HORNS IN BIRDS 



head shows a pair of elevations of the bone which suggest 

 exactly the bony horn basis in certain mammals. It 

 seems to us very probable that if nothing were known 

 concerning this crane save its skull-cap, it would have 

 gone down to posterity as a horned bird. And very 

 likely the tiny horn on the head of the horned screamer 

 (Palamedea cormita), a close ally of the screamer Chauna, 

 as we note on another page, would have been quoted as 

 the last vestige in a living bird of a former horned race. 

 But the crane is not horned, only crested. The deep 

 note of cranes, of intense loudness, is familiar to all 

 visitors to the Zoo, and is especially to be heard at evening. 

 It is aided by the long windpipe, which is coiled like a 

 trumpet and adds of course by this increase of length 

 to the volume of the sound produced. This special 

 arrangement is not found in our crowned cranes, who 

 are thus less specialized and more primitive representa- 

 tives of the crane tribe than the remaining forms. 



THE SCREAMER 



South America is the home of many waning races 

 of birds and beasts ; in its dense forests there lurk repre- 

 sentatives of whole groups, which once flourished abun- 

 dantly upon the the land, but are now reduced to scarce 

 waifs and strays, the flotsam and jetsam of a previous 

 order of things. There is one living " diprotodont " 

 marsupial, the sole remnant of the otherwise extinct 

 family Epanorthidce ; the rail-like Heliornis or Podoa 

 forms, with two allies in Africa and the East, the sole 

 remains of a group of birds possibly antecedent to the 

 widely spread rails and water hens of the rest of the 

 world ; the mysterious Guacharo or oil-bird is of a type 

 peculiar to itself at present, and the " Four-footed " 

 bird of the northern parts of the South American con- 

 tinent (Opisthocomus cristatus) has not a single close ally 

 living anywhere else. Among this wreckage are to be 



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