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resemblance to that of a falcon, as also, according to Prof. Owen, in its 
anatomical structure. Each caudal vertebra bore a pair of rectrices, but all 
the rest of the body was apparently destitute of feathers, otherwise traces 
of them must have been found upon a slab which has preserved even the 
smallest details of a fine down. 
Prof. Vogt regards Archceopteryx as neither a reptile nor a bird. It 
constitutes according to him an intermediate type of the most strongly marked 
description, confirming the views of Prof. Huxley, who has united reptiles 
and birds, under the name of Sauropsida, as forming a single great section 
of the Vertebrata. It is one of the most important signposts on the road 
which has been followed by the class of birds in its gradual differentiation 
from the reptiles from which it originated. A bird by its integument and 
hinder limbs, it is a reptile in all the rest of its structure ; and thus its con- 
formation can only be understood if we accept the evolution of birds by 
progressive development from certain types of reptiles. The Cretaceous birds 
described by Prof. Marsh indicate a later step in the same direction. 
In discussing the stages by which Archceopteryx passed to arrive at the 
form under which we know it, and the mode in which adaptation for. flight 
has acted upon the different parts of the body, Prof. Vogt shows, in the 
first place, that this adaptation in Vertebrata is by no means necessarily 
combined with that of an upright position. This is seen in the Pterosauria 
and the Bats. The structure of the hind feet that occurs in the Dinosauria, 
the Archceopteryx , and in birds, is therefore, he thinks, independent of the 
faculty of flight, and only stands in relation to the possibility of sustaining 
the body upon the hinder feet alone ; and hence the resemblance in this 
respect between Dinosauria and birds by no means indicates real affinity. 
At the utmost he would regard it as possibly indicating a genetic connexion 
between the Dinosauria and the Struthious birds, but this would involve a 
multiple origin of the class of birds. 
The search in deposits older than the Upper Jurassic for reptiles which 
may be related to Archceopteryx , and thus indicate earlier stages in the 
process of evolution, would seem to be vain, since the fossils we possess are 
destitute of tegumentary parts, and it is very difficult to say a priori with 
what cutaneous structures these creatures were covered. At the same time, 
as Prof. Vogt points out, there is complete homology between the scales or 
spines of reptiles and the feathers of birds. The reptilian structures, he 
remarks, differ in no respect from the wart-like stumps which appear in the 
embryo bird as the first traces of plumage ; the feather of the bird is only a 
reptile’s scale further developed ; and the reptile’s scale is a feather which 
has remained in the embryonic condition. The feathers of Archceopteryx , 
which are so perfect, must undoubtedly have been preceded in some pre- 
existing reptiles by cutaneous structures representing persistently the dif- 
ferent stages of the embryonic development of the feathers. We may, 
therefore, imagine the ancestors of the Archceopteryx as lizard-like, terrestrial 
reptiles, having feet with five, hooked, free digits, showing no modification 
of the skeleton, but having the skin furnished at different points with 
elongated warts, downy plumes, and rudimentary feathers, not yet fitted for 
flight, but susceptible of further development in the course of generations. — 
(Bibl. Univ., December 15, 1879 ; Ann. and Mag. Nat. Hist., February, 1880.) 
