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Show 1880.] LIFE OP ANIMALS IN ZOOLOGICAL GARDENS. 319 order the lifetime of which is ascertained follows fo the impossibility of giving definite dates for the duration of life of Rabbits, Guinea-pigs, and some other small species of the same kind. Sheep and Goats cause the differences between the numbers respecting Ruminantia. W e were also obliged to leave out of consideration several sorts of Parrots-namely, Nymphicus, Bolborhynchus, and others. Of Fowls and Pigeons only the wild species have been selected for the register, The results are as follows :- 205 Mammals : total of age, 829 years 11 months 27 days ; mean duration of life per head, 3 years 9 months 26 days. 784 Birds: total of age, 3549 years - months 7 days; mean duration per head, 4 years 4 months 23 days. Together, 989 animals, 4379 years - months 4 days; mean duration of life per head, 4 years 5 months 6 days. The mean duration of life of the animals which died in the year 1879 is 2 years 4 months 27 days. This, so much shorter time than that mentioned before, will be easily explained by the fact that the mortality is much greater in the first days after the arrival of animals in a zoological garden. I am certain that similar statistics would give very useful hints to persons interested in such matters; and I wish that this branch of knowledge were cultivated more specially than it has been heretofore. Specification of Average Lifetime. MAMMALIA. Chiroptera Equidse AVES. Number of animals at hand Jan. 1, 1880. 36 1 42 60 6 10 7 103 33 5 108 260 86 83 84 389 Number of animals the age of which is ascertained. 36 1 42 8 6 10 7 95 33 5 54 233 17 22 1 64 355 Total of age. yrs. 88 0 154 24 19 88 31 418 149 8 347 492 47 49 8 328 2121 mths. 0 2 7 10 6 8 2 9 1 4 7 4 9 0 7 0 11 days 22 29 23 1 16 2 23 1 26 16 23 10 17 18 14 5 28 i Mean age of individuals. yrs. 2 0 3 3 3 8 4 4 4 1 6 2 2 2 8 5 5 mths. 5 2 8 1 3 10 5 4 6 8 5 1 9 2 7 1 11 days 12 29 8 7 3 16 18 28 9 6 6 11 26 23 14 15 26 PROC. ZOOL. Soc-1880, No. XXL 21 |