July 26, 1901.] 



SCIENCE. 



153 



the folio sheets of the geological map (1:25,000) 

 of Prussia and the Thuriugiau states, with ex- 

 planatory texts. Several sheets of the area 

 north of Berlin may be cited. In the neigh- 

 borhood of Oderberg (46th Lieferung), the 

 Oder turns shai-ply from the ancient westward 

 waterway along the glacial margin past the 

 site of Hamburg to the North Sea, into its 

 present northward course i)ast the site of Stet- 

 tin to the Baltic. Hereabouts are several 

 looped moi'aines with uneven hills and hollows, 

 holding many pools and ponds ; the loops are 

 nicely marked by boulder belts, which have 

 long furnished material for road-making. Out- 

 side of the moraiuic loops (southwest), stretch 

 outwashed sand plains, the barren ' upper 

 sands,' with deep-lying ground water. Inside 

 of the moraines come the rolling uplands of the 

 ground moraine, with a fertile soil. Overlaid 

 sands and silts are common here, the deposits of 

 ice-margin lakes held in the loops during glacial 

 retreat ; the outlets of the lakes are frequently 

 found in trenches through the morainic hills. 

 Some of the larger existing lakes of the district 

 remain in shallow basins, roughly central to 

 the morainic loops. 



South of the outwashed sand plains, the 

 broad channel of the ancient waterway (the 

 Thorn-Eberwalder channel, the northern of the 

 three chief ice-margin waterways) is strewn 

 with the ' valley sands. ' Once as smooth as 

 the bed of a large river may be, these sands are 

 now trenched and terraced to moderate depths 

 west of Oderberg, where they are traversed 

 only by small streams ; but they are largely 

 swept away southeast of Oderberg, where the 

 ice-margin river sank to a lower level when 

 the northern outlet past Stettin was opened. 

 A new, broad channel was eroded at the lower 

 level, with great sweeping curves appropriate 

 to the course of a large river ; the channel bed 

 now remains as a marshy alluvial plain on 

 which the diminished Oder wanders. One of 

 the great curves of the channel rounds a spur 

 of drift uplands by Oderberg ; the ' new 

 Oder ' is led through the narrow neck of the 

 spur by an artificial canal, while the ^ ' old 

 Oder ' still straggles around the spur. 



Where the ancient waterway departed some- 

 what from the moraines, a low upland slopes 



southward to it from the moraiuic loops and 

 their sand plains. The upland here is a gently 

 rolling drift plain, traversed now and again by 

 the sandy beds of larger or smaller streams 

 that for a time came out from the ice on the 

 north. A striking example of this kind is found 

 near Kyritz (Lieferung, northwest of Berlin). 

 The sandy stream bed was probably washed by 

 sprawling currents in many braided channels, 

 which acted partly as an aggrading agent, for 

 the bed is hardly incised beneath the rolling 

 drift plain. Later a narrow trench was cut 

 through it, as if the ice-water had for a brief 

 interval been changed from a turbid sand- 

 bearing stream to a clear stream (perhaps the 

 outflow of an ice-margin lake) ; the trench is 

 now floored with peat, or occupied by long 

 shallow lakes, as if it were barred here and 

 there with in washed alluviurn. 



The casual traveller often describes the 

 north German lowlands as a ' flat and unin- 

 teresting country.' It is as meaningless to 

 him as a cuneiform inscription would be ; yet 

 how significant its delicate details become when 

 interpreted ! To American students, the elab- 

 orate treatment of this remarkable field fore- 

 shadows what may in time be provided for us 

 concerning the Illinois and other glacial lobes, 

 whose general features only have now been 

 sketched. 



W. M. Davis. 



MUSEUM REPORTS. 



The ' Annual Report of the Director ' of the 

 Carnegie Museum for the year ending March 

 31, 1901, was issued a short time ago, as well as 

 the report on the ' Prize Essay Contest.' From 

 the report we learn of the rapid progress of the 

 institution particularly in the field of vertebrate 

 paleontology, the explorations conducted last 

 year by Mr. J. B. Hatcher having resulted in 

 the acquisition of nearly 200 boxes of speci- 

 mens, some of the more notable of which were 

 described a short time ago in Science. As 

 Mr. Hatcher again began field work in April, 

 the present year will doubtless see other im- 

 portant accessions of fossils. 



In zoology the announcement is made that the 

 Museum has acquired a specimen of the almost 

 extinct Rhinoceros simiis, only four other ex- 



