Additions to the British Mammalia. 599 



Mis,y p. 49., from a specimen taken in a ditch in Norfolk, may 

 be considered as representing an example of S, remifer ; but 

 the specific term ciliatus is not sufficiently definite, as it refers 

 to a character possessed by all the water shrews. 



Bank Campagnol (Arvi'cola ripa^ria). ,vn 



The authors of our various British faunas all agree iri In- 

 cluding but two species of true campagnol (genus Arvicola 

 Auct.), The first, A. amphibia, the water campagnol, or 

 water rat ; the second, the A. agrestis, ikfus agrestis of 

 Ray, our common short-tailed field campagnol. Both these 

 species are too well known to require description; but it will 

 be necessary that I should refer occasionally to the specific 

 distinctions of the latter, in order more clearly to point out 

 the differential characters between that and the Arvicola 

 riparia, or bank campagnol, which I believe to be new. ,; '" 



ilfus agrestis Ray^ Arvicola agrestis Flemings Field Campagnol.— Length 

 of the head and body. Sin. 6 lines ; head only, 1 in. \\ line; tail, 1 in. 1 line; 

 ears, b\ lines. Head large, muzzle blunt ; ears rounded, nearly hid in 

 the fur; tail not quite one third the length of the body; fur. soft, all 

 the upper parts reddish yellow brown, ash-grey beneath. 



Arvicola riparia. Bank Campagnol. — Length of head and body,3in/4 lines'; 

 head only, 1 in. and half a line; tail, 1 in. 8 lines ; ears, 5 lines. Head 

 and muzzle stout ; ears rounded, more prominent than in the field 

 campagnol ; tail exactly half the length of the body ; colour of the f^r 

 deep chestnut brown above, ash-grey beneath, hairs on the tail long, ail- 

 pressed, extending beyond the end of the last vertebra. The exterif^l 

 differences are in the size and colour of the body, and relative length of 

 tail. Two skeletons of each species have been set up, aiid the following 

 are the comparative measurements : — 



Field Campagnol. Bank Campagnol. 

 inches, lines, iiiches. lines. 



Length of the head - - - - \^\ ;.v«P ^O^id 



From the first dorsal vertebra to the last 10 - -p ^ 



Length of the six lumbar vertebrae - 11^ -^uo^ ^/tcYji^J 



First dorsal vertebra, to the tuberosity! „ g '^^^ >>>'nu->( I nj 

 of the ischium ^ ', ,.,/;. if; <.; .■;, a^i -jnil .*^ aW 



Length of the OS innominata -: {'^ 7;|,'P . ^ • ^fihr/v *v^fiii;<: ^{j 



Sacral vertebra, to the end of the tail "-"^ '1 "' 

 Scapula - - - - - 



Humerus - - - - - 



Olecranon to the carpus - - - 



Femur - - - - - 



Tibia 



Os calcis to the end of the longest toe - 



The number of cervical, dorsal, lumbar, and sacr^ vertebrae is the 

 same in both, viz. seven, thirteen, six, and one, respectively : but the tail 

 of the field campagnol has but nineteen vertebrae ; that of the bank cam- 

 pagnol contains four more, making twenty-three. It will also be seen, by 

 a reference to the measurement, that the relative dimensions of the body 

 and tail, in each, are nearly reversed. The field campagnol has the cavity 

 of the thorax of much larger size than that of the bank campagnol, the 

 ribs of greater expansion, and the sternum longer. The head of the bank 



Q Q 4 . 'V -•> \\ \w\ 



