RELATIVE VIABILITY IN MAMMALS AND BIRDS. 5U7 



■r>„ . , , „ ,,„„ . „^^ „ No. of Av. (lur. Max. duv. 



PHALACROCORACID.E. j,,^;^. ;,, „,„„th,. in uionths. 



>S'M?a, whole genus 39 8*3 40 



S. bassana (GuYinet) 27 6 19 



*S'. leucogasti'a (Brown Gaunet) 5 15 40 



S.pisccUor (White „ ) 2 14 19 



S. serraior (Austrahan „ ) 5 8'8 16 



Phcdacrocorax^ whole genus .• 84 12 94 



P. 6r«sz7t«?ii(s (Brazilian Cormorant) .. . 9 10"5 55 



P. africanus (African ,, )... 2 23'5 36 



P. carlo (Common ,, )... 53 10*5 52 



P . carunculatus {Ko\\g\\-i-AC,Qd ,, )... 2 28 49 



P. (/r«c^t?^{s (Shag) 15 10 44 



/*.java?iici(^ (Javan Cormorant) 1 38 38 



P.Uguhris{MoViYni\\\ „ ) 1 94 94 



P.varius (Pied ,, ) 1 1 1 



Mr. J. H. Gurney [loc. cit. p. 38) quotes from H. O. Forbes 

 the record of a Common Cormorant which lived for 23 years. 

 The maximum durations on my list, ranging from nearly 8 years 

 downwards, are very much lower, whilst the average durations 

 of both Gannets and Cormorants seldom exceed one year. There 

 is the usual remarkable failure with local species — a failure which 

 would appear much greater if a considerable number of entries of 

 birds that lived less than a month had not been excluded from 

 the records. The intestinal tracts ai^e of the fish-eating type- 

 relatively large and of small calibre, but the hind-gut and c^eca 

 are very rudimentary, and there seems little opportunity for 

 intestinal putrefaction. 



PTfiTTTi;?? ^Q.oi Av. dur. Max. dur. 



JTLUilDyl!.. ji^jjj^_ in months, in mouths. 



Plotus^ whole genus 16 22 103 



Plotits ai ihinga (American Darter) 12 18 53 



P. levaillanti (Levaillant's ,, ) 2 18 34 



P. vielanog aster (Iwdisoi ,, ) 2 55'5 103 



J. H. Gurney {loc. cit. p. 38) gives an instance of an American 

 Darter of 12 years old ; I do not know of any other records. 

 The intestinal tract is similar to that of other Steganopodes, but 

 although the caeca (or single caecum) are vestigial, the hind-gut 

 is relatively more capacious and larger. These birds were kept 

 in a house (the Fish House) that was warmed in winter, aiid 

 their average duration and maximum duration show no high 

 viability. 



Summary of Steganopodes. 



Pelecans, Frigate-birds, Gannets, Cormorants and Darters, 

 whether or no they form a coherent zoological groiip, differ very 

 little in their requirements in captivity, and receive very much 

 the same treatment. They appear to me to be a group of potentin lly 



