XIII 



PHYLUM CHORDATA 



83 



(mtcp) or hand-bones, the phalanges (ph) or finger-bones, in the 

 fore-limb ; tar sals or ankle-bones, metatarsals (mtts) or foot- 

 bones, and phalanges (ph) or toe-bones, in the hind-limb. The 

 carpals and tarsals consist typically of three rows of small nodules 

 of bone or cartilage, the proximal row containing three, the middle 

 two, and the distal five elements. The three proximal carpals are 

 called respectively radiate (ra), intermedium (int), and ulnare 

 (ul), those of the middle row the first and second centralia (en. 1, 

 en. 2), those of the third row the five distalia (dst. 1-5), the 

 separate elements being distinguished by numbers, counting from 



SCP 



HU 



a.t.1 n 



Tnlcp.i -41 



Sf( 



-I 



JF 



FK.S. 707 and 70S. Diagrams of the fore- and hind-limbs with the limb-girdles, actb. acetabulum ; 

 fil. glcnoid cavity ; p. cor. procoracoid ; / V, digits. Replacing bones en. 1 , en. 2, contralia ; 

 COR. coracoid ; dst. 15, distalia ; FE. femur ; PI. fibula ; fi. fibulare ; HU. humerus ; 

 IL. ilium; int. intermedium; IS. ischium ; mtcp. 15, metucarpals ; mtts.l 5, 

 metatarsals ; ph. phalanges; PU. pubis ; RA. radius ; ra. radiale ; SCF. scapula; TI. 

 tibia ; ti. tibiale ; UL. ulna ; ul ulnare. Investing bone CL. clavicle. 



the anterior or radial edge of the limb. In the tarsus the bones 

 of the first row are known respectively as tibiale (ti), intermedium 

 (int), and fibulare (fi), those of the second row as centralia (en. 1, 

 en. 2), and those of the third as distalia (dst. 1-5). The meta- 

 carpals (mtcp. 1-5) and metatarsals (mtts. 1-5) are five rod-like 

 bones, one articulating with each distale : they are followed by 

 the phalanges (ph), of which each digit may have from one to 

 five. The first digit of the fore-limb (Fig. 767, i) is distinguished 

 as the pollex or thumb, that of the hind-limb (Fig. 768, i) as 

 the hallux or great toe; the fifth digit of each limb (v) is the 

 minimus. 



In connection with the paired appendages are formed supporting 



