102 EINAR LONNBERG, BIAMMALS COLLECTED BY THE SWEDISH ZOOLOGICAL EXPEDITION ETC. 



A series of eleven specimens from this locality display a rather great variation 

 with regard to colour as well. The young are, of course, black, but the adult have 

 sometimes hardly any black at all on the head, and sometimes an old specimen with 

 well developed crests on the skull has the entire head black. There is also a nearly 

 albinistic specimen in the collection. This one is whitish ash-coloured with pale 

 huffish tips to some of the hairs. 



Around Meru boma these Mole-rats were very common in the shambas. 



Bathyergidae. 



Heterocephalus glaber progrediens n. sp. 



This peculiar Naked Rat was observed in the thornbush country north of Guaso 

 Nyiri, and four specimens were captured. When one sees this quaint and naked being 

 the first impression is that it is the newborn young of some large rodent. The 

 nakedness, blindness, comparatively small feet but big head make it look like a foetus. 

 But the ferociousness with which it at once bites anybody or anything that touches 

 it, soon takes away the belief in its youth and harmlessness. It lives entirely under 

 the ground, and its burrows appear to be long but mostly situated rather near the 

 surface. Here and there the burrow has openings through which the earth is thrown 

 out rapidly in thin squirts. The result of this is small hills which Drake-Brockman 

 very properly with regard to their appearance compares with » miniature volcanoes >. 

 Often quite a number of such little hills are situated near each other in rows along 

 the burrows. It appears most probable that the animals do most of the digging 

 with their powerful incisors as the feet look very weak. The throwing out of the 

 earth is of course effected with the hind feet, which are especially adapted for that. 

 The outer appearance of these peculiar animals has been repeatedly described by 

 RtjppEL,® Oldfield Thomas,^ Paroka & Cattaneo* etc. 



One of my specimens is figured PI. Ill, fig. 2, and the head of the same, a 

 little enlarged, is seen on the same plate fig. 3 from its anterior end. These two 

 figures show the arrangement of the hair and bristles on the head and body, while 

 the peculiar fringes on the feet are elucidated by fig. 4 which shows a hind foot 

 seen from above, twice enlarged. 



In the interior of the mouth as well some scattered bristle-like hairs are found 

 on the insides of the cheeks in front of the molars as may be seen on PI. Ill, fig. 5. 

 In this figure as well the structure of the palate is shown. It differs from that of 

 Fornarina phillipsi Thomas in having only two pair of palate-ridges, the anterior 

 pair of which is confluent, while Fornarina to judge from the figure communicated 

 by Thomas (1. c. PI. LIV, fig. 2) has four. 



1 The Mammals of Somaliland, London 1910, p. 137. 



^ Mus. Senckenb. Abh., Ed. Ill, Frankfurt 1845, p. 99—101. 



' Proc. Zool. Soc. London 1885, p. 845—849. 



* Ann. Mus. Civ. Genoa, Ser. 2, Vol. XIIT, p. 419—445. 



