FLYING DRAGONS 205 



we compare the skeleton of a Pterodactyl (such as the P. specta- 

 bilis, now under consideration) with that of a bird, we shall see 

 in its fore limbs certain very obvious differences. 



In the first place the arm or wing of a bird has only two, or 

 three, bones, instead of four, or five, as here ; secondly the outer 

 finger, which corresponds with the human " little finger " is 

 enormously elongated for the purpose of supporting the thin 

 flying membrane. In two ways, however, the skeleton of a 

 Pterodactyl does resemble that of a bird, for the bones are more 

 or less pneumatic (according to von Zittel) ; and also the position 

 of the skull at right angles to the axis bone (on the top of the 

 neck vertebrae) is a bird-like arrangement. Again, natural casts 

 of the brain cavity prove that the brain was decidedly avian, 

 though smaller in proportion to the size of the skull. The orbits 

 (for the eye) are very large and surrounded by a ring of small 

 sclerotic plates (see Fig. 74). 



In order to give rapid movement to their wings during flight, 

 they had powerful muscles in the region of the chest. These 

 were attached to a shield-like breast-bone provided with a keel 

 as in birds. But this bird-like feature is only a necessary 

 provision to enable them to fly, and does not point to any 

 relationship. 



In the year 1873 was discovered, in the lithographic stone of 

 Bavaria, at Eichstadt, a very beautiful new form of Pterodactyl. 

 This was the Khamphorhynchus phyllurus. The specimen is in a 

 remarkable state of preservation ; for the bones of the skeleton 

 are nearly all in position, while those of both wings show very 

 perfect impressions of the membranes attached to them. Its 

 long tail supported another small leaf-like membrane, which was 

 evidently used as a rudder in flight (see Fig. 75). The discovery 

 of this valuable specimen attracted much attention at the time. 



