ii8 



Field Columbian Museum — -Zoology, Vol. i. 



times as many as a dozen are found together, being in this 

 respect quite different from either Swayne's or PhiUip's, of which 

 rarely more than three are started at a time. It may, however, 

 have been possible that as it was the summer months, April to 

 October, when I was in Somali-land, that these animals were 

 paired and that would account for only a male and female being 

 always found alone together. In its general habits Guenther's 

 Dik-Dik does not seem to differ from its allies of the same genus. 

 The skull shown on the plate accompanying this paper will give 

 a very clear idea of the great difference in outline there is between 

 it and those of the shorter nose species, while the lengthened 

 premaxilla- with their peculiar shape at once attract attention. 

 This species is about one-fourth larger than Phillip's Dik-Dik. 

 The skull is very high posteriorly at about the center of the 

 parietal, from which point it descends abruptly to the supra- 

 occipital and gradually forward to tip of nasals. It is wide 

 between the orbits, narrowing slightly to the nasals. These last 

 are very short, being wider than they are long. The premaxillae 

 are very long and slender, depressed anteriorly, and, at about 

 their midlength, rising with a sharp curve to the nasals, affording 

 a receptacle for the proboscis-like nose. Lacrxmal fossa very 

 large and deep, occupying all the lacrymal and extending onto 

 the maxilla. Z3'goma, short, composed mainly of a process 

 from the squamosal overlapping a short process from the molar. 

 Glenoid fossa, deep. Palatines short, median portion not pro- 

 duced beyond posterior end of second upper molar. Pterygoids 

 short and narrow. Occipital process short and slender, auditory 

 bullae large. 



INCHES 

 Total length of skull 4.20 



Fronto-parietal suture to tip of premaxilla; 3 



Anterior edge of orbit " " 2 



Length of nasals 



" " premaxilhe i 



Width of skull at posterior edge of orbits 2 



" " " " anterior " " " 



Extent of uj^per premolars 



" " " molars 



'• " lower premolars 



" " " molars 



" " diastema of lower jaw 



20 

 00 

 40 

 55 

 05 

 45 

 60 



75 

 55 

 So 



65 



