yd The American Geologist. August, i904. 
been indicated from the earliest times, since the ranges which are ori- 
ented in the Sinian direction approach one another at their northern and 
southern limits. 
2. The ancient Paleozoic cover resting upon the eroded basement 
lies horizontal and apparently un'jroken in the Lcna-Oleiick country ; 
the Triassic occurring in higher latitudes, and the Upper Jurassic trans- 
gression stretching from here to the latitude of Jakutsk (Yakutsk), 
have the same position. The remaining portion of the entire region 
is divided into two portions by the T>siii-Iing range and its imaginary 
eastern continuation. North of this hne the sediment plateau has 
suffered no foldings, or at most very slight ones of the nature of bov.-- 
ings-up, described by Suess as back-folds (Riickfaltungen) which are 
locally restricted. On the other hand it is broken into horizontal lying 
or gently inclined por^ons displaced in reference to one another ; m 
part these have the form of irregular blocks and SchoUen, as in Schaii- 
tiing (Shan-tung) ; in part they appear in long parallel strips, as in the 
north Chinese and Daurian ranges. The faults appear in part in the 
form of flexures. To the south of the Tsin-ling zone this plateau is 
di^■ided first into crowded, farther away into broad, open folds, with 
abundant superimposition of middle and upper Paleozoic, as well as in 
places of old Mesozoic marine bees, in vhich the Sinian strike controls 
the character of the landscape. 
b. The collective arrangement of the system of faults is independent 
of the internal structure. This is different in the different land-steps 
enclosed by the individual crescents — its fundamental lines may be 
grouped together as follows : 
I and 2. Yunnan (Yunnan) crescent and K-wci (Kui) crescent sur- 
round the horst-like massif of yuiiiian (Yunnan) and Kzi'iu-tschou 
(kui-chau). Much fractured (Vcrkarstctcr) limestone predominates in 
it ; but the mountain structure is not known. The meridional arrange- 
ment of individual form elements in eastern Yunnan (Yunnan) allows 
the presumption of the step-like sinking inward to the east. Farther 
to the north the Hukzcang fault encloses as a part of the Kzcci (Kui) 
crescent the eastern range of the Ta-ta-schan in the Sinian direction, 
which is here moderately folded to the southeast. It is probable that this 
folding continues in the horst of Kzvei-tschou (Kui-chau). 
3. In the step-province enclosed by the Honan crescent the main 
range of the Tsin-ling protrudes as a massive range, strongly folded, 
distinguished by southerly directed compression and over-turning, and 
controlled by the strike direction W. by N. W. — E. by S. E. It is ac- 
companied in the north by similarly directed, partly low. partly very 
high, mountain ranges, which have not been subjected to folding since 
the Cambrian. Zonal sinkings-in may be distinctly made out in the 
northerly inclined orographic blocks arranged along parallel faults. The 
Honan fault cuts off the entire complex upon the east. 
4. The crescent of the Tai-hang-schan (Tai-hang mountains) bor- 
ders a Carboniferous plateau which owes its origin to a relatively deep 
and very uniform depression of the district as a whole. The plateau 
