1892.] SPECIES OF THE HYRACOIDEA. 51 



type specimens of Hemprich and Ehrenberg's species preserved in 

 Berlin. 



Fifthly, a skin of the same species lent me by Canon H. B. Tris- 

 tram of Durham. 



It will be seen therefore that not only is the present series unpre- 

 cedently large in point of numbers, but that it contains the actual 

 specimens referred to by all the chief writers on the subject of recent 

 years, viz. Gray, Blanford, Lataste, and Bocage. 



Of their papers I would call special attention to that by M. Lataste, 

 already briefly referred to, on the skulls and dentitions of the different 

 " subgenera," and especially to his theory that the minute anterior 

 maxillary tooth of the milk-dentition is a milk-canine which does 

 not have a successor. This theory I believe to be perfectly correct, 

 and am most glad to be able independently to confirm Lataste's 

 observation. This tooth appears most certainly to be homologous 

 with the milk-canine of other mammals, even though it is ordinarily 

 situated some way behind the maxillo-premaxillary suture. 



M. Lataste's other work on the group, being in the form of draw- 

 ings and rough notes, I have found it very difficult to utilize, espe- 

 cially as our opinions are naturally very frequently divergent. H, 

 however, I have published any observation which he has previously 

 discovered and recorded, I must ask his pardon and plead as an 

 excuse the very rough character of the notes which he has made. 



The excellent paper by Prof. Barboza du Bocage ^ should also be 

 referred to, as he has given in it not only full and detailed descrip- 

 tions of the three Angolan species, in some ways the most interesting, 

 because the most annectant, of the genus, but he has also given a 

 complete list of all the known species, with notes on their characters 

 and localities. This paper has therefore naturally been of much 

 service to me while going over the same ground. 



To pass now to the subject-matter of this paper. In the first 

 place, it must be admitted that, as pointed out by Lataste, the time- 

 honoured name oiHyrax^ should be superseded by that of Procavia^, 

 earlier by three years than Hyrax. The family name will therefore 

 be ProcaviidcB, but the ordinal or subordinal name will remain 

 Hyracoidea as before, a name of this rank not necessarily being 

 based on that of a constituent genus. " Hyrax " might, however, 

 be adopted as an English vernacular name, the species of Procavia 

 not having as yet one generally and correctly applicable to them. 



Secondly, there arises the important question as to vrhether all th 

 Hyraces should be placed in one genus, or whether " Heterohyrax ' 

 and "■Dendrohyi'ttx," both proposed by Gray and admitted by 

 Lataste and others, should be recognized as distinct genera or sub- 

 genera. 



Now on this point I find it very difficult to come to a definite 

 conclusion. "Within the group there are two extremes, typified, for 

 example, by P. abyssinica and P. dorsalis — the former with their 



1 J. Sci. Lisb. (2) iii. pp. 186-196 (1889). 

 ^ Herm. Tab. Aff. Anim. p. 115 (1783). 

 3 Storr, Prodr. Syst. Mamm. p. 39 (1780). 



