° f é . 9 
290 The American Geologist. Mat, ne 
The schists occur in a narrow belt extending southeast 
through the pass. Low hills near Verdemont station are com- 
posed of the dark gray mica schist, and a line of low hills 
standing in the valley seems to carry the belt nearly to San 
Bernardino. This schist belt is a fragment of some sedimen- 
tary series surrounded and intruded by the Mesozoic granites. 
Its correlation remains one of the unsolved problems of that 
interesting region. I will suggest that it may finally prove 
to be a portion of the San Emedio series. 
CONCLUSION. 
It is evident by this time that the rugged mountains and 
desert plains of Southern California contain a considerable 
variety of old crystalline formations and that it promises to 
prove a splendid field for the student of pre-Paleozoic geology. 
It binds the Archean continent of the Interior Basin region to 
the ancient land mass which, it is presumed, occupied the site 
of the present Coast ranges. In its Mesozoic granites, it con- 
tains the key to the relation between the Jurassic rocks of the 
Sierra Nevada region and the Franciscan series of the Coast 
ranges. It is an extensive region—‘a land of magnificent dis- 
tances,” as a miner paraphrased. The few weeks which I 
have spent in it scarcely resulted in what deserves to he called 
a beginning of the elucidation of its geology. 
Berkeley, Calif., March 4, 1902. 
PALAEONTOLOGICAL SPECULATIONS. 
By L. P. GrRaTacapPp, New York. 
Due 
Formal Tendency. 
Something very like tendency, direction, appears in a re- 
view of a large number of fossil forms where there is discov- 
erable any change at all in structure or shape or size. Take a 
strict and definite case of evolutional change and it exhibits a 
procession of forms in which some structural feature appears 
more and more developed until it assumes extravagant propor- 
tions, or inversely displays diminishing importance, until it 
is obliterated. 
age ‘ell . 
