RELATIVE VIABILITY IN MAMMALS AND BIRDS. 487 



still alive after 9 years' duration ; an Amaduvacle Finch after 

 7 years, a Black-headed Chestnut-Finch after 9 years, a Java 

 Sparrow of over 10 years' duration, and a Red-crested Cardinal of 

 over 8 years' duration. It is noteworthy that these figures are 

 comparable with my records and relate to species or genera which 

 have had long-lived examples here. Actually our records are 

 higher, but the number of individuals amongst which they 

 occurred is greater. 



PIOARI^. 



CaPRIMULGID^. ^Y^ Av.dur. Max. dur. 



iiidiv. Ill moiitlis. Ill months. 



Caprimidgus europceus (Nightjar) 4 4 7 



I have omitted a number of cases that lived for less than a 

 month, but this is only another instance of failure with common 

 European birds. 



PlCID^. 



Denclrocopus ^najor (Greater Spotted 16 9*8 33 



Woodpecker). 

 Centuries tricolor (Banded „ ). 1 14 14 



Melanerpes erytliroceplialuin (Red- 12 2 



headed Woodpecker). 

 Leuconerpes candidus (White-headed 2 12 16 



Woodj)ecker), 

 Gecinus viridis (Green Woodpecker) ... 9 



Colaptes auratus (Golden-winged 8 23 54 



Woodpecker). 

 lynx torquilla (Wryneck) 5 



Amongst the Woodpeckers and Wrynecks there is again 

 complete failure with British birds, whilst the other figures would 

 appear to show a low viability for the birds of this group, 

 appearing both in the average and maximum durations. 



COLIID^. ^o-of 



Indiv. 



Colius, whole genus 14 



C capensis (Cape Coly) 10 



C. castanotus (Chestnut-backed Coly). . . 2 



C. er^/^Aromefoji (Red-cheeked ,, )... 1 



C.nigricoUis (Black-necked ,, )... 1 



These small, chiefly frugivorous birds, have in proportion to their 

 size a good maximum and average duration, and must be inferred 

 to have a good viability. It is interesting to note that the whole 

 length of the intestines is remarkably short, although capacious, 

 and there can be little opportunity for intestinal putrefaction. 

 In the period under consideration the Colies were kept in the 

 Parrot House, without access to open air. 



32* 



