Proceedings of Learned Societies. 157 



He pointed out the almost constant presence of silica in the waters of 

 the earth, as enhancing the probability of his views. The tendency to 

 circular or globular arrangements often observed in siliceous minerals 

 was compared by the author to certain minute rings observed to 

 form during the evaporation of an aqueous solution of silica. A 

 second paper relating to silica was also read at the same meeting. 

 In it several springs in New Zealand, very rich in silica and alkaline 

 silicates, were reported on, and the beautiful quartz-sinter described, 

 with which they rapidly incrust surrounding objects, such as leaves, 

 flowers, buds, and fruits. A singular crystallization of large quan- 

 tities of phosphate of lime occurring in cavities in teakwood was 

 also brought under the notice of the Society by Professor Abel. 



EOYAL INSTITUTION".— February 7. 



On the Fossil Remains op Man, by Professor Huxley. — The 

 brain-case of man has many varieties of shape and proportion among 

 the different races of men. 



The skull of a Negro was shown ; its breadth was small in pro- 

 portion to its length — in fact, was only six-tenths of it. The skull 

 of a Turk, on the contrary, was, in breadth, nine-tenths of its length. 

 All skulls come under one or other of these classes. Taking eight- 

 tenths of the length as a standard from which to classify skulls 

 according to the proportion between their length and breadth, all 

 that have for breadth a less proportion than eight-tenths of the 

 length are termed dolichocephalic, or long-headed ; all that have a 

 greater proportion, or even that proportion (eight-tenths), of the 

 length in the breadth, are termed brachy cephalic, or round-headed. 



Skulls which are of the second class generally have the jaws 

 orthognathous — nearly or quite in a perpendicular line with the fore- 

 head. Those of the first class have the jaws prognathous, or more 

 prominent than the forehead. 



If a line be drawn on a map from the centre of Russian Tartary 

 to the Bight of Benin, it will be found that north and east of this 

 line the heads are of the brachycephalic type ; south and west of it 

 they are dolichocephalic ; north and east the faces are orthognathous ; 

 south and west, prognathous. This, however, is a very broad state- 

 ment of fact. Near these points may be found heads of all varieties 

 of breadth ; but, as a rule, the round headed races, Mongols, Tartars, 

 Turks (modified Tartars), are north of this line, and long-headed, 

 Negro races are south and west of it. 



These great changes are doubtless influenced by, and may be, 

 in great measure, caused by difference of physical condition. So 

 great are the differences, that these points may be called the ethno- 

 logical poles. At the northern end are cold, barren, treeless plains; 

 at the southern, the warm, rank fertility of the tropics. As we go 

 away from these ethnological poles, we find, in going from Tartary, 

 the Chinese become longer-headed and more prognathous ; the 

 Grreenlanders are long-headed, so are the Esquimaux, so are the 



