302 General Notes. [ April, 
make it very unlikely that this low flat was excavated in valley 
drift. At least, if so, the drift must have been of unusually fine 
materials. 
The currents which ees these kame-like ridges at have 
swept toward the Androscoggin valley or away from he 
abruptness with which the ridges end on the north- wk favors 
the latter theory, though this could not be confirmed by lines of 
stratification, as no fresh exposures could be found. At Shel- 
burne the valley of the Androscoggin abruptly widens, and there 
has evidently been a lateral sweep of the currents, but I nowhere 
in the valley saw these oblique ridges actually turning back 
toward the west unless it be here at the State line, The appear- 
ances could be accounted for by supposing that during the depo- 
sition of the valley drift, in times of sudden flood, powerful cur- 
rents overflowed into the lateral valley until it was filled with 
water. Coarse materials would be carried for a limited distance 
and the finer would be deposited over that wide interval, which 
would for the time being be a lake. Or it may be that a part of 
these ridges were true kames, deposited in ice channels along the 
flanks of the valley glacier during its final melting. In any case 
it is difficult to see how the currents could have come from the 
north west without leaving some traces of gravel ridges in that 
direction. 
Thus far no decisive evidence can be found that the Androscog- 
gin glacier flowed eastward of West Bethel. Many morainal 
ridges cross the valley but none of them appear to have been 
deposited by the local glacier, unless it be a line of hillocks and 
ridges just west of the valley of the Sunday river, below Bethel. 
A minute examination may show this deposit to be a moraine 
of the Androscoggin glacier.—George H. Stone. 
Marsu on Jurassic DINOSAURIA.—In the Masch, 1880, number 
of the American Fournal of Science and Arts, Prof. Marsh gives 
an account of the Dinosaurian Stegosaurus ungulatus, of which he 
as come into possession of an unusually complete skeleton. He 
finds the genus to be possessed of very distinctive characters, 
which are as follows: 
“(1.) All the bones of the skeleton are solid ; (2.) The femur is 
without a third trochanter ; (3.) The crest on ‘the outer condyle 
of the femur which in birds separates the heads of the tibia and 
fibula, is rudimentary or wanting; (4.) The tibia is firmly codssi- 
fied with the proximal tarsals; (5.) The fibula has the larger 
extremity below.” Prof. Marsh abandons the order Stegosauria 
which he formerly proposed, and refers the genus to the Dino- 
sauria, to a special group. Stegosaurus ungulatus was thirty feet 
long, and walked on its hind limbs; its back was protected by 
bony scuta, and its food was probably vegetable. 
ARCHOPTERYX.—In 1863 M. Haberlein discovered in the litho- 
graphic stone of Solenhofen (Bavaria) a fossil bird, the Archzop- 
