THE TARSUS 



107 



facet in front for articulation with the tibial tarsal, and sometimes a small articular 

 surface below for the central tarsal bone. Its plantar surface forms with the smooth 

 inner surface of the body a groove for the deep flexor tendon (Sulcus musculi flexoris 

 hallucis longi). Its inner surface has a prominence on the lower part for the at- 

 tachment of the lateral ligament. The external surface of the body is flattened, 

 except below, where there is a rough prominence for the attachment of the lateral 



Fossa 



Facets for lihiiil 

 tarsal bone 



Fig 79. — Right Fibular Taksai. 

 Bone of Horse, Antmuor 

 View. (,\fter Scliinaltz, 

 Atlas d. Anat. d. Pferdes.) 



Facet for 

 tibial tarsal 



Facet for 



central 



tarsal 



Facet for 

 central tarsal 



Fig. 80. — Right Fourth Tar- 

 sal Bone of Horse, 

 Upper Surface. (After 

 Schmaltz, Atlas d. Anat. 

 d. Pferdes.) 



Surface for 

 tibial tarsal 



Fi<;. 81. — Right Central Tar- 

 sal Bone of Horse, 

 Upper Surface. (After 

 Schmaltz, Atlas d. Anat. 

 d. Pferdes.) 



ligament. The anterior or dorsal border is concave in its length, smooth and 

 rounded in its upper piirt. About its middle is a blunt-pointed projection (Pro- 

 cessus cochlearis) which bears facets on its inner and lower surfaces for articulation 

 with the tibial tarsal bone, and is roughened outwardly for ligamentous attachment. 

 Below this are two facets for the tibial tarsal, and an extensive rough fossa which 

 concurs in the formation of the sinus tarsi. The posterior or plantar border is 



Fused first and 

 second tarsals 



Facets for cen- 

 tral tarsal 

 acets for central 

 tarsal 



Third tarsal 



Fig. 82. — Right First, Second, and Third Tarsal 

 Bones of Horse, Upper Surface. (After 

 Schmaltz, Atlas d. Anat. d. Pferdes.) 



Second (inter- 

 nal) metatar- 

 sal 



Facets for sec 



ond and third 



tarsals 



Fourth (external) 

 metatarsal 



Facet for third 

 tarsal 



Facets for 

 fourth tar- 

 sal 



Fig. 83. — Proximal Articular Surfaces of Left 

 Metatarsal Bones of Horse. • (After 

 Schmaltz, Atlas d. Anat. d. Pferdes.) 



straight and thick, and widens a little at either end; it is rough, and gives attach- 

 ment to the long plantar ligament. 



The Central Tarsal Bone 

 The central tarsal bone (Os tarsi centrale, scaphoid, or navicular) is irregularly 

 quadrilateral, and is situated between the tibial tarsal above and the third tarsal 

 below. It is flattened from above downward, and may be described as having two 



