MURIDAE—SIGMODONTES—HESPEROMYS LEUCOPUS. 73 
TaBLe XV.—Measurements of twelve specimens purporting to be HESPEROMYS “ AUSTERUS”’. 
e Nose to Tail i end 3 3 
2 Locality. Collector. = < = Remarks, 
5 Hy ee | Bar| OCoe | ratte) oa lrraaes! =| £ 
A | put. ebra a & | q i 
= 
G. Suckley....| 0.52 | 1.00 | 1.18 |...... SEN) | Kenoce 0.48 | 0.80 |.-.-.- Alcoholic. 
0. 87 | 1. 02 | 2.67 | 2.76 oo 0.33 | 0.72 | eccrine Alcoholic. 
1.00 | 1.20 | 3.10 | 3.20 |-..... 0 34 | ONTO Soon Alcoholic. 
0.70 | 0.86 | 1.80 | 1.38 |...... 0.27 | 0.60 |..-... Alc.; young. 
0.68 | 0.83 | 1.85 | 1.50 |...... 0.28 | 0.56 |...... Ale.; young. 
*9880 | Vancouver's Island ....---- 0.80 | 1.00 | 2.40 | 2.40 }.-.... 0.35 | 0.70 |...... Alcoholic, 
8327 | Washington Territory -...-.| J.G.Swan ....|...-..]..----]...--- 3.10 | 3. 0. 62 | Dry. 
229 | Spokan, Wash. Ter..-...--.-- BELG Off) 2) Shee Been Been lossee- 3.00 | 2. ; 0.59 | Dry. 
916 | Puget Sound, Wash. Ter ....| G. Suckley....|..---.|.----.]------ 2.75 | 3. . 8 | 0.49 | Dry. 
-.do ..- 3. . 82 | 0.64 | Dry. 
= ie Pi ebyy Eeese | Ep one 0.79 | 0.52 | Dry. 
do 540) eee | eens 0.75 | 0.45 | Dry. 
| 
*This specimen is remarkably blackish, with very pure white feet, and seen by itself would readily suggest a 
distinction of species from ordinary leucopus. It is the extremo of tho ‘‘austerus”’ style. 
This little table is curious and suggestive. The twelve specimens happen 
to differ among themselves in size and proportions nearly as much as the 
whole eastern series of /eucopus does, and show more variation than would 
be required to establish several distinct species upon the slight basis that has 
been often employed. And after allowing a wide margin for chances of error 
in measurement (always a safe thing to do in dealing with stuffed skins of 
small mammals), discrepancies remain that cannot be explained away. The tail 
varies an inch, and the ears and feet are quite as variable. To sum up (with 
special reference to ‘‘boylii”, that we are about to discuss) : The tail, com- 
pared with the trunk, ranges from less than the average of eastern /eucopus 
up to nearly the average of “‘myoides” or “boylii”. The ears range from the 
smallest of dewcopus to the largest of ‘“boylii”. The feet have the ordinary 
range of either /ewcopus or “boylii”. Nothing further is needed to prove our 
point. 
In analyzing our species of Hesperomys, Professor Baird put “ myoides” 
and “boylii” together, because they agreed in a length of tail exceeding the 
average of true /eucopus. Of “boylii” he says :—‘‘No cheek-pouches? Tail 
three-quarters of an inch longer than the [head and] body”; and of “myo- 
ides”:—* With cheek-pouches. Tail a quarter of an inch longer than the head 
and body.” The supposed distinctions of color do not hold ; for No. 1313 
(“myoides”, Burlington, Vt.) and No. 578 (“boylii”, Shoalwater Bay) are almost 
precisely alike in color—much more so than two specimens of ‘boylii” (No. 
578 and No. 356, for example) are. No. 356, the type of ‘“‘boylii”, is the very 
