RUMINANTS. 529 



appearance in the periodically hornless Deer, and their larger size 

 in the absolutely hornless Musks, is further illustrated by the 

 presence not only of canines, but of a pair of laniariform incisors 

 in the upper jaw of the CamelidtB. In the Camel and Dromedary 

 the upper canines are formidable for their size and shape, but do 

 not project beyond the lips like the tusks of the Musk-deer ; they 

 are more feeble in the Llamas and Vicugnas (PI. 133, fig. 2, c), 

 and are always of smaller size in the females than the males. 

 The inferior canines, moreover, retain their laniary form in the 

 CamelidcB, and are more erect in position than in the ordinary 

 Ruminants : they are separated by a short diastema from the 

 incisors in the Auchenics, (ib. c). The true nature of the 

 corresponding teeth in the ordinary Ruminants, in which they 

 are procumbent and form part of the same series with the 

 incisors, is always indicated by the lateness of their development, 

 and often by some peculiarity of form: thus in the Moschus they 

 are smaller and more pointed than the incisors, and in the Giraffe 

 they have a much larger crown which is bilobed : their ordinary 

 proportions and position, as presented by a large Antelope, the 

 Gnu, is shown in PI. 134, fig. 9, c. The laniariform tooth in 

 the intermaxillary bone of the Camelida, which represents the 

 upper and outer incisor, is smaller than the true canine which 

 is placed behind it in the Camel and Dromedary : but in the 

 Vicugna (PI. 133, fig. 2, i.) it is as large as, or larger than the 

 true canine. The lower incisors in the genus Auchenia (ib. i) 

 have long and narrow crowns, directed straight forward and 

 placed side by side : in Camelus the crowns of the lower incisors 

 are oblong, depressed, spatulate or leaf-shaped, with a sinuous 

 bend concave above ; and they overlap each other, as shown in 

 PI. 134, fig. 8, the outer contour of the series describing half 

 of an ellipse. In the Giraffe the incisors describe a semicircle. In 

 most of the ordinary Ruminants the lower incisors are arranged 

 in a transverse line at the extremity of the jaw. In these the 

 first is the largest, and the second and third decrease in size, and 

 to a greater degree in the Deer and Antelopes than in the Elk, 

 the Sheep and the Ox : their crowns are trenchant and procumbent, 



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