MURIDAI—ARVICOLIN4—ARVICOLA AUSTERUS. PANY | 
that ‘“‘austerus” is not, in nature, any more “typical” than curtatus is; in 
fact, that the dark, longer-tailed Illinois strain of Pedomys is as much an 
extreme as curtatus is. The naming of the animal is a matter of judicious 
taste. We prefer to relegate the initial step of the westward departure (7. e, 
‘“‘haydeni”) to austerus, and to designate only the extreme of differentiation 
as var. curtatus. Those of opposite mind, who wish to designate every 
geographical and climatic modification by a separate binomial, will be 
obliged, in order to consistence, to do thus: restrict austerus to the dark 
Illinois animal; restrict curtatus to the Californian, Washington, and Utah 
animal; adopt haydeni for some Nebraska skins; invent a new name for 
others, as our pallid No. 3056; and then leave about 75 per cent. of Kansas 
and Nebraska skins unnamed, or else invent a fifth one for these. In this 
enumeration we neglect ‘ cinnamomeus”, as founded on a slight individual 
peculiarity of the enamel folds, which no one—certainly not Professor Baird 
—would wish to perpetuate by name, now that the real state of the case 
appears. 
TaBLe LV.— Measurements of thirteen specimens of PEDOMYS AUSTERUS CURTATUS. 
Nose%ton Tail to end 
of— 
g Locality. Collector. < 3 3 Remarks. 
= a ; Fi [ape al bee 
5 ¢ ry sed ee] re = zg | H 
= > 3 5 Ci 2 i S = & 
A a taal ° a) > os) & 5 & 
10267 | Owen Springs, Cal....| W.M. Gabb..-. |..---.|.-.--- 0.90 | 2.80 | 0.40 }.-... |...... 0.50 | ..-..| Dry; fide Cope. 
4172 | Fort Crook, Cal....-.. J. Feilner .-.--- 0.48 | 0.90 | 1.00 | 3.75 | 0.80 | 1.00 | 0.32 | 0.67 | 0.37 | Dry. 
10268 | Great Plains, W. T..--| J.G. Cooper.... |.----.|------ 1.00 | 3.87 | 0.75 | 0.85 |...... 0. 62 | 0.37 | Fresh(Cooper). 
3056 | Black Hills, Dak..... W. A. Hammond|......|.--.-.|...-.. 4.00 | 0.66 | 0.80 | 0.34 | 0.65 | 0.40 | Dry. 
3055 | Platte River.-..-..,-. Peay GRE ee | eel es ea Beer #(*) | 0.90 | 1.00 |...... 0,66) |e coer COs 
3241 | ——?, Nebr ....- ..--.| F. V. Hayden .~.|...... Spon [Pesce 4.00 | 0.80 | 0.90 }..... O275) een J--+ -do. 
4958 | Camp Floyd ..-...-.-. C.S. McCarthy..| 0.42 | 0.82 | 1.10 | 3.30 | 0.65 | 0.75 | 0.33 | 0.65 | 0.36 | Alcoholic. 
7564 | Carson Valley. Utah..|....do ......----- 0.39 | 0.79 | 1.08 | 3.25 | 0.60 | 0.95 | 0.32 | 0.65 | 0.35 |....do. 
7736 | Fort Bridger, Utah....| C. Drexler ......| 0.40 | 0.80 | 1.10 | 3.50 | 0.70 |...-.. 0.30 | 0.60 | 0.37 |..-.do. 
10038 }...... dose pee Dead iano aoa se 0.46 | 0.90 | 1.15 | 4.00 | 0.80 | 1.00 | 0.34 | 0.68 | 6.40 |....do. 
10039 |...... UE Aa or Bere Be Cea ie ee 0.39 | 0.85 | 1.05 |! 3.25 | 0.75 | 0.90 | 0.31 | 0.62 | 0.34 |= -do. 
10040 |...... (ped 2 jeoebseocod nai (peor 0.37 | 0.74 | 1.00 | 3.40 | 0.60 |...... 0.31 | 0.62 | 0.35 |..-.do. | 
LOST) | yoo 2 Gl Bas aacpes = “Sane peectit) Ags asasee 0. 38 | 0.84 | 1.05 | 3.50 | 0.70 |..---. 0.30 | 0.58 | 0.38 |..-.do. | 
* Stretched to nearly five inches ; was probably about four. 
Among the alcoholics, we find several specimens of curtatus from Utah. 
They are not in very good condition, showing little respecting the pelage 
(though the colors appear very light, much as in the Fort Crook specimen), 
but are unquestionably typical representatives of this extreme variety of aus- 
terus, and enable us to supply some additional particulars, especially as regards 
dental characters. They range from 3.25 to 4.00 inches in length; the tail- 
