ADDENDA ET CORRIGENDA 509 



basal and subterminal black patch, the extreme tip white. Chestnuts 

 small, somewhat as in E. grevyi. 



LOG. Mountainous country opposite Tete on the north bank of 

 the Lower Zambesi. 



Differs from all the races of E. burchelli in the presence of a 

 much greater number of principal stripes upon the body and hind- 

 quarters and in the fact that the dorsal extremities of all the body 

 stripes with the exception of the last do not bend obliquely back- 

 wards towards the croup but are approximately at right angles to 

 the spinal stripe. In this particular it resembles both E. grevyi 

 and E. zebra ; but differs from both in that on the croup, the stripes 

 adjacent to the spinal stripe are parallel with it, and point towards 

 the root of the tail, as in Burchelli, instead of being at right angles 

 to it. Hence there is no "gridiron," such as is found in E. zebra; 

 and no trace of the circular or annuliform arrangement of the stripes 

 round the root of the tail which is characteristic of E. grevyi. Also 

 in the size and shape of the head and ears and in general build 

 it approaches E. burchelli much more nearly than E. zebra or 

 E. grevyi. 



P. 76. The pre-orbital pit in the skulls of Quaggas. 

 Mr Pocock (Ann. and Mag. of Natural History, Vol. x., series 7, 

 May, 1905, p. 516) now believes that Sir W. Flower was right in 

 saying that no trace of the pre-orbital depression seen in the skull 

 of Hipparion is to be found [in the adults] of any of the existing 

 species of Equidae. The dissection of the skulls of horses slaughtered 

 in the Garden has shown that the depression is sometimes present 

 but more often absent : it exhibits indeed every gradation between 

 a hollow perceptible to the eye and touch and a perfectly flat bony 

 surface. From this hollow or from the corresponding area of the 

 skull arises a long muscle which passes forwards to supply the upper 

 lip and nose; and he "believes that its sole significance is to give an 

 increase of surface for the attachment of muscular fibres." He 

 therefore thinks that this pit never contained a gland, though the 

 large depression in the skull of Hipparion was probably not for 

 muscular attachment but for a gland as hitherto supposed. Ono- 

 hippidium has a pit even larger than that of Hipparion and it lies 

 higher on the face, in correlation with the extremely elevated 

 fronto-nasal region of the skull, but in two casts of the skull of 

 Onohippidium there may be noticed a little below and in front 

 of the orbit an additional quite shallow depression, forcibly recalling 



