464 On the Irish Otter. 
LXII.— The Irish Otter, By Martin A. C, Hinton. 
(Published by permission of the Trustees of the British Museum.) 
Lone ago Ogilby (P. Z. S. 1834, p. 111) described the Irish 
otter as a distinct species, Lutra roensis, “on account of the 
intensity of its colouring, which approaches nearly to black 
both on the upper and under surface ; of the less extent of 
the pale colour beneath the throat as compared with the 
common otter, L. vulgaris, Linn., as it exists in England ; 
and of some difference in the size of the ears and in the 
proportions of other parts.’ Ogilby added that he had 
“long considered the Irish otter as constituting a distinct 
species,” 
The type of ZL. roensis was presented to the Zoological 
Society by Miss Anna Moody of the Roe Mills, Newtown 
Lemavaddy, near Londonderry; later it passed into the 
British Museum (reg. no. 57. 12. 14. 4), where it is now 
preserved. The nearly black colour described by Ogilby 
has become, from exposure, a nearly uniform deep reddish 
brown. 
The Museum has just received three female otters from 
Co. Galway, caught during the last winter. These, as regards 
colour, accord perfectly with Ogilby’s description; they are 
much darker (practically black above) than any English 
specimens examined by me. In my opinion, therefore, the 
Irish otter should be regarded as a distinct subspecies, for 
which the name Z. J. roensts is available. Such a variation 
characterized by colour-saturation is, of course, exactly what 
is to be expected in the more humid climate of Ireland. 
The following measurements will form a useful supplement 
to those given in Miller’s ‘Catalogue of the Mammals of 
Western Europe’ :—Females 1 and 2: head and body 710, 
635 mm. ; tail 430, 440; hind foot 114, 114; ear 25, 25. 
Skulls. 
Lutra lutra roensis. 
Females, Co. Galway. 
Pe ry ca: 2, 3. 
Condylo-basal length........ ie Ac 108°3 +. 
Zygomatic breadth.......... ae 64:7 65°8 65°3 
Mastoid breadth 22 ac4.0% asi. 58°4 60 61:2 60:4 
Postorbital constriction...... 14:5 14:2 ra 13°8 
Interorbital constriction .... 169 18 19-4 18:7 
Breadth of rostrumovercanines. 265°2 24-7 24:7 24-7 
Occipital depth ......../,.: she eS 34:7 on 
Maxillary tooth-row (canine~m.). 33:1 30'7 332 32°38 
bE LG 6) 6 | ERE OR er Sie sche bach 66:6 68 68:2 68 
Upper earanssiali. 00 .ihe. 104x7'9 10679 10°5x 79 107X799 
Dipper molar iins. seen mak 77 X10'6 77X10 79% 10-7 7EXL0G 
Lower carnassial length .... 12°6 12 12-9 11:3. 
