VOL. XXVII.] PHILOSOPHICAL TRANSACTIONS. 50^ 



The first is called astragalus. This is articulated above with the tibia, hav- 

 ing a depression in the middle 3 inches, which receives, and two protuberances 

 at the sides, which are received by the tibia, 34- inches. It receives the talus 

 below with a surface 4 inches diameter. On the inside it sends forth a large 

 protuberance, and on the outside both it and the talus are received by the ex- 

 ternal malleolus for the space of 2 inches. Before it is received by the os navi- 

 culare during the space of 4-l inches. It weighs 6f . 



The talus is a very irregular bone ; it is protuberant behind from the astragalus 

 44- inches. This protuberance is in circumference at the extremity 10 inches, 

 and at its neck 8 inches; below it is very rugous on the inside. It sends forth 

 a protuberance, which is received by the astragalus, as in human subjects. It 

 has three remarkable surfaces, viz. one upon which the astragalus rests, at its 

 upper side; one at the fore part, articulated with the ossa cuneiformiaj and the 

 outside, for the fibula. It weighs 1 lb. 



The OS naviculare is 10-l inches in circumference, 1 inch thick, concave be- 

 hind, where it receives the astragalus, and convex before, with its different 

 surfaces, viz. one where it is articulated with the bone of the toe on the inside, 

 and one for each of the three wedge-like bones. It weighs 4§. 



The bones of the second rank of the tarsus are called the three wedge-like 

 bones, two of which are articulated at the back part with the os naviculare, and 

 the third partly with the talus and partly with the os naviculare; each of them 

 is about 1 inch thick ; that on the inner side is the least, being from the right 

 to the left 1 inch thick ; it weighs fift ; the middle 2 inches, in weight §ij; 

 and that on the outside 34- inches, in weight f iij. This last has two surfaces at 

 the fore part, where it is articulated with the two utmost bones of the meta- 

 tarsus. The middle bone of the tarsus being only received by the middle bone 

 of the metatarsus. 



The external bone of the metatarsus is very irregular: it is articulated behind 

 with the external os cuneiforme, where it is about 2 inches from above to below; 

 from whence, its external surface being very rugous, it becomes gradually 

 smaller, being somewhat concave below, and protuberant above, till it terminates 

 in a round extremity. It weighs §ijfb. 



The second is a short thick bone, 8 inches in circumference, and 24- inches 

 long; in weight fijfj). This receives the first bone of the toe, which is 44- 

 inches in circumference, and 2 long; and receives the second bone of the same 

 toe, being 3 in circumference, and 1^ long; greater at its upper, and smaller 

 at its lower extremity, to which is affixed a small bone. These weigh f iijf^. 



The middle bone of the metatarsus is the largest of all those belonging to 

 the toe, being 7 inches round, and 5 long; §iiij in weight. It receives the first 



4 f2 



