MAMMALS OF MARYLAND 



119 



ters dated 18 November 1940, now in the files of the U.S. Fish and 

 Wildlife Service, he says : 



We have recently completed two new large 100 sq. ft. inclosures in marsh and 

 pond edge and have released a pair of nutria in each to study their reactions to 

 various tji^s of local habitat, etc. 



There is no record of what became of the inclosures or animals, and 

 Dozier never published, to my knowledge, the results of his study. 



Maryland kept no accurate records of its annual fur catch until 1949. 

 Prior to that, only rough estimates were made each year as to the num- 

 ber of animals trapped in the State, and no mention was ever made of 

 nutria. In 1949, when trappers were first required to report their 

 catches, four nutria were among the animals taken. N^o further nutria 

 were reported until 1956, when two were trapped in the Dorchester 

 marshes. The following year the catch was 45 and in 1958 the number 

 had risen to 52. Since then the number reported has declined. Thirty- 

 four were reported for 1959, none for 1960, and five in 1961. It appears 

 that nutria in the Maryland marshes are only precariously established. 



Specimens examined. — Dorchester County: Blackwater N'ational 

 Wildlife Refuge, 8. 



Family MURIDAE (Old World rats and mice) 

 BLACK RAT 

 Rattus rattus (Linnaeus) 



[Mus] rattus Linnaeus, Syst. nat., ed. 10, 1 : 61, 1758. 



Type locality. — Uppsala, Sweden. 



General distribution. — This is an introduced species. In the United States, it is 

 well established and abundant in the south Atlantic and Gulf Coast ports. In the 

 northeastern United States it is found in buildings along the docks of some sea- 

 ports, and at several isolated inland localities. 



Distribution in Maryland. — May occur at present in some buildings 

 along the docks in Baltimore City. 



Distinguishing characteristics. — Teeth 1/1, 0/0, 0/0, 3/3, = 16; size 

 medium; general build slender; muzzle sharp; ears large, almost 

 naked, reaching or covering the eyes when laid forward; tail slender 

 and long, at least as long as the combined length of the head and 

 body, and sometimes longer; pelage soft, but covered with coarse 

 guard hairs, giving it a harsh appearance. 



There are three color phases of this species. Some authorities have 

 considered these as distinct subspecies because of their general associa- 

 tion with distinct geographic areas. One of these color phases, known 

 as R. r. frugivorous.) has a yellowish or reddish brown dorsum, with a 

 white or yellowish abdomen, and is most commonly encountered in the 

 Mediterranean area. Another color variation, R. r. alexandrinus.) has a 



