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•20 THE VOYAGE OF H.M.S. CHALLENGEE. 
wore in course of being ossified, and these skulls were of more advanced age. In C a 
well-marked triquetral bone formed the superior angle of the occipital squama, and a 
large Wormian bone was in the right pterion. In none did the temporal squama articulate 
with the frontal, or was the frontal suture persistent. In all the os planum of the 
ethmoid had a quadrilateral form. In none was the maxillo-premaxillary suture visible on 
the palatal surface. In all the hard palate was hollowed into a deep fossa where the 
posterior palatine foramen opened, and in three of the crania this fossa had a depth of 
15 mm. opposite the second molar. The exoccipitals were tumid on the inferior surface, 
and in B slightly, but in D more definitely, projected downwards, so as to form a short 
paramastoid process. 
The lower jaw of D was a well-developed bone, with a good chin. The angle was 
almost rectangular but not everted, and the teeth were all present. The gonio-symphysial 
length was somewhat greater than the intergonial width. 
The mean cephalic index of the four crania was 7 6 '6 : the maximum (female) was 78, 
the minimum (male) 73. The crania were therefore mesaticephalic, three being above 
its lowest term, but D was dolichocephalic. When D was omitted the mean cephalic 
index of the rest was 77*8. The mean vertical index was 74'4 : the maximum 76, the 
minimum 72*5, both females. The height was somewhat below the mean breadth ; only 
in D, a male, did the height exceed the breadth, and in the undoubted female skull the 
smaller relative height was well marked. In three cases the vertical index was less than 
the cephalic. The skulls were metriocephalic. The mean gnathic index was 96 : the 
maximum (male) 98, the minimum (female) 95. The face was therefore orthognathic. 
The mean facial index was 69 : the maximum (male) 77, the minimum (female) 63. The 
mean nasal index was 44 : the maximum (female) 49, the minimum (male) 41. The 
nose was therefore leptorhine, only one specimen slightly exceeding its highest term. The 
mean orbital index was 93 : the maximum (female) 97, the minimum (male) 87. All the 
skulls were megaseme, except one male, which was mesoseme. The mean palato-maxillaiy 
index was 11 1*5 : the maximum (female) 115, the minimum (male) 109; there was no 
great disproportion between the length and breadth of the palato-alveolar region ; the index 
of which was mesuranic. The mean capacity of the four crania was 1 3 3 3 '5 cubic centimetres ; 
that of the two presumable males was 1376; that of the tw r o presumable females 
1291 c.c. The two males were mesocephalic, whilst the average of the females, as 
well as that of the series of four skulls, was microcephalic. 
These Fuegian crania were therefore on the average mesaticephalic, metriocephalic, 
tending to phsenozygous, orthognathic, leptorhine, megaseme, mesuranic and microcephalic. 
Patagonian. — The single skull marked Patagonian was an adult male. It corresponded 
in general form with the Fuegian A. It had the same cephalic index 77*5, and was there- 
fore mesaticephalic. Its vertical index, greater than in A, and almost as high as its 
