464 



MANUAL OF ELEMENTARY ZOOLOGY 



from the attacks of carnivorous animals upon their turn of 

 speed, which is attained partly by their walking, not upon 

 the soles of their feet, but upon the tips of their toes, so 

 that the power of their limbs is concentrated. This is 

 expressed by the statement that they are unguligrade. 

 Animals which, like dogs and cats, 

 walk upon the under surface of the toes 

 and never place the palm or instep 

 upon the ground are digitigrade. Those 

 which, like bears and man, walk upon 

 the whole sole of the foot are said to 

 be plantigrade. Those which, like the 

 rabbit, run upon the toes only, but 

 when at rest apply the whole sole to the 

 ground, are subplantigrade. 



In Ungulata the metacarpal and meta- 

 tarsal bones are lengthened, 



Ungulata. ., ^ , . ° , , ' 



so that what seem to be 

 " knees " are really the wrist and ankle 

 joints, high above the ground. The 

 first digit is wanting, and usually some 

 of the others are also missing. The 

 ends of those which remain are encased 

 in the broad horny coverings known as 

 hoofs. This does not apply to the 

 elephants, which have five toes with 

 short metacarpals and metatarsals. 

 Hoofs are very broad nails, which cover 

 The bones the sides and part of the ends of the 

 toes. Like other nails, they grow from 

 above downwards. The part which 

 "" ct'euff^k.^nnon covers the front and side of the last 

 bone (fused third and phalanx (the " coffin bone " of the 



fourth metatarsals) : f \ ■ V j 1 - 1 • 1 1 



ph., phalanges. horse) is formed by a thickened ring 



of skin above it, known as the " coronary 

 cushion." That which covers the end of the digit (the 

 so-called "sole") is formed by the whole surface of 

 the skin it covers. In correspondence with their diet, 

 ungulates have broad grinding teeth, whose surfaces are 

 generally ridged or lophodont, though in the omnivorous 

 pigs they are knobbed or bunodont. Ungulata fall into 



Fig. 340. 



of the foot of an ox. 

 — From Thomson 



