238 Bangs — MammaU from Hamilton Li let, Labrador. 



chest, and about vent. Feet, liands, and tail dull gray, hairy. Tail with 

 a long pencil nearly equaling length of tail. 



Measurements. — The three specimens measured as follows: 



Skull — n\Q skull of 4166, (J' old adult, measures : basal length, 28.6 ; zy- 

 gomatic breadth, 19.8; mastoid breadth, 14.2; alveolar length of upper 

 molar series, 7.6; incisive foramen, 5.6. That of an adult male D. tor- 

 giijilas from Petschora, Russia (No. 3()21, collection of Gerrit S. Miller, Jr.), 

 measures: basal length, 27.4; zygomatic breadth, 19; mastoid breadth, 

 14; alveolar length of upper molar series, 7.4; incisive foramen, 6.8. 



These specimens are of approximably equal age, so that they furnish a 

 very satisfactory basis for comparison. The skull of D. torquatus, though 

 actually slightly smaller, gives the impression of greater strength and 

 massiveness. This is chiefly due to its liroader, less deflected rostrum and 

 slightly shorter, broader l)rain case. While the width of rostrum is less 

 and the deflection of dorsal outline greater in D. hudsonius, the rostral 

 depth at the root of the zygoma is slightly greater in D. torquatus. Au- 

 dital bulhe in D. tuidsonius distinctly larger and less globular than in 

 D. torquatus. 



Teeth. — As has recently been pointed out,* there is a minute supple- 

 mental anterior internal loop in the posterior lower molar of Dicrostonyx 

 huAlsonlHs which is apparently absent in the Old World species. Other- 

 wise the dentition calls for no special comment. 



Synaptomys (Mictomys) innuitus (True). 



Only one specimen was collected. Dr. C. Hart IMerriani and Mr. Gerrit 

 S. Miller, Jr., have kindly compared Ihis specimen with the tyi)e of in- 

 nuitn.s from Fort Ciiimo, Labrador, with the following results : The Ham- 

 ilton Inlet specimen is younger than the type of innuitus, Init is larger, 

 the hind foot measuring :> mm. more and the skull being actually larger; 

 the tail is also longer. It is a jnty that only one specimen from each 

 locality is in existence, as more material from Labrador would probably 

 show that two well marked forms occur there, as is the case with Erotomys 

 and probably with Phenaconiys ungava also. The n^easurements of the 

 si)ecimen, No. 3972, (^ young adult, are : total length, 114; tail vertebrse, 

 25; hind foot, 21. 



* Miller, North American Fauna, No. 12, p. 39, foot-note, July 23, 1896. 



