86 REPORT OF NATIONAL MUSEUM, 1924 



minerals was of chief concern. A study of the chemical composition 

 and optical properties of the mineral copiapite was also completed by 

 Doctor Foshag, and a new mineral, chlorophoenicite, from Franklin 

 Furnace, investigated, its chemical, optical, and crystallographic 

 properties determined. • 



No extensive mineralogical investigations on the collections have 

 been prosecuted by others than the Museum force. As usual, how- 

 ever, numerous calls have been made by members of other depart- 

 ments who have studied the collections and been supplied with 

 material to aid in their own researches. Among outside collab- 

 orators, however, mention may be made of Dr. A. C. Hawkins, who 

 was joint author with Mr. Shannon in the description of canbyite; 

 Dr. Clarence S. Ross, who collaborated in the investigation of 

 iddingsite; and Dr. E. S. Larsen, who has collaborated in several 

 pieces of work. 



Paleontological research has been, as usual, quite actively carried 

 on. Secretary Walcott completed two extended papers on Cambrian 

 stratigraphy and paleontology and with Dr. C. E. Resser has fin- 

 ished the text and illustrations of an article on Nova Zembla fossils. 

 The preparation of a generic work on Cambrian and Ozarkian trilo- 

 bites has also been undertaken, for which numerous pen and ink 

 drawings of the genotypes are being made. Doctor Resser has con- 

 tinued the study of the Wisconsin Cambrian collections with Doctor 

 Ulrich and has forwarded the preparation of his bibliographic in- 

 dex of the Cambrian. In collaboration with Prof. B. F. Howell, 

 of Princeton University, Doctor Resser has undertaken a mono- 

 graphic study of the trilobite family Agnostidae. 



Dr. R. S- Bassler has completed his work on the Recent Bryozoa 

 of the Gulf of Mexico in collaboration with Ferdinand Canu, but the 

 illustrations for this work are as yet unfinished. These two authors 

 have completed and sent to press a report on the Cretaceous Bryozoa 

 of Tennessee. 



Although suffering much inconvenience from illness, Dr. Frank 

 Springer has completed a paper on unusual forms of fossil crinoids 

 and several smaller articles, in addition to continuing his monograph 

 on the Silurian crinoids of the Ohio Valley. 



Dr. E. O. Ulrich has completed a study of an extensive series be- 

 longing to the trilobite family Bathyuridae, and, with Dr. A. F. 

 Foerste and others, has prepared a paper on the stratigraphy and 

 paleontology of northern Michigan. In an endeavor to work out 

 the complicated stratigraphy of eastern Tennessee he has studied the 

 collections from that area. 



Dr. W. H. Dall has completed his studies on some remarkable 

 fresh-water fossils from the Payette formation in Idaho and has 



