MAMMALS OF MARYLAND 



117 



Remarhs. — The specimen from 9 miles E of Oldtown, Allegany 

 County, is somewhat smaller in size and less grizzled in coloration 

 than those from farther east in the State. This animal may represent 

 an intergrade in these characters with S. c. cooperi^ the subspecies dis- 

 tributed to the north of stonei, or may actually be referable to that 

 form. As Wetzel (1955, p. 12) has pointed out, however, the ranges 

 of all measurements in these two subspecies overlap, and the variation 

 in coloration within only one sample of cooperi for one season is 

 much greater than between the various subspecies of S. cooperi. This 

 illustrates the difficulty in assigning individual specimens to sub- 

 species. Because of this, the specimen from Allegany County is pro- 

 visionally assigned to S. c. stonei^ the range of which is herein 

 considered to encompass the entire State. When more specimens from 

 the Piedmont and the Ridge and Valley sections become available for 

 study, however, it may be found that S. c. cooperi is distributed in 

 those sections, and that the specimen from Allegany County should 

 properly be assigned to that race. 



Family CAPROMYIDAE (hutias and coypus) 



NUTRIA 



Myocastor coypus (Molina) 



Mies coypus Molina, Sagg. Stor. Natur. Chili, p. 287, 1782. 

 Type locality. — Rivers of Chile. 



General distribution. — Ranges widely over southern South America ; intro- 

 duced into the United States in the 1930's, and now is established in the wild 

 in at least 16 states. 



Distribution in Maryland. — A few nutria are established in the 

 Dorchester County marshes. 



Distinguishing characteristics. — Teeth 1/1, 0/0, 1/1, 3/3, = 20; size 

 large (sometimes attaining a weight of 21 lbs.); pelage consisting of 

 2 types of hair, dense underfur, and long glossy overlying guard hairs; 

 coloration rich brown or chestnut on dorsum, paler underneath; tail 

 long and cylindrical; middle toes of hind feet connected by a basal web. 



This species superficially resembles the muskrat, from which it may 

 be readily distinguished by its larger size, cylindrical as opposed to 

 laterally compressed tail, and greater number of teeth. 



Measurements. — An adult male and female from the Blackwater 

 National Wildlife Eefuge, Dorchester County, measure externally as 



follows : Body length 571, 518 ; tail 413, ; hind foot 156, 137. Dozier 



(in correspondence) reports that the heaviest animal he examined at 

 the Fur Animal Experiment Station in Cambridge, Md., weighed 21 

 pounds. 



