208 Annals of the Carnegie Museum. 



ports a circular facet on its lateral aspect, to articulate in life with 

 the surface described above on the tarso-metatarsus. Thus it is 

 that this bone is so mobile, and can be thrown backwards to a con- 

 siderable distance. Below, it bears a trochlea for the rear phalanx of 

 hallux, which reaches high on its shaft on the digital side of the bone, 

 being faintly grooved on the other. The entire length of this seg- 

 ment is 1.7 centimeters. 



At the proximal end of the first phalanx of hallux, the trochlear 

 surface is far more extensive than its opposed surface on the first 

 metatarsal, being fully half as broad again. The shaft is rather 

 slender, gently curved throughout, convex upwards, and subcircular 

 on section. Its distal trochlear surface is principally on the under 

 side of the bone. It is narrow transversely, and shows a shallow 

 median longitudinal groove. The sides of this extremity are marked 

 by pits for ligamentous attachment. It measures in extreme length 

 4.6 centimeters, being the longest phalanx of the pes. 



Its osseous claw is rather more than moderately curved, and ex- 

 hibits the usual trochlear surface and the tubercle for tendinal insertion. 

 The distance from this latter point to the apex measures 1.6 centimeters. 

 Both the convex surface above and the concave surface beneath is uni- 

 formly rounded off, while the bone is laterally compressed. A groove 

 distinctly marks it on either side, but is not quite carried to the apex. 



Second digit has three phalanges including the ungual one ; the 

 proximal phalanx has all the characters as given for first joint of hallux ; 

 it, however, is distinguished by a prominent tubercle to the inner side 

 of the articular surface for the trochlea of tarso-metatarsus. The bone 

 is rather stouter and somewhat shorter. The second joint is a still 

 shorter and a slighter bone ; its proximal trochlea is concave from 

 above, downwards, very slightly convex in the opposite direction. 

 The shafts of these bones are not curved to the degree found in 

 the first joint of hallux, and the proximal ones are always the straight- 

 est. Agreeing even in minor details, the ungual phalanx of this 

 second digit is smaller than the one found in the first toe, but 

 shows about the same amount of curvature. These three joints measure 

 from proximal to distal one, respectively 4.4, 3.1 and i.i centimeters; 

 the ungual joint being measured as T measured the bony claw of the 

 first digit. 



The four joints of the middle or third digit have the general char- 

 acters as given for these phalanges above. Measuring them in the 



