Alactaga from Mesopotamia. 15 
Linn.), a species for which the correct name is Alactaga decu- 
mana, Licht. * 
Alactaga euphratica, sp. u. 
Ears slightly shorter than the head, and rather narrow. 
Tail longer than the head and body, with a bicolor distichous 
tuft as in the other species. Hind feet short and slender, as 
compared with those of the larger A. decumana, and more like 
those of A. acontiwm, Pall.t, to which this species, though 
ae larger, seems on the whole to be most nearly 
allied. 
Fur very long and soft; above slate-coloured for half its 
length, then pale fawn, the tips black. Belly white throughout. 
Ears thinly clothed with short fawn-coloured hairs. Fore 
limbs wholly white; external surface of hind limbs fawn, 
internal white. Tail dark yellow above and below until 
within about an inch of the tip, then black for half an inch, 
and the tip white; the longest tuft-hairs at the end of the 
tail about halfan inch long ; a white stripe, as usual, from the 
front of the hip to the root of the tail. 
The skull, as compared with that of an unusually large speci- 
men of A. acontiwm, is somewhat longer, though of about the 
same breadth. ‘The brain-case is much more elongated, as 
shown by the fact that the width at the orbital constriction is 
barely half the length from this point to the occiput, while in 
A. acontium it is just two thirds. The anterior palatine fora- 
mina are longer and more open, the muzzle (at their centre) is 
decidedly broader, and the upper molar series is distinctly 
longer in A. euphratica than in A. acontiwm. 'The compara- 
tive measurements of the two skulls are given below. 
Dimensions (in inches and tenths). 
do. 2. 
Headtandybadyacsermre sca: 56 5:0 
Mail=vertebraay seca vas se ase 6°75 as 
Hind foot, without claws...... 2:05 2:04 
Heel to tip of fifth toe........ 1:25 1:28 
Tea sor syaevretea eo eBder sey eyesore 3 ae 1:25 
ISR rae ob od odd ov Has DEON 1:15 114 
Measurements of the Skulls of A. euphratica and A. acontium. 
A. euphratica 3. A. acontium g. 
Motalelena thi errr ier 115 1:10 
Zygomatic breadth ........ a 0:85 
Breadth of brain-case ...... 0°63 0-63 
Abh. Akad. Berl. 1825, p. 154, tab. vi. 
Zoogr. Ross.-As. p. 182 (1811). 
