440 Bibliographical Notices. 



scribed as well as figured in the author's brochure on the Arvicolce of 

 Li£ge. They are as follows : 



1. A. monticola. Size of the A. amphibius. Tail pale ash, a little 

 shorter than half the length of the body .fur yellowish grey, mixt with 

 pale yellowish at the sides, whitish ash beneath and on the feet. (13 

 pairs of ribs ?) 



Inhabits the Pyrenees. 



2. A. Savii. Size of the A. arvalis. External ears a little hairy, 

 much shorter than the fur : tail a little shorter than one- third of the 

 body ; of two colours, brownish above, whitish beneath : fur brown- 

 grey above, ash colour beneath : feet pale ash. (14 pairs of ribs.) 



Inhabits Tuscany, Lombardy, and probably all Italy. 



3. A. subterraneus. Size a little larger than that of the A. arvalis. 

 Ears a little shorter, of the length of the fur, nearly naked ; eyes very 

 small : tail one third the length of the body, of two colours, blackish 

 above, white beneath : far blackish grey above, ash- colour or whitish 

 on the abdomen only : feet deep ash. (13 pairs of ribs.) 



Inhabits Belgium, French Flanders, and the environs of Paris, but 

 no other parts of Europe, unless it be the Mus agrestis of Linne, in 

 which case it is found also in Sweden*. 



4. A. duodecim-costatus. Size of the A. arvalis. Tail a little longer 

 than one third of the body. Twelve pairs of ribs : six lumbar vertebra. 

 Fur} . . . 



Inhabits the South of France and the frontiers of Switzerland, but 

 supposed to be very rare. No skin of it exists, and only the osteo- 

 logy of it is known. The 12 pairs of ribs distinguish it from every 

 other species excepting the A. socialis, and from this it may be known 

 by its longer tail, and by having 6 instead of 5 lumbar vertebrae. 



The A. destructor is a species found in Italy, which appears to 

 have been recognised by M. De Selys-Longchamps and M. Savi 

 nearly about the same time. It was originally described by the 

 former in the ' Revue Zoologique,' under the name of A. Musignani, 

 but this name is exchanged here for destructor out of courtesy to 

 M. Savi, who had previously thus designated it. It is closely allied 

 to the A. amphibius, from which it may be known by a difference in 

 the fur, which much resembles that of the Mus decumanus, and by the 

 nearly uniform whitish-ash colour of the under parts. But its great 

 peculiarity resides in the form of the cranium, which is said to be 

 quite different from that of its congeners. This part is represented, 



* This species was first characterized by M. Baillon in 1 834, under the 

 name of Lemmas pratensis, but it had been discovered by M. De Selys- 

 Longchamps as long previously as 1831. 



