410 Albany Aluseum Ercord^. 



that the species of Homopus are derived from a single stock their 

 fixed characteristics may be taken to indicate the establishment of 

 the species at a distant period, so that their differences have 

 become fixed and intermediate forms have died out ; the many 

 members of the geoniefrica-gron\:> on the other hand would seem 

 to be a more recent series whose specific characters are not yet 

 fully established or in which overlapping forms have not yet 

 disappeared. 



The well defined character of the six species of Himiojniii is 

 further emphasized by their geographical distribution, as each is 

 found to occupy a very distinct area. Ar'fiolafiift is known from 

 the Districts of Albany, Alexandria, Uitenhage, Cape Town, and 

 Malmesbury, and probably occurs along the whole extent of the 

 south eastern and south western coasts, extending inland until 

 the higher regions are reached. Femoralh has been obtained 

 from the Districts of Aliwal North, Wodehouse, Cradock, Middle- 

 burg, Hanover, Colesberg, and as far to the north as Barkly West 

 (Warrenton). It thus occupies the north-eastern part of Tape 

 Colony, and very likely will be found extending into the Orange 

 River Colony. BouJengeri so far as established has a well defined 

 distribution south of this in the adjacent Districts of Willowmore, 

 Aberdeen, and Beaufort West, a region included within the Karoo 

 Plain. The single specimen of darli'ngi was found far to the 

 north of the femoralis area, coming from Mashonaland, Rhodesia. 

 Signatus is yet known only from Ookiep, Namaqualand, in the 

 extreme north western part of Cape Colony, while nogueyi comes 

 from Medina, Upper Senegal. 



Though the specimens hitherto received can be considered as 

 only very incompletely representative of the wide area of South 

 Africa, still the results are significant as far as determined. As yet 

 there is no overlapping of one species with another ; no two 

 species have been obtained from any one district. Moreover, the areas 

 indicated above are characterised by distinct geographical and 

 floral features. It is remarkable how closely they conform with 

 the Floral Regions recognised by Dr. H. Bolus in his paper 

 " Sketch of the Floral Regions of South Africa." ' The South 



' Science hi South Africa, Capetown, 1905. 



