64 THE NAUTILUS. 



than under the boiling sun. The first stop was made at a point a 

 few miles from the city, where the canal cut through the glacial 

 clay or till. In a small stream by the side of the Santa Fe tracks, 

 the conchologists picked up Vivipara contectoides, Planorbis tricol- 

 vis, Sphcerium stamineium and S. simile, the first named species being 

 very abundant. 



The second stop was made just east of Summit, where the canal 

 cut through blue till, in some places almost as hard as rock. 1 In 

 one corner of the canal at this locality the bank and ground was 

 fairly paved with minute shells perfectly preserved and of a whitish 

 or chalky color. From this spot we collected Bythinella nickli- 

 niana, Amnicola limosa, A. I untried, Cincinnatis cincinnatiensis, 

 Planorbis truncatus !, P. campanulatus, P. deflectus and Vulvaia tri- 

 carinata, the last two species being represented by thousands of in- 

 dividuals. These mollusks are all referable to the Pleistocene 

 deposits; P. truncatus was typical and very rare, as but one speci- 

 men was found. From the Desplaines River Mr. Woodruff col- 

 lected Alasmodonta complanata, A. deltoidea, Anodonta grandis, 

 Li/iiipsllis luteolus and Calyculina truncata, the later very large. 



At Willow Springs, which was the next station, I spent about 

 three-quarters of an hour hunting for Anodonta imbecilis, but only 

 succeeded in finding one half grown specimen. This is the only 

 locality, so far as known, for this species in the Chicago area, and 

 we had entertained high hopes of finding a " colony " of them, but 

 such was not to be. The specimen collected was found in a soft, 

 slimy, black mud, filled with broken bottles, tin cans, etc. Under 

 an old bridge we found Succinea retusa very plentiful. 



A long stop was made at Lemont to enable the palaeontologists 

 to examine the many piles of limestone, which had been blasted from 

 the canal, in search of Niagara fossils. Only a few were found, and 

 those were very imperfect. Some brachiopods, a few mollusks, in- 

 cluding several large Cyrtolites ampUcorne, and an occasional Crin- 

 oid or trilobite was all that rewarded the geologists. The small boy 

 got suddenly rich selling the common Niagara Calymene (C. niap- 

 arensis) at from five to twenty-five cents each, according to quality. 

 No recent mollusks were found. 



At Romeo, Dr. H. N. Lyon and myself walked half a mile north 

 to the Desplaines River, and found a good collecting spot where the 

 river ran over a bed of limestone arranged in ledges, and was quite 



1 See Leverett, Bull. 2, Geol. & N., 16 Surv., Chi. Acad. Sci., p. 49. 



