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IOWA ACADEMY OF SCIENCE 
in this respect : Some ha,v-e inflated perigynia which enable them to float, 
and they are thus carried by streams and by the action of waves for 
long distances. Other water or swamp inhabitants have no* specialized 
structure for seed dispersal, but are doubtless carried over great dis- 
tances in the mud which adheres to the feet of migratory water fowls 
and other animals. Some of the; sedges are able to pass through the 
alimentary canal of herbiverous animals, being protected by their thick 
walled, closed achene, and are probably distributed in this way. This 
possibly throws some light on the reason for the scattered and sparse 
distribution of many of the xerophytic forms of our meadows. For 
this reason and the fact that they are perennial, they need no highly 
specialized means for seed dispersal; in fact, often the simpler the 
achene the better. 
The collections for the studies were made mostly during June, 1908. 
At this time about 150 specimens were collected, and from them 32 
species identified. The specimens were compared with those of the her- 
barium at the State University of Iowa and the determinations con- 
firmed, reference being also made to the herbarium at Ames. 
The writer feels that this list, while it possibly includes quite as many 
as may be collected at any one time, is necessarily incomplete. Among 
the sedges many species flower only under favorable conditions. Thus 
a complete carex flora may not be observed in any one season. 
Family- Cyperaeeae J. St. ITil. 
Grass like or rush like herbs. Stems (culms) triangular, solid (rarely 
hollow^), quadrangular, terete or flattened, and rather slender. Roots 
fibrous and 1 many species perennial by long rootstocks. Leaves narrow, 
with closed sheathes. Flowers perfect or imperfect, arranged in spike- 
lets, one (rarely 2) in the abdl of each scale, glume or bract, the spike- 
lets solitary or clustered, 1-many-flowiered. Scales two ranked or spir- 
ally imbricated, persistent or deciduous. Perianth hypogynous, com- 
posed of bristles, or inferior scales, rarely calyx-like, or entirely wanting. 
Stamens 1-3, rarely more. Filaments slender or filiform. Anthers two- 
celled. Ovule one, anatropous, erect, in the one-celled ovary. Style 2- 
3 cleft or rarely simple or minutely 2-toothed. Fruit a lenticular plano- 
convex, or trigonous achene. Endosperm mealy, embryo minute. 
About 65 genera and 3,000 species of wide geographic distribution. 
