446 DR. p. CHALMERS MITCHELL ON LONGEVITY AND 



No. of Av. dur. Max. dur. 



Indiv. in months. in months. 



Sciurus variabilis (Variable Squirrel) 2 73 75 



US', variegatus (Red-bellied ,, ) 13 36 129 



^S'. vulgaris (Common „ ) 77 6 20 



S. vulpina (Vulpine „ ) 10 36 85 



XerMs, whole genus 24 9'8 41 



X. erythro'pvjs (Red-footed Ground 7 8 19 



Squirrel). 



X. getulus (Getulian Ground 11 10*5 41 



Squirrel). 



X. setosus (Bristly Ground 6 10 15 



Squirrel). 



Tamias, whole genus 16 26 84 



1\ asiaticus (Asiatic Ground Squirrel) 3 8 23 



T. lateralis C^ide-atriped „ „ ) 1 21 21 



1\ striatus (Chipping Squirrel) 12 31 84 



Pierom^/s, whole genus 5 61 163 



P. alho-rufus (Red-bellied Flying- 1 163 163 



Squirrel). 



P. inornatus (Large Red Flying- 12 2 



Squirrel). 



P. leucogenys (White Cheeked 1 101 101 



Flying- Squirrel). 



P. inagnificus (Red-bellied Flying- 1 36 36 



Squirrel). 



P. oral (Large Brown Flying- 13 3 



Squirrel). 



Sciurojiterus, whole genus 14 15 61 



*.S'.j'?m6H«^t(.s (Grey Flying-Squirrel) . 11 13'7 61 



S. layardi (Layard's ,,,,). 1 1 1 



^. volucella (American ,, ,, ) . 2 30 37 

 = volans. 



Spermophilus, whole germs 24 17 132 



.*b'. citillus (European Souslik) ... 5 7*4 11 



S. grammurtis (Line-tailed ,,)... 1 119 119 



^S'. mexicanus (Mexican „ ) ... 3 47 132 



S. mongolicus (Mongolian „ ) ... 4 10*7 22 



'S. tridecimlineatus (Thirteen-striped 11 5'5 22 



Souslik). 



Arctomys, whole genus 23 64 164 



A. caudatus (Long-tailed Marmot) .1 15 15 



A. Mmalayamcs {JlimLa]a,ja,n „ ) . 1 79 79 



A. hodgsoni (Hodgson's ,, ) • 2 73*5 74 



A. marmotta (Alpine ,, ) . 10 82 164 



xi. mmiax (Quebec ?> ) • 9 57 116 



Cynomys ludovicianus (Prairie ,, ) . 48 30 98 



I am unacquainted with any published observations as to the 



