i8a NATURAL SCIENCE. March, 



" restorations " are as utterly wrong and misleading in this respect 

 as they are in others. 



Archaoptevyx, unlike any other known bird, bore quills on its 

 tibiae. These are not either remiges or rectrices — and, indeed, the 

 lateral aeroplane in front of the tail is not strictly made up of rectrices. 

 In the absence of a better name, I will call them tibial quills. These 

 appear to have lain in a single plane, which is the plane of flexion of 

 the leg, the plane in which femur, tibia, and metatarsals all lie when 

 the limb is bent ; and they were apparently arranged in two series 

 along the surfaces corresponding to the anterior and posterior 

 surfaces of the human tibia, i.e., the extensor and flexor surfaces. 

 The number of them cannot be made out with certainty. The longest 

 appear to have measured a little over 30 mm. in length. How they 

 were placed in reference to the muscles I cannot say, and though 

 they appear to have lain in a single plane, they may perhaps — though 

 I do not believe it — have been " breeches," as they have been 

 described. They extended along the whole length of the tibia, and 

 certain appearances in the region between the left leg and the tail in 

 the Berlin specimen suggest that the flexor-series extended also to the 

 region of the femur. 



CoYerts are recognisable with certainty over the primary and 

 secondary quills of the wings, especially the left wing, but they are 

 not nearly so well preserved as the more robust quills. They appear 

 to have been very slender, and now lie at an angle of about 40 

 to the quills. This deflection may have been due to the action of a 

 stream of water passing over the dead bird when it first came to rest 

 where it was finally fossilised ; and, if so, the animal must have come 

 to rest with its head up-stream, as one would naturally suppose. 



The appearances in the fossil do not justify any statement as to 

 the coverts in the tail or over the tibial quills. 



Contour feathers may be recognised with certainty only in the 

 cervical region. Three are well preserved between the right hand 

 and the label bearing the number 11 in Plate I. (facing p. 122). I 

 believe I have recognised others ventral to the fourth and fifth 

 cervical vertebrae ; but this is far from certain. As to the covering 

 of the rest of the body, we are in the dark. 



IV. — Habits. 



ArchaopteryxwaiS an arboreal quadruped fitted for flight, if not for 

 prolonged flight. 



First, as to quadrupedalism and attitude. — I have already 

 (p. 120) pointed out that the digits I, II, III of the hand are long 

 and slender and flexible ; and that each metacarpal and phalanx of 

 these digits is curved, the concavity being ventral ; and that the 

 tubercles for the insertion of the flexor and extensor muscles of some 

 of these phalanges are distinctly recognisable. To this I would now 



