MISSOURI BOTANICAL GARDEN BULLETIN 21 
have generously deposited in the herbarium collections of 
especial interest. In liew of field work the main efforts of the 
small herbarium staff have been concentrated on the mount- 
ing, distribution, and more complete organization of material 
already on hand. 
Exchanges—Through exchanges with individual botanists 
and institutions a number of important series of herbarium 
specimens have been acquired. A limited number of dupli- 
cates has been sent to correspondents during the past year; 
but a distribution of several thousand duplicates will be made 
during the coming spring season. 
Use of the Herbarium by Outside Botanists —Botanists 
from various parts of the country have visited the herbarium 
in about the same number as in 1920; and every facility pos- 
sible has been extended to these specialists. Dr. Norma E. 
Pfeiffer again spent some time at the Garden during the early 
summer in continuance of her monographiec study of Jsoetes. 
This work has been completed and the monograph is prac- 
tically ready for the printer. Incidentally it may be said 
that domestic and foreign correspondents have responded 
generously in supplying material of certain exotic and rare 
species of this very interesting group of plants. A compara- 
tively small number of large loans has been made during the 
year, but several small loans have been made to American 
specialists. These loans have resulted in all cases in a de- 
cided mutual advantage to both parties concerned. 
Statistical Summary (For the year ending December 31, 1921: 
Number of specimens received on new accessions: 
BY) PUTCHABO carci ies aha tetetee oeare 3,402 
ee eect ae eae ees 1,506 
DyAeXChan gies. temo stn a eee 4,194 
BTN Ee ee phic ee ca A ea sae anche reyasauatets 9,102 valued at $910.20 
Number of specimens mounted and 
INGOTNOLALCO! 2 os we cae sw stinks cuniereis 24,513 valued at 4,902.60 
Number of specimens discarded from 
the NSErbanium=< csc c sc sa cts as ss oa. 29 
Number of specimens in organized 
MOVDAVIVM) oe eis a fc o aratrieeia ae 886,308 valued at 137,134.90 
Number of specimens in unorganized 
herbarium (estimated) ........... 67,167 valued at 5,373.36 
Wood specimens, etc., supplementing 
iG SNOLrDArlUM sce 6c ees oie eters cee valued at 280.00 
Microscope slides, etc............... valued at 410.00 
BTA UAIUStION ait ears one ow secs rae tote eee $149,011.06 
