212 THE TRANSFORMATIONS OF THE ANIMAL WORLD 



which ornament, like a semi-circular crown, the 

 sides and posterior part of the head. 



The class of Birds presents us with little more 

 than the cephalic protuberance of the helmeted 

 Casoar; on the other hand, the Mammals testify, 

 on this point, to a most varied specialization. 

 Every one is acquainted with the nasal and frontal 

 horns of the Rhinoceros family, the frontal bony 

 pegs of the Antelopes and the Bovidse, and, 

 lastly, the bony and elegantly ramified prolonga- 

 tions which constitute the antlers of our Cervidse. 

 In this last family, the complication of the antlers 

 has been pushed to the extreme in certain Pliocene 

 species ; for example, the Cervus dicranius of the 

 Val d'Arno, whose cranium, exhibited in the Florence 

 Museum, is a real branching bush. In geological 

 times we find, besides those groups actually in 

 existence, other types of horned animals. The 

 Titanotheria, gigantic Imparidigitse almost the 

 size of Elephants, bore at the limit of the frontal 

 and nasal bones two strong and divergent bony 

 horns. In the family of the Cervidae, the male Proto- 

 ceras of the Oligocene of Montana, had three pairs 

 of bony cranial protuberances, one on the anterior 

 border of the maxillary and two unequal ones on 

 the frontal bones. The Sivatherium of the Miocene 

 of India, a relation of the Giraffes, presented at the 

 exterior angles of the frontal bones two powerful 

 ramified bony branches, and another pair at the 

 anterior part of the forehead. Finally, the very 

 specialized American Branch, the Dinocerata of the 

 order Amblypods, may be reckoned among^the 

 most colossal and strange of terrestrial Mammals, 



