Me Gee and Call — Loss of Des Moines, Iowa. 211 



torn of the cistern) are rounded, and vary from one to six 

 inches in diameter. They are sometimes composed of fine sand, 

 either massive or laminated, again of uniformly coarse sand or 

 fine gravel, and at other times of a mixture of all. The two 

 largest are lenticular in cross-section, each about two feet long 

 and eight inches thick; one consisting of fine laminated sand, 

 and the other of coarse ferruginous gravel. None of these 

 pebbles, except the last mentioned, are at all cemented. About 

 eight feet from the surface is a distinct dark-brown ferruginous 

 band one or two inches thick, above which the drift 

 yellow and free from cylindrical ferruginous 

 Below it is quite blue and abounds in the ferrngii 

 tions for three feet, then irregularly mottled and with 

 cretions for two feet, while for the last part it is again brownish- 

 yellow and without the concretions. The fossils occur only 

 near the base associated with smoothed pebbles, sand-pebbles, 

 loss-kmdchen, and tubelets, and are mainly fragmentary. The 

 following species, in addition to many indeterminate fragments, 

 were observed : — 

 Succinea obliqua Sar. 

 Succinea avara Say. 



The excavation was examined while in progress, and im- 

 mediately after completion. Erratic bowlders up to five feet 

 in diameter were exposed in contiguous street cuttings. 

 Throughout the drift presents a loss-like aspect in color, con- 

 stitution and structure. On exposure it hardens exteriorly and 

 yields a calcareous efflorescence. 



1. — Brownish-yellow drift clay c 



and a few local |>.1>M>- and hr»wlder>. Fifteen (?) feet. 

 2. — Loss, light butt", containing losx-kindcheii, tnbek-ts, and the 



following fossils : 

 Sur,>u)<-„ obliqua Say. J 



Limnophysa hum His Say. 

 3.— Irregularly stratified gravel, sand and pebbly drift clay, 

 brownish-yellow. Two feet. 

 The section was based on the materials thrown from a well 

 just completed and walled, the sequence being determined by 

 the arrangement, and the thickness of each member estimated 

 from the amount of such material in the annular heap surround- 

 ing the well. It supplements the adjacent section 6 in show- 

 ing that on this plateau the drift is unquestionably underlain ( 



