24 



FORTH AMEEICAN FAUNA. 



[No. 37. 



grizzled with buffy white; underparts huffy white or Hght ochraceous- 

 buff, the bases of hairs blackish brown. 



ShuU. — Largest of the group; relatively long and narrow; sagittal 

 crest well developed (in adults) ; interorbital region broad; nasals long 

 and broad, usually squarely truncated posteriorly; premaxillae nar- 

 row; palate long, extending from 2 to 4 mm. behind plane of molars; 

 palatal foramina rather narrow; interpterygoid fossa broad; audital 

 bullae moderately inflated. 



Measurements. — ^Adult male from Gunston, Va: Total length, 665; 

 tail vertebrae, 153; hind foot, 88. Adult male from Sandy Spring, 

 Md.: 573; 145; 82. Average of 4 adult females from District of 

 Columbia and Virginia: 557; 139; 83. STcuTl: Adult male:^ Condylo- 

 basal length, 97.3-102.5 (average 97.8); palatal length, 55-59.5 

 (57.4) ; postpalatal length, 34.5-37.7 (36.2) ; length of nasals, 39.7-41.8 

 (40.8) ; zygomatic breadth, 63-69.2 (65.9) ; breadth across mastoids, 

 44.5-50.2 (46.9); least interorbital breadth, 25-29.2 (27.1); breadth 

 of rostrum, 20.6-23.7 (21.7); maxillary tooth row, 21-21.9 (21.3). 

 Adult female: 2 Condylo-basal length, 90.4-91.8 (91.2); palatal length 

 50.2-56 (53.1); postpalatal length, 33.7-36.3 (34.9); length of nasals, 

 36.8-40.6 (38.7); zygomatic breadth, 59.5-62 (61.2); breadth across 

 mastoids, 44-45.8 (44.7) ; least interorbital breadth, 23.5-26.5 (24.9); 

 breadth of rostrum, 19.7-21.3 (20.5); maxillary tooth row, 20.5-22.4 

 (21.2). 



Remarks. — The southern woodchuck is a rather large animal of 

 massive skull and pale color. With a wide range in the Middle 

 States, it grades into a smaller and darker form (rufescens) in the 

 southern parts of New York, Michigan, and Wisconsin. Specimens 

 from northern Illinois (Lake Forest and Willow Springs) and northern 

 Indiana (Rose Lawn and Lake Maxinkuckee) are typical of monax, but 

 those from Delavan, Wis., and southwestern Michigan are inter- 

 mediate between monax and rufescens. Specimens from Marble Cave, 

 Mo., and from Johnson County, Iowa, are typical, but a small series 

 from the vicinity of Lawrence, Kans., seems to indicate the presence 

 there of a large form, skulls of females, especially, being much larger 

 than those of females from Maryland and Virginia and equaling in 

 size skulls of males from that region. The hind feet also average 

 about 16 per cent longer in the Kansas animal (3 specimens). Addi- 

 tional material from that region may require naming the form. 



Specimens examined. — Total number, 75, as follows: 



Alabama: Ardell, 3. 



District of Columbia: Washington, 6. 



Georgia: Young Harris, 1, 



1 Six specimens from M-aryland, Virginia, West Virginia, and Pennsylvania. 



2 Five specimens from Virginia, District of Columbia, and Pennsylvania. 



