M. L. TiLDESLEY 
177 
Although our material, when divided up into sexes and groups, is far from ample 
enough to allow us to form decisive conclusions as to the racial constants, and as to 
the exact relation in which the Burman race stands to other types, it is still by far 
the largest collection of Burmese skulls yet submitted to craniometrical methods, 
and until a fuller series shall be available to supplement these, a preliminary study 
of the type by computing means only will not be labour spent in vain. 
2. Measurements and Methods of Measurement. 
The following direct measurements* have been taken : C = capacity taken with 
mustard-seed tightly packed in skull, and then weighed, the worker having pre- 
viously performed this operation on one of the "cranes etalons" described by 
Macdonnell| in order to bring her personal equation into line with that of her pre- 
decessors. The contents of the crane etalon were packed into the measuring glass, 
as well as weighed, and the water capacity was also measured in the glass, in order 
to obtain the constants for the calculation of capacity. F = Flower's ophryo- 
occipital length. L' — glabellar projective horizontal lengthj. L = maximum 
length from glabella to occiput §. B = maximum horizontal breadth on parietal 
bones. B' = least forehead breadth from one temporal crest to the other. H' = 
basio-bregmatic height. H = height measured on craniophor, from basion to the 
point vertically above it (generally a little behind the bregma). OH = auricular 
height, as measured on the craniophor, that is, the height of the skull vertically 
above that part of the auricular orifice which rests on the top edge of the ear-plugs j|. 
LB = length from basion to nasion. Q = transverse arc perpendicular to the hori- 
zontal plane, passing through the "apex," and terminating on both sides at the 
top of the ear-rods, this measurement being taken when the skull is on the cranio- 
phor. In this measurement the tape is carried on to the ear-rods after passing 
over the zygomatic ridges. Q' = a similar measurement taken off the craniophor, 
and terminating at the "auricular points^". <S = sagittal arc from nasion to 
opisthion. S-^ = arc from nasion to bregma. S2 = arc from bregma to lambda. 
= arc from lambda to opisthion. S.^' = chord from lambda to opisthion 
U = horizontal circumference measured directly above the supercihary ridges and 
round the most projecting mesial part of the occiput, i.e. the most projecting part 
between the inion and lambda. PH = premaxillary height, measured from 
alveolar point to the tip of the anterior nasal spine, if such exists, and, where it 
does not, to the sagittal point of the lower edge of the pyriform aperture. G'H = 
upper face height from nasion to alveolar point. GB — face breadth from the lower 
end of one zygomatic-maxillary suture to that of the other, where the suture crosses 
the lower front rim of the cheek-bone. J = zygomatic breadth, from the most 
lateral point of one zygomatic arch to that of the other. NH (R) and NH [L) = nasal 
* Major lengths have been given to the nearest -5 mm., the smaller measurements to the nearest 
•1 mm. 
t Biometrika, Vol. m. p. 203. } Ibid. Vol. i. p. 415. 
§ I have thought it best, on account of a good deal of asymmetry in the series, to take L always in 
the median plane, and consequently it may occasionally be less than U. 
See p. 182. •[ See p. 181 
