268 REPORT ON ZOOLOGY, MDCCCXLIV. 



Alps around the Guldbrandsthal. Of Lemnus insularis it is said, "resembles 

 still more closely L. agrestis, and with similar teeth to the latter, but with a 

 longer tail (1-1 to 2") and somewhat larger ears. Found, according to 

 Natterer, upon the east Gothiau Scheereu." The right upon the part of 

 these, especially the latter species, to be regarded as distinct does not appear 

 proved to the Reporter by these short accounts. 



Myodes schisticolor has been (S. 144) established by Liljeborg -. ashy gray 

 with a large reddish brown spot upon the posterior part of the back. From 

 the northern part of the Guldbrandsthal, in Norway. Sundevall, who had 

 demonstrated beforehand a specimen of this new species found in Dalecarlia, 

 remarks that the teeth possess the same form as in Mus Lemnus, but that 

 the anterior claws, just as in the species of Hypudseus, are not larger than 

 the posterior; in Mus lemnus the fore are much larger than the hind nails. 

 Two young ones of the same new species have also been found at Kuopio, in 

 Finland. 



Th. von Middendorf has given a provisional Report of the species of 

 Lemmings observed in his journey in the north-east of Siberia. (Bullet, de 

 la Classe Phys. Math, de Petersb. iii, p. 219.) Instead of increasing Mid- 

 dendorf has diminished the number of the species, since he reduces all the 

 Lemmings observed in Tamirlaud to two species, and in so doing directs 

 attention also in the case of these animals to the great conformity that pre- 

 vails in the whole Fauna of the highest north. The multiplication of the 

 species was due to the great diversities of size aud colour, dependent upon 

 age and season, presented by the same animal, the correct reduction of which 

 to the unity of the species can only result from observing them in a state of 

 nature. The two species occurring in Tamiiiand range, according to Middeii- 

 dorf's convictions, throughout the whole north of Asia and America. 



1. Mi/odes hudsonius, Forst. and Rich., unto which belong as synonymous 

 M/ts torqtidtus, Pall., Lemnus vngulatus, Baer., and Myodes grcenlandicus, 

 Traill. Extends from the east coast of the White Sea through Siberia and 



D 



North America, and thus completely encircles the arctic regions of the globe, 

 and reaches probably from the polar circle as far north as there is terra 

 firma. It does not descend to the limits of vegetation, and like all true 

 arctic natives assumes a white coat during the winter. Even the double claws 

 belong, as it would seem, in their most perfect state, only to old males in 

 their winter garb. 



2. Myodes obcnsis, Brants., is synonymous with Middendorf to Hyp. 

 migratorius, Licht., Arc. helvolus, Rich., and Georh. listens, Ev. A more 

 southern species than the preceding being seen by Middendorf not far above 

 74 ; inhabits low and even woody plains, and appears to occur upon the 

 whole Ural as far as its southern branch-chains. It does not become white 

 in winter, though the change of colour is otherwise very considerable ; 

 when in its full summer dress it approximates the M. norvccjicus. The 



