IOWA ACADEMY OP SCIENCES. 
197 
Muhlenbergia. 
39. M. mexicana (L.) Trin. Damp, usually shady situ- 
ations; common. 
40. M. racemosa (Michx.) B. S. P. {M. glomerata Trin.) 
Moist or sometimes dry, open ground; common. 
41. M. sylvatica Torr. Shady banks; frequent. 
42. M. diffusa Schreb. Dry, mostly shady ground; 
frequent. 
Phleum. 
43. P. 'praiense L. Common. 
Alopeourus. 
44. A. geniculatus L. Low meadows; infrequent. 
Sporobolus. 
45. S. longifolius (Torr.) Wood. Dry prairies; scarce. 
46. S. vaginceflorus (Torr.) Wood. (S', minor Vasey.) 
Frequent in dry, waste places. 
47. S. cuspidatus (Torr.) Wood. Dry, waste or sterile 
ground; common. 
48. S. heterolepis A. Gr. Dry prairies; common. 
CiNNA. 
49. C. arundinacea L. Frequent in damp woods. 
Agrostis. 
50. A. alba L. Abundant in moist meadows. 
51. A, perennans (Walt.) Tuck. Common in woods 
and along streams. 
52. A. hyemalis (Walt.) B. S. P. (A. scahra Willd.) 
Common in fields and waste ground. 
Calamagrostis. 
53. C. canadensis (Michx.) Beauv. Wet meadows and 
swamps; common. 
Spartina. 
54. S. cynosuroides (L.) Willd. Common in swamps 
and wet meadows. 
Bouteloua. 
55. B. hirsuta Lag. Frequent on dry, sterile knolls. 
