306 PROCEEDINGS OF THE ACADEMY OF [1897. 



fatuus, and westwardly into subspecies gossi. 



Gen*eral characters. — Similar in colors and appearance to Micro- 

 tis pennsylvanicus, but smaller and with a very short bicolor tail. 

 Contrasted with S. c. stonci the body measurements are somewhat 

 less, but in the same proportions. The skull of cooperi, however, is 

 relatively smaller than in stonei and the dentition much weaker. 

 The relative proportions of the skull in cooperi are about the same 

 as in fatuus, but the rostrum and mandibles of stonei and gossi are 

 relatively much broader and more massive. 



Measurements. — Average of 3 old adult females and 2 old adult 

 males from Sussex County, New Jersey and Monroe and Cambria 

 Counties, Pennsylvania ; total length 118 millimeters; tail verte- 

 brae 16.5 ; hind foot 19.5. Skulls of 2 adult males, Sussex County, 

 New Jersey and Monroe County, Pennsylvania; greatest length 

 26.5 ; greatest breadth 16. 



b. Canadian Bog Vole. Synaptomys cooperi fatuus (Bangs) ; 

 Proc. Biol. Soc. Washn., 1896, pp. 47, 48. 



Type locality. — Lake Edward, Quebec. 



Geographic distribution. — Lower east Canadian and upper Alle- 

 gheuian faunas. 



General characters. — As in cooperi. Skull much smaller and 

 dentition relatively weaker. Under parts washed with buff on 

 belly (not clear gray or plumbeous-gray as in cooperi). Tail nearly 

 unicolor. 



Measurements. — Average of 2 adults from type locality (fide 

 Bangs) ; total length 124 m. m. ; tail vertebra? 18; hind foot 18.7. 

 Skulls of 2 adult males from type locality (fide Bangs) ; greatest 

 length 25 ; greatest breadth 15.6. 



c. Carolinian Bog Vole. Synaptomys cooperi stonei (Rhoads) ; 

 Amer. Nat., 1893, pp. 53, 54. 



Type locality. — Mays Landing, Atlantic County, New Jersey. 



Geographic distribution. — Sphagnum bogs of the Carolinian 

 fauna. 



General characters. — Similar to cooperi, but somewhat larger with 

 much larger and more massive skull and broader rostrum and in- 

 cisors. Colors darker, especially on the underside, which is more 

 plumbeous or slaty (less hoary) than in cooperi? 



3 The 2 specimens taken at Chapanoke, however, are much lighter than 

 average cooperi. 



