referred to the Genus Meriones. 969 
bulla 42°8 ; condylo-incisive length 39; zygomatic breadth 
24°5 ; nasals 16:2; interorbital breadth 8; breadth of brain- 
case 18; meatal breadth 22°8; palatine foramina 7°6 ; 
upper molar series 5°8. Bullee: horizontal diagonal length 
16:2; back of bulla to front of meatal swelling 12°8; supra- 
meatal triangle, length 5, height 3. 
Hab. Syrian Desert. Type from Karyatein (spelt Kar- 
geten in Stieler’s Atlas). Alt. 2000’. Another specimen 
from a point 320 km. east of the Dead Sea, 3000’. 
Type. Adult male. B.M. no. 5. 7. 2. 2. Original 
number 27. Collected 3rd March, 1905, by Douglas 
Carruthers, 
Of these gerbils with large bulle—all once referred to 
M. erythrourus,—the true bearer of that name occurs in 
Afghanistan, ranging westwards through Persia to the edge 
of the highlands ; then in the lower littoral country comes 
the smaller Jf. charon, succeeded again in the Syrian 
desert by the present species, which, though more like true 
erythrourus, i3 distinguishable by its longer feet and larger 
teeth. 
Mertones charon, sp. 0. 
A small species with terminally crested tail, allied to 
M. longifrons. 
Size a little less than in M. longifrons. General colour 
above finely speckled sandy buff (“ pinkish buff’? darkened 
by the brown points of the hairs), the tone warmer on the 
posterior back. Under surface white, the lateral line of 
demarcation not specially sharply defined. Cheeks greyish, 
the postorbital and postauricular whitish spots scarcely 
marked. Ears rather short, coloured like the head.. Hands 
and feet white ; soles with the median area of their proximal 
halves naked, their terminal halves hairy. Tail not very 
long, its greater portion short-haired, dull buffy, not more 
ochraceous than the body, its terminal 25-30 mm. with an 
upper crest of black hairs which may attain 15 mm. in length 
at the tip. 
Skull very much as in M. /ongitfrons, but the bulle less 
swollen, their antero-internal extension considerably less. 
Suprameatal triangle nearly as high as long. 
Dimensions of the type :— 
Head and body 129 mm.; tail 132; hind foot 29:5; 
ear 17:5. 
Skull; median length 37:2; diagonal length to back of 
bulla 38°3; condylo-incisive length 33°5 ; zygomatic breadth 
