera, though the majority of the species are extinct ; 

 but in the Lower Miocene we meet with a considerable number of 

 extinct genera; while, both here and in the Upper Eocene, the 

 occurrence in Europe of genera either identical with or nearly 

 allied to those which now inhabit only the tropics or lands lying 

 even further to the southward is particularly instructive. Some 

 of them are at present peculiar to the Ethiopian Eegion, and among 

 these are especially to be noted Laurillardia, Fsittacus (Parrot), and 

 Serpentarius (Secretary-bird), with perhaps Cryptcn-nis — a supposed 

 HoRNBiLL, and Necrornis — referred to the Plantain -eat1';r. 

 Others have their modern representatives in Asia, as Gallus 

 and Fhasianus ; while others again have now a still Avider range, 

 though no longer occurring anywhere in the temperate zones, 

 as Collocalia (Swift), Leptoptilus (Adjutant), and, perhaps most 

 suggestive of all, Trogon, for the Family to which it belongs, 

 though inhabiting both the Ethiopian and Indian Regions, is now 

 more largely developed in the Neotropical Regions than elsewhere. 

 This last case is in some measure analogous to that of the Tapiridm 

 among Mammals, though no African Tapir is known. But in a 

 general way all the lessons which Fossil Ornithology so far teaches 

 seem to be in perfect harmony with what we learn from a study 

 of Fossil Mammals ; and, when palaeontologists generally come to 

 admit the fact, which some of their leaders have long since recog- 

 nized,^ that their study, though one of infinitely great meaning to 

 the geologist, is but a branch of Zoology, no one can doubt of 

 the valuable results that will follow from their co-operation. 

 But letting this pass, it is important to notice that already 

 in the Lower Miocene, if not in the Upper Eocene pei'iods, 

 there is sufficient evidence to shew that many of the chief groups 

 of Birds as we now know them had been already established, and 



^ The views of the elder Agassiz on this point are notorious ; those of Prof. 

 Alphonse Milne -Edwards were declared prior to the publication of his great 

 work, which itself is a perpetual witness of their truth. Prof. Huxley many 

 years ago in a speech, which though never fully reported is well remembered 

 by some of those who heard it, most rightly asserted that " Palseontology is 

 simply the biology of the past ; and a fossil animal differs only in this regard 

 froni a stuffed one, that the one has been dead longer than the other, for ages 

 instead of for days"(/iis, 1866, p. 413). The present petrified condition of 

 some geologists requires a life-imparting impulse, and they — be it said with all 

 due respect — need bringing into touch with those who would gladly accept their 

 assistance or even their guidance. — A. N. 



