22 



EINAR LONNBERG, MAMMALS COLLECTED IN CENTRAL AFRICA. 



known, does not disagree with the present specimens in any important point, I have 

 used this name for the Chimpanzees of Rutshuru especially as the type locality of cottoni, 

 »Sassa-Fluss, siidostKch des Albert-Edward Sees», is not geographically very distant 



from Rutshuru. 



Cranial dimensions of adult Chimpanzees from Rutshuru. 



Total length of skull .... 

 Occipitonasal length 



Basal length 



Condylobasal length 



Zygomatic breadth 



Least postorbital breadth .... 



Breadth of brain-case 



Breadth across alveoles of canines 



T> » outside oi m' . . . 



Length of palate mesially .... 



» » upper molar series . . . 



» » » true molars . . . 



" » lower molar series . . . 



» » » true molars . . . 



Breadth across orbits 



Least interorbital width 



Height of orbit inside 



Width » » » 



Breadth of jre' 



n:o 70 



197,5 mm 

 151 

 136,6 



150,5 » 



123,5 » 



69,7 

 100 » 



58,4 



54.7 » 

 75,8 



46,3 



31,7 



51,5 



34 (33,4 .) 



98,5 » 



18.8 » 



27.2 » 



32.3 » 



11 » 



n:o 163 



186 mm. 



141,8 » 



131,5 » 



145 » 



131 » 



65 » 



100 » 



65.5 » 



53.6 » 



78.4 » 



43.1 » 



29.5 » 



48.2 » 



31.7 » 

 103,7 » 



19.8 » 

 32 » 

 31 » 



10,8 » 



9 



n:o 160 



184,6 mm, 



139,5 » 



142,3 » 



123,2 » 



69 » 



100 » 



54 » 



58 • 



44,5 » 



30,5 . 



49,5 »' 



32,7 ''■ 



100,1 » 



14,2 » 



37,7 » 



35,5 » 



11,2 » 



9 



n:o 161 



180 mm. 



141 » 



129 » 



144,6 » 



113 » 



C6,6 » 



92.4 » 



50 » 

 51,3 » 



73.7 » 



43.5 » 



30.2 » 



51 » 

 34 » 



94.3 » 

 16 » 



28.8 » 

 32,7 » 



11,2 » 



? 

 n:o 178 



179,5 mm. 



136 » 



125 >. 



141,5 > 



121 > 



67,5 » 



90,5 » 



51 



55 » 



71 » 



39 » 



26.3 » 

 43 » ' 



28.4 » '• 

 90,2 » 

 13 » 

 37,4 » 

 32 » 



9,5 » 



? 

 n:o 181 



189 mm, 



143,5 • 



129 » 



143,5 » 



117,5 » 



71 » 



98,5 » 



51.7 > 

 52,3 » 



71.8 » 

 44,8 » 

 30 » 

 51 » 

 33,7 » 



101 » 



18,3 » 



32,7 » 



32,7 » 



9,8 > 



9 



n:o 224 



177 mn 



134,8 » 

 123,5 

 137,5 



66,5 n 



93,7 » 



51.2 » 



55.3 » 

 69,5 » 



40.1 » 



28.2 » 

 44,8(44) « 



30.1 > 



11,6 



32 » 



33.2 » 



9,7 » 



The measurements recorded above show a very considerable variation chiefly with 

 regard to the orbits, interorbital space and the teeth. 



The shape of the orbits influences the superciliary ridge which in all is very pro- 

 nounced, but with differently arched outline. In the <? n:o 70 (PI. V, fig. 1) it forms an 

 even arch with no concavity above the interorbital space. The $ n:o 181 shows almost 

 the same condition, but in the J* n:o 163 there is a slight depression above the inter- 

 orbital region, or perhaps more correctly the superciliary arch above each orbit is inde- 

 pendently a little more elevated than mesially. In the ? n:o 161 (PI. V, fig. 3) about the 

 same condition prevails, but in the females n:s 178, 224, and 160 (PL V, fig. 4) the arches 

 above the orbits are considerably raised, and in the last the mesial concavity amounts 

 to nearly 4 mm. which does not sound much, but nevertheless gives a quite strikingly 

 different aspect of these skulls, effected by the simultaneous raising of the eyebrow ridges 

 with a mesial concavity between them and the increased height of the orbits. This 

 enlargement of the orbits is, however, only produced by the raising of the superciliary 



ridges, and therefore the upper portion of these orbits looks very shallow. 



j '. 



1 Not counting extra anomalous molar. 



2 Premolars wanting, thus approximately from alveoles. 



