REPORT OF ASSISTANT DIRECTOR. 51 



and to the development of the sectional library. Very large collections 

 have been made by Mr. A. Schott during the spring and summer months 

 from the parks and gardens of the city. These collections are designed 

 primarily to aid in the preparation of a catalogue of the ornamental plants 

 of Washington, but while serving this purpose they are at the same time 

 valuable accessions to the herbarium and highly useful in connection with 

 the study of fossil plants. In collecting and preserving these specimens, 

 Mr. Schott has shown great industry and skill. In addition to this work 

 Mr. Schott has undertaken the preparation of a check-list of genera 

 from the Genera Plantarum of Bentham and Hooker, of which about 

 half the manuscript was completed at the end of June. The time of 

 the curator was almost exclusively spent in the study and determina- 

 tion of fossil plants collected by himself, and over one hundred species, 

 many of which are new, were identified and will be duly incorporated 

 in the Museum collections. 



18. DIVISION OF GEOLOGY. 



{a) Department of Minerals. 



This department has been under the charge of Prof. F. W. Clarke, 

 assisted by Mr. William S. Yeates. There have been made during the 

 first half of the year 534 entries, representing 2,137 specimens, all of 

 which are new accessions except 138 specimens, which were found in 

 the old collections without evidence of having been previously cata- 

 logued. Eighteen sets of minerals have been sent out as exchanges, 

 comprising about 1,200 specimens, and much valuable material has been 

 obtained in return. This department was represented at New Orleans 

 by collections of the minerals from which are obtained gems and orna- 

 mental stones, and also by a collection of cut and polished stones. 

 These collections attracted the general attention of connoisseurs and 

 visitors to the Exposition. The minerals were classified after Dana's sys- 

 tem and were arranged in seven flat-top table-cases. The gems were dis- 

 played in two cases, the specimens being mounted on white and black 

 velvet pads. This department did not secure a large amount of mate- 

 rial from the New Orleans Exposition, most of the mineral collections 

 on exhibition belonging to private individuals, to whom the agents were 

 responsible for the safe return of their specimens. One-half of the 

 south-west court has been assigned to this department as its exhibition 

 space, and the collections have been removed thither. 



(b) Department of Lithology and Physical Geology. 



The curator, Mr. George P. Merrill, was on duty at the New Orleans 

 Exposition at the beginning of the year, but has nevertheless accom- 

 plished very satisfactory results in the work of reinstalling the collec- 

 tions upon the extended floor- space recently assigned to this depart- 

 ment. Thcopening of the year found the affairs of this department in 



