184 U. S. P. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



LUTRA, Linn. 



Lutra, LINN. "Syst. Nat. I, 1735." 



GEN. CH. Body elongated, feet short, palmated ; digits distinct, the central longer than the exterior ones ; tail moderate, 

 depressed, rounded at the sides. 



The skull of the otters, in general, resembles that of the Martinae, but is more depressed, and 

 more contracted behind the orbital processes. The top of the skull is nearly straight, and 

 almost parallel with the margin of the lower jaw. 



The dental formula is: incisors, ^ ; canines, ^ 5 prcmolars, *~^ ; molars, ^ = j-^ = 36. 



The genus is very widely distributed, being found in all quarters of the globe. The species 

 resemble each other, and are separated with great difficulty, owing to their plain colors ; they 

 differ in the extent and character of the naked muffle, the palmation and hairiness of the feet, 

 details of the skull, &c. America has one strongly marked species, with several varieties, 

 according to authors ; whether the Lutra calif ornica, of Gray, from the Pacific slope, be really 

 distinct from that of the Atlantic, is yet to be finally ascertained by the examination of more 

 specimens than are now accessible to the student. 



LUTRA CANADENSIS, Sab. 



American Otter. 



Lutra canadensis, Jos. SABINE, Zool. App. Frankl. Jour., 1823, 653. 



F. COT. Diet, des Sc. Nat. XXVII, 18*3, 242. 



GRIFFITHS' Cuv. V, 1827, 130. 



RICH. F. B. Am. 1, 1829, 57. 



FISCHER, Syn. 1829, 225. 



PR. MAXIM. Reise in das innere Nord Am. I, 1839, 211. 



DEKAT, N. Y. Zool. I, 1842, 39 ; pi. iii, f. 1 - r pi. xxxiii, f. 1, 2, 3. (Skull.) 



An.. & BACH. N. A. Quad. II, 1851, 2 ; pi. li. 



GIEBEL, Saugt. 1855, 789. 

 Lutra lataxina, F. Cuv. Diet, des Sc. Nat. XXVII, 1823, 242. IB. Suppl. Buff. I, Mammif. 1831, 203. 



FISCHER, Synopsis, 1829. 

 Lutra brasiliensis, HARLAN, F. Am. 1825, 72. 



GODMAN, Am. N. H. I, 1831, 222. 



Luira hudsonica, F. Ccv. Suppl. Buffon, I, Mammif. 1831, 194. 

 Lutra vulgaris, var. canadensis, WAGNER, Suppl. Schreb. II, 1841, 256. 

 " Lataxina mollis, GRAT".' 

 Lutra canadcnsis, var. Lataxina mollis, GRAY, Aud. &. Bach. N. A. Quad. Ill, 1853, 97 ; pi. cxxii. 



Sp. CH. Length about 4| feet. Muzzle longer than wide, sending down a naked point along the median lino of the upper 

 lip anteriorly. Under surfaces of the feet so covered with hair towards the circumference as completely to isolate the naked 

 pads of the tips. A hairy strip extending forward from beneath the carpus on the palm. Color above, liver brown, barely 

 lighter beneath; inferior surface and sides of head and neck dirty whitish. 



General form musteline. Head broad and blunt, neck long. Body depressed, low ; legs 

 short. Tail long, tapering, much depressed, about three-fifths as long as the head and body. 



The naked muzzle is quite large, its posterior outline running up into the forehead, so as to 

 be as long, or rather longer than broad ; this outline is decidedly A -shaped, the acute angle 

 behind ; the lines are not quite straight, but slightly sigmoid. The anterior outline of the 



' I have not been able to find this quotation. 



