40 
MAMMALIAN GALLERY. 
Ti aguUna or Chevrotains, and (3) the Pecora, or the Oxen, Ante- 
lopes and Deer, and the Giraffe. 
The molars of all these ^lammals consist of two pairs of crescent- 
shaped lobes, and their stomach is composed of four, or, rarely, 
three divisions, from one of which their food is returned to their 
Fi-. FT 
Stomach of a Sheep, cut open to show the internal structure. 
ce, oesophagus, or gullet ; ru, rumen, or paunch ; ret, reticulum, or honey- 
comb; psalterium, or manvplies; ah, abomasum; py, pylorus; dii, 
duodenum, the commencement of the small intestine. 
mouth after it has been swallowed, in order to be chewed a second 
time, a process known as ruminating or chewing the cud. 
(1) The Tylopoda, the Camels and Llamas, are distinguished 
from the other Ungulates by their elongate and prehensile upper 
lip, their thick woolly fur, long neck and legs, two-toed feet, the 
})ads of skin beneath their hoofs (whence the name Tylopoda, or 
pad-footed their eomplicated stomach, whose walls contain a 
])eculiar set of large cavities, the so-called water-cells (suj)posed, 
though with much doubt, to be for the jmrpose of storing water), 
their oval blood -corpuscles (all other jMammals having round 
ones), and by numerous other sjiecial characters. The first genus, 
Camelus, contains the Dromedary and the Camel, both domesti- 
cated, and ranging from North Africa, through Arabia, Persia, and 
Central Asia, to India. The Dromedary, with one hump on the 
hack, is not known in a wild state; while the two-humped Canud 
[C. bactrianus) has recently been discovered living in a wild state by 
Russian travellers in the mountain-ranges of Central Asia. Even 
these, however, are supposed by some authors to be the descendants 
of domesticated individuals. The humps are large masses of fatty 
substance serving as a store of nutriment, which during periods 
of scarcity of food is gradually absorbed, and replenished when 
