192 BRAIN-WEIGHT AND SIZE IN RELATION 



and female brains below 35 oz. or 990 grammes, may be classed as 

 microceplialous ; and all above tbe maxima of the medium male and 

 female brain, viz., 52|- oz. or 1480 grammes, and 47| oz. or 1345 

 grammes, may be ranked as megalocephalous, or great brains. 



Professor Welcker, wbo devoted special attention to tlie whole sub- 

 ject under review, assumes another and simpler test, when he says 

 that skulls of more than 540 to 550 millemetres, or 21-26 to 21 '65 

 inches in circumference — the weight of brain belonging to which is 

 1490 to 1560 grammes (52-5 — 55 oz. avoir.),' — are to be regarded 

 as exceptionally large. But while an excess of horizontal circum- 

 ference may be accepted as indicating good cerebral capacity, it must 

 not be overlooked that the adoption of it as the key to any definite 

 or even approximate brain-weight ignores the important elements of 

 variation involved in the difference between acrocephalic and platyce- 

 phalic head-forms. The volume of brain in Scott, and probably in 

 Shakespeare, appears to have depended more on its elevation than its 

 horizontal expansion. The same was also the case with Byron. The 

 intermastoid arch, measured across the vertex of the skull from the 

 tip of one mastoid process to the other, furnishes an accurate gauge 

 of this development. Of thirteen selected male English skulls in Dr. 

 Davis's collection, the mean of this measurement is 15*1 j and of thirty- 

 nine male and female English skulls, it is only 14'4. Of the whole 

 number of eighty-one English skulls described in the " Thesavirus 

 Craniorum," three exceptionally large ones are^No, 123, that of an 

 an.cient British chief, of fully 6 ft. 2 in. in stature, from the Grims- 

 thorpe Barrow, Yorkshire ; No. 905, a calvarium of great magnitude, 

 very brachycephalic, and with the elevation across the middle of the 

 parietals apparently exaggerated by compression in infancy, from 

 Hythe, Kent; and No. 1029, another male skull, remarkable alike for 

 its size and weight, and with a peculiarity of conformation ascribed 

 by Dr. Davis to synostosis of the coronal suture. The intermastoid 

 arch in those exceptionally large skulls measures respectively 16'0, 

 16-2 and 16-9 ; whereas the same measurement derived from the cast 

 of Scott's head taken after death, yields the extraordinary dimensions 

 of 19 inches.* This last measurement is over the hairy scalp. But 

 after making ample allowance for this, the vertical measurement of 

 the skull and consequently of the brain is remarkable. 



* I am indebted to Dr. J. A. Smith F.S.A., Scot., for this and other measurements of casts 

 of The Bruce, Bums, Scott, &c., not accessible to me. 



