GEOLOGY: R. W. SAYLES 
167 
great, as is shown by the checking measurements made on both nega- 
tives between the points indicated by Hnes ^'A" and ^'B." The ratio 
of negative number 2 (the one made six months later than the other) 
to negative number 1, as shown by measurement "A" on both nega- 
tives is 1.338 =t 0.002. The ratio of negative 2 to negative 1, as shown 
by measurement ''B'' on both negatives, is 1.339 0.002. 
The following results were obtained by measurements of areas num- 
bered 1,2, and 3 on Plate I. 
Results of Measurement of Alhinistic Areas^ 
Area 
Measurement 
Per cent of 
increase 
Per cent of 
decrease 
Per cent of 
error 
1 
c 
6.5 
^ .9 
2 
D 
3.5 
=»= .5 
3 
E 
4.0 
±1.0 
1 
F 
1.0 
=tl.0 
These results proclaim that the albinistic areas extended their bor- 
ders, as shown by measurements ''D" on area number 2, ''E" on area 
number 3, and "F^' on area number 1. The results also proclaim that 
the process of pigment metabolism was revived in area number 1, as 
shown by measurement *'C," where the decrease of the size of the area 
was 6.5 per cent of its total height (vertical measurement of the body) 
with a possible error of ±0.9%. 
' Amer. Anthrop., New York, N. S., 16, 222-237 (1914). 
^Ibid.,p.23A. ^ Ibid., p. 235. 
^ Ibid., p. 233. ^ Ibid., p. 234. 
8 Number 32 of the Genealogical Chart, Fig. 74, p. 222 of Op. Cit. 
^ Mr. Wilcox is recognized as a most careful expert in the field of stellar photographic 
measurements. 
' A detailed histological study of the skin of this person may be found in the article 
referred to in footnote number 1. 
BANDED GLACIAL SLATES OF PERMO-CARBONIFEROUS AGE, 
SHOWING POSSIBLE SEASONAL VARIATIONS 
IN DEPOSITION 
By Robert W. Sayles 
UNIVERSITY MUSEUM. HARVARD UNIVERSITY 
Received by the Academy, January 26. 1916 
Near Boston, on the peninsula of Squantum, facing Quincy Bay, is a 
formation of tillite of Permo-Carboniferous age, described in 1914.^ 
Lying conformably on the tillite is a slate formation with a known 
thickness of about 800 feet. 
