45° Field Columbian Museum— Reports, Vol. i. 



" The steady influx of specimens rendered an increase of space for 

 cases an urgent necessity early in the year, and an extension 30 x 18 

 feet was planned and built over the east gallery adjoining the Cur- 

 ator's office. This was finished and ready for occupancy early in 

 May. It has three large north windows, and accommodates eighteen 

 herbarium cases of the new construction described below, twelve of 

 the old Bebbian cases, two special research tables and a long dis- 

 tributing table as well. The herbarium now has a total of sixty-eight 

 cases, containing in all 1,744 pigeon-holes. Through this enlarge- 

 ment the storage room was freed of much accumulated material, and 

 its space became available for systematic arrangement. This room 

 now contains, besides the mounting table and accessories, a continu- 

 ous rack bearing sixteen large tin cases of fifteen pigeon-holes each 

 for the poisoning and storage of duplicates preparatory to their dis- 

 tribution, and eighteen similar cases of trays for the storage of the 

 larger fruits and seeds pertaining to the herbarium sheets. All of 

 the cases in the herbarium from its inception have been constructed 

 upon a principle that renders them as nearly air-tight as possible. 

 The interiors are so arranged that a two-inch space exists between 

 the face of the pigeon-holes and the door, and a like space between 

 the perpendicular stops at their back and the back of the case itself. 

 By this means internal circulation is complete, and as much insecti- 

 fuge as may be deemed advisable can be thrown through between the 

 stops, where it is retained free of the pigeon-holes at the bottom of 

 the case. Here also all plant detritus automatically collects with the 

 withdrawal and insertion of the plant fascicles as they are used. A 

 half round groove, one-quarter of an inch deep, is run completely 

 around the inner face of the door frame, which fits over a like bead 

 on the inner stop; this renders the cases insect and dust proof. The 

 doors are glass paneled, affording a comprehensive view of the con- 

 tents of each case, thus avoiding the necessity of referring to an 

 index when locating the orders. In the earlier cases two semi-circu- 

 lar spaces were cut from the face edge of the shelves, in order that 

 the fascicles of plants might be readily grasped for withdrawal by one 

 or both hands. This method is, however, open to strong objection, 

 as the frequent grasping of the bundles breaks the plants contained 

 and soils the genus covers as well. In order to avoid this the fol- 

 lowing scheme, converting each pigeon-hole into a drawer, has been 

 adopted : Sheets of heavy straw-board, one inch longer than the 

 depth of the pigeon-holes and slightly narrower, were procured, and 

 a strip of black muslin two inches wide firmly glued on the face of 

 one end. The reverse side was then scored half through one inch 



