prove of interest in this connection. The Lookout just west of 

 the Laboratory, and the hill just north of Miller's Bay, are very 

 similar in exposure, soil, and general aspect of the flora, and are 

 separated by a comparatively short distance. The total number of 

 species of vascular plants collected in these localities is 135. Of 

 these 99 were found on the Lookout, and 90 on the hills north of 

 the Bay. The number of species common to both localities is 54, 

 thus leaving 45 additional species for the Lookout, not found on 

 the hill north of the Bay, and 36 in the latter locality not found 

 on the Lookout. Neither of these groups of species found only 

 in one of the two localities reveals or suggests a peculiarity of the 

 locality which might account for the difference. Other restricted 

 localities in this region show entirely different combinations of 

 these species, and the natural conclusion is that the floras of the 

 two localities differ simply because of the accident of distribu- 

 tion which leaves many species of prairie plants in restricted 

 belts and groups. 



A more thorough study of the region will no doubt bring other 

 species to light. The present list includes with few exceptions 

 only the species which were collected, and specimens of which 

 are preserved in the herbarium of the State University of Iowa. 



Tlie Prairie List 



The vascular plants and especially the Spermatopliyta form the bulk of 

 the prairie flora. The Thallopliyta, and the Bryophyta have but scant rep- 

 resentation. 



Subkingdom I THALLOPHYTA 

 A few fungi and lichens occur. The f olloTving have been collected ; fungi 

 marked by an asterisk belong to Mr. Giddings' list: 



Fungi 



* Basidiopliora eiitospora B. & C, on Iva xantliiifolia. 



* Cystapus candidus (Pers.) Lev., on Lepidium apetalum. 



* Peronospora leptosperma DBy., on Artemisia ludoviciana. 



* Peronospora parasitica (Pers.) DBy., on Lepidium apetalum. 

 Erysiplie cichoracearum DC, on Grindelia squarrosa. 



* Claviceps purpurea (Fr.) Tul., on Agropyron Smithii. 



* JEcidium compositarum Mart., on Ambrosia trifida. 



* Mcidium Oenothera Pk., on Oenothera biennis. 



* Phragmidium subcorticium (Schr.) Went., on Posa pratincola. 



* Pucciniu asparagi DC, on Asparagus officinalis. 



* Puccinia caricis Schum., on TJrtica gracilis. 



* Puccinia helianthi S., on Helianthus grossesserratiis, and H. tuterosus. 



* Puccinia menthae Pers., on Monarda mollis. 



* Puccinia silphi S., on SUphium laciniatum. 



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