ON THE GEOLOGY OF THE ISLAND OF AQUIDNECK. 751 
one effect of this lowering, retardation or degradation is the pro- 
duction of the male rather than the female sex. Some facts, at 
= least, in the animal kingdom, as we have seen, support the same 
= view; but to give a statement of this kind the form and validity 
of a law would require a much more extensive survey of corre- 
lated facts. At all events, we do not find the frequent superiority 
of the masculine sex in certain particulars in the higher ani- 
mals necessarily incompatible with this; since this superiority 
prevails usually in apparatus not of the functions of the vegetative 
or organic life, but of animal life or of relation; as of intellection, 
motor power and voice. Beauty of plumage in birds, while we 
naturally attribute to it a certain superiority, may not, in the sci- 
entific sense, unequivocally have this character. If it should be 
conceded that it has, we must then regard its general predom- 
- inance in males as one of the difficulties in the way, at present, of 
any extended or final generalization upon the subject. (The 
remainder of the paper was occupied with the application of the 
` same course of reasoning to the study of the law of increase of 
human population.) 
a e a E 
ON THE GEOLOGY OF THE ISLAND OF AQUIDNECK 
AND THE NEIGHBORING PARTS OF THE SHQRES 
OF NARRAGANSET BAY. — No. IL.” 
BY PROF. N. S. SHALER. 
-PHYSICAL CONDITIONS or THE CARBONIFEROUS Trwe.—The island 
of Aquidneck is so far separated from the mainland that we cannot 
directly refer by traced contact any of its rocks to the masses of 
the shore. It is not difficult, however, to find a dating point in the 
Materials of the island itself. The extensive coal deposits with 
r abundant carboniferous fossils make us reasonably sure that : 
a large part of the island is composed of rocks which were laid 
down at the time when the great coal fields of other parts of the 
continent were being formed. As the rocks of this part of the 
an those of any other part 
to those which cannot be so readily placed in their proper po- 
ions in the succession of deposits. , 
