24 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 72 



preserved and admirably illustrate the formation of a limestone 

 through the accumulation of this type of animal remains. Material 

 was also secured, both for the exhibition and study series, illustrating 

 the origin of the phosphate beds of the locality through the removal 

 from a phosphatic limestone of the easily soluble calcium carbonate 

 by the leaching power of surface waters. Such material is represented 

 in figure 25 showing a rock outcrop where a porous limestone is over- 

 laid by the contorted and crossbedded rock which upon such leaching 

 gives rise to the phosphate. 



Among the interesting stratigraphic results secured was one show- 

 ing the efficacy of coral reefs of the Ordovician in rock formation. 

 The massive limestone about fifteen feet thick shown in figure 26 

 represents a middle Ordovician formation here containing but a single 

 reef but within a distance of ten miles the number of intercalated coral 

 reefs has so increased that the formation attains a thickness of over 

 250 feet. 



An ancient Indian village near Brentwood, Tennessee, was visited 

 during this trip in the interest of the Bureau of Ethnology. The 

 object of the visit, namely the determination of the length of time 

 since the village was deserted, proved to be, however, outside of the 

 domain of geology. 



Upon the completion of this work Dr. Bassler proceeded to Spring- 

 field, Illinois, where with the permission of Dr. A. R. Crook, Chief 

 of the Museum, he prepared casts of the type specimens of invertebrate 

 fossils contained in the Illinois State Museum collections. The aim 

 in this work is to make the national collections of invertebrate fossils 

 as complete as possible in its representation of type specimens, a 

 work which was further advanced in the early part of January by a 

 visit to the Walker Museum of the University of Chicago, where 

 the casting of all the Paleozoic species which had remained unfinished 

 on the occasion of a former trip was completed. 



Through the courtesy of Mr. E. J. Armstrong, of Erie, Pennsyl- 

 vania, Dr. Bassler was enabled to visit all the classical Silurian and 

 Devonian localities in northwestern Pennsylvania and western New 

 York during the latter half of September. The object of this trip 

 was to obtain a field knowledge of the detailed geology and to collect 

 carefully selected sets of fossils illustrating the numerous formations 

 of this region. This work was successful and the many large collec- 

 tions of Devonian fossils in the museum hitherto lacking exact strati- 

 graphic data can now be determined and arranged in the detail neces- 

 sary to-day. 



