50 REPORT OF NATIONAL MUSEUM, 1910. 
employment on the Geological Survey. Dr. J. E. Pogue, assistant 
curator of mineralogy, completed four studies on Museum material, 
and devoted some time to the examination of calamine crystals from 
Mexico, phlogopite-biotite intergrowths from Ottawa, Canada, and 
certain unusual pseudomorphs of marcasite after pyrrhotite from 
Osnabruck, Prussia. An account of the turquoise was also begun, 
and some work was done on the optical and crystallographic charac- 
ters of carnotite and certain vanadium minerals from Peru. 
Dr. Ray S. Bassler, curator of invertebrate paleontology, finished 
a work which had extended over a period of four or five years on the 
stratigraphy of the Ordovician-rocks of Russia, with a description of 
their bryozoan fauna. He spent two weeks in the Ohio Valley in 
examining the Ordovician and Silurian rocks; and the month of June, 
1910, in a survey of the Silurian and Mississippian rocks in Kentucky 
and Tennessee for the purpose of securing certain geologic data 
needed by the Hon. Frank Springer for the completion of his work 
on the Crinoidea Flexibilia. Reference has already been made to 
the collections obtained from these expeditions. The assistant cura- 
tor, Mr. L. D. Burling, began the study of some Ordovician brachio- 
pods in the collection of the Museum of Comparative Zoology at 
Cambridge; completed his work in connection with the Secretary’s 
monograph of Cambrian brachiopoda, and continued that on the 
Ordovician fauna of Colorado and Wyoming. He has also prepared 
a catalogue of all the Cambrian brachiopoda in the Museum, giving 
complete data for each figured specimen. Dr.. William H. Dall, asso- 
ciate curator, has been engaged in research work on the fossils of the 
Oligocene silex beds of Tampa, Florida, and has nearly completed a 
study of the fossils of the Lake beds of Meteor Crater, Arizona. 
In the division of vertebrate paleontology, Mr. J. W. Gidley, cus- 
todian of mammalian remains, continued his studies of the Fort Union 
fossil mammals, of the skeleton of Basilosaurus (Zeuglodon) now in 
process of mounting, and of Oligocene and Miocene rodents. Mr. 
C. W. Gilmore, custodian of reptilian remains, completed papers on a 
new rhynchocephalian reptile from the Jurassic of Wyoming and a 
new crocodile from the Cretaceous of Kansas. He also devoted con- 
siderable time to a study of the fossil reptiles of the southern coastal 
plain. 
DISTRIBUTION AND EXCHANGE OF SPECIMENS. 
The distribution of regular sets of duplicate specimens during the 
past year was confined almost entirely to invertebrate fossils, of which 
61 sets, containing 3,214 specimens, were sent out. In addition, 
2,732 specimens, of which 1,962 were biological, 752 geological, and 
18 anthropological, were selected from the duplicates to meet special 
applications. To specialists not officially connected with the Museum 
