RELATIVE VIABILITY IN MAMMALS AND BIRDS. 527 



for a Great Bustard, is no great age for so large a bird ; the figures of 

 average duration are fairly good in compai/ison with the maximum 

 durations. These birds have been kept ahnost altogether in open- 

 air paddocks, and it vi^ould appear that their constitutional 

 viability is not high in proportion to their size. The whole 

 alimentary tract is very short in proportion to the size of tlie 

 birds, but the hind-gut and cieca are relatively extremely 

 capacious. 



P„ rN „ ^o. of Av. dur. Max. dur. 



SOPHIID.E & CAEIAMID.IC. j^.j;^, ;„ ,^^„,^t,^^ ;„ ^^^^^^j,^ 



Psojyhki, whole genus of) 17*7 90 



P. a'e;j/^««s (Common Ti'umpeter) ... 15 17"5 90 



P. fe?tco/;)to'a (White-backed „ ) ... G 19-5 34 



P. virid's (Green-winged ,, ) ••• ^^ 16'5 32 



Cariamct cristata (Brazilian Cariaina) 20 49 151 



Chiongci burmelsterl (Burmeister's 6 31 65 



Cariama). 



I do not know of any published references to the ages of 

 Trumpeters and Cariamas. The alimentary tract of these birds 

 is much of the same character as that of the Bustards, but the 

 cjeca and hind-gut are relatively rather less capacious. The birds 

 •have been kept in an aviary with heated interior and open-air 

 compartments. The record of between 12 and 13 years for a 

 Brazilian Cariama, and the figures of average duration appear 

 to show that the Cariamas have a higher viability than the 

 Trumpeters. The former are larger birds, and the difi'erence 

 may be merely the familiar size correlation. 



Pdt-tt^j:- No. of Av. dur. Max. dur. 



URLIDiE. InAxv. in months, in months. 



Gi'us, whole genus 42 72 514 



G. americana (American Crane) 5 34 82 



G. antigone (E-Astern tiiirus ,, ) 7 64 191 



G. ausiralasiana (Australian Crane) 10 .68 129 



G. canadensis (Canadian ,, ) 4 35 96 



G. comviunls (Common ii ) ^ 1^5 514 



G. jajjonensis (Mantchurian ,, ) 8 59 306 



G. monachus (Hooded ,, ) 1 99 99 



Anthr ojwides, \\ho\e genviii 40 46"5 227 



A. carunc'ulata (Wattled Crane) 9 34 59 



^1. leucauchen (White-necked Crane) 1 184 184 



A. leucogeranos (Asiatic White ,, ) 9 34 84 



A. 2>aradisea (Stanley ,, ) 8 58 227 



A. virgo (Demoiselle ,, ) 13 46 104 



Balearica pctvojiina (Crowned ,, ) 7 50 141 



£. regitlo7-iom (Cape ,, ) 14 43 170 



Mr. J. H. Gurney has recorded [loc. cit. p. 38) a Common Crane 

 of 40 years (from the Gardens of this Society) and a White-necked 

 Crane of 28 years from the Amsterdam Gardens. Tlie longest 



