new African }f(iiniimln. 545 



Tacmyoryctks. 

 The comparison of a scric;-* of Mole-Rats Iroiu the I'^lf^oii 

 district in the lliuUl Collection with those in the British 

 Muscnin shows that these animals are fairly constant locally, 

 and, like as they are externally, have cranial ehar:ieters 

 which enaljle me to distinj^uish the f()ll()win;j; dilTerent ftjrms 

 among those hitherto referred to my T. ibcaiius. 



Taclnjoryctcs unkol'ue, sp. n. 



Distinguished by the fact that, even in the oldest speci- 

 mens, the parietal ridges never quite nu-et to form a single 

 median sagittal crest, the space between them on the crown 

 never less than about 12-3 mm. Frontal [)art of ridges, aljove 

 the intertemporal constriction, strongly developed, high, 

 and in some cases meeting in the middle line. Spread of 

 zygomata about as in ibeanus. 



Nasals fairly broad anteriorly. Teeth rather larger than 

 in the tyi)e of T. ibeanus. Bulhe rather small. 



Size medium. General colour rather pale. Proportion of 

 plumbeous specimens small. 



Dimensions of type (measured in flesh) : — 



Head and body 200 mm.; tail 60; hind foot 28. 



Condylo-basilar length 43 ; zygomatic breadth 33 ; nasals 

 17*7x()"7; brain-case* 19"2xiy; upper molar scries 

 (crowns) O'l; length of bulla 10-2. 



Hub. Burnmba, Ankole, S. Uganda. 



Type. Old male. B.jM. no. 4. 2. 6. 25. Original number 

 583. Collected 1st August, 1903, by W. G. Doggett. Pre- 

 sented by Col. E. Delme-Radelitte. Eight specimens. 



Tachyoryctes doemon, sp. n. 



Size markedly smaller than in T. ibeatius. Sagittal crest 

 linear in adults, owing to the meeting of the parietal ridges 

 in the middle line, as is also the ease in all the succeeding 

 species ; the crest itself is, however, not very strongly 

 developed in the present form. Zygomata strongly bowed 

 out anteriorly, forming a marked projecting shoulder on each 

 side, much more so than in the next species. Nasals medmni 

 or narrow, a slight re-entiant curve generally present on 

 each side. 



Colour a fairly dark fulvous, all three adult specimens 

 with dark faces. 



Dimensions of type skull (no external measurements 

 avaihdjic) : — 



Condylo-basal length 12 mm.; zygomatic breadth 325 ; 



♦ Length measured on either side from the antero-lateral protuberancea 

 to the lambdoid ridge ; breadth above the zygoma-roots. 



