15 
such criteria as ones of "geographical coincidence." I have limited 
the inclusion of materials in this part of the collection, as in the 
whole collection, to those I am confident were included in the 1857 
bequest. 
I have prepared several indices to the Bailey Collection. The 
taxa index includes all generic and species names of diatoms l) recorded 
on the slides, in the Catalogue of the Bailey Microscopical Collection 
and in the paleographs, 2) noted on sheets of exsiccati, not just the 
original names applied by the collectors, and 3) listed in the Catalogue 
of the Unmounted Materials [of the] Bailey Collection for which there 
are extant materials in the collection at the Farlow Herbarium. The 
geographical and person's indices cover also all appropriate names used 
in the three major parts of the collection, plus a few I have added to 
facilitate access to selected materials. 
