referred lo the Genus Merione:^. 207 



Molars decidedly Iar<Ter than in M. craasn.t. 



Dimensions of tlie type (measured in the flesli) : — 



l[e:ul and body 12') mm. ; tail 125; hind foot ;^2 ; ear 17. 



Skull : median length 39 ; diagonal length 41-5 ; condylo- 

 jucisivo lou<;th 355; zygomatic breadth 21*8; nasals 15; 

 breadth of brain-case 18*3 ; bimeatal breadth 23 ; j)alatal 

 foramina 7*7 ; upper molar series, crowns O'O, alveoli 6'5. 

 Biili:e: horizontal diagonal length 17; length from back oE 

 bulla to front of premeatal swelling 15 ; suprameatal triangle, 

 lenLTth &2, height 5*6. 



ffah. Tebuk, on the Hedjaz Railway, N.W. Arabia. Alt. 

 2000'. 



7]v/)e. Young adult male. B.M. no. 10. 3. 12. 5. Original 

 number 5. Collected 3rd January, 1909, by Douglas 

 Carruther.s. 



This species agrees with M. crLX3sus in the very great size 

 of the bullae, the measurement from the back of the bulla to 

 the front of the premeatal swelling decidedly surpassing that 

 found either in the Egyptian or Tripolitan large-bulla forms. 

 In correlation therewith the suprameatal triangle is of a 

 maximum size. From that species it differs by its laro^er 

 molars and the greater posterior e.xtension of its palatine 

 foramina. 



1 have taken, as representing J/, crasstcs, a spirit-specimen 

 from Mt. Ilor, south of the Dead Sea, collected by Mr. H. C. 

 Hart, of which the skull seems closely to agree with that 

 figured by Sundevall. Another specimen in skin, from the 

 type-locality Sinai, collected by Mr. Claude Wyatt, is notice- 

 ably more ochraceous than M. pelerinus, but, owing to the 

 bullaj of this example being lost, its determination is not 

 absolutely certain. 



Meriones Uhyciis caudatus, subsp. n. 



Group h. Closely like true Uhi/eus of Lower Egypt, but 

 with markedly longer and finer tail. 



General colour above warm buff, finely ticked with brown, 

 below white with slaty bases to the hairs, as in true liln/cus. 

 Postauricular white patches fairly well marked. Tail 

 decidedly longer than head and l)ody, well-tufted, the tuft 

 beginning halfway along the upp'-r surface, and even below 

 covering more than the termin tl inch, the hairs attaining 

 lG-17 mm. in length. The tuft black, the rest buffy 

 ochraceous. 



Skull apparently (juite as in libycus, the bulla3 very largo, 

 the sn[tramtatal triangle small. 



