I889.J BOTANICAL GAZETTE. 23 1 



Bulletin 7 of the Cornell Experiment Station. 3 His conclusions as to the 

 relative influence of constant and variable temperature on sprouting 

 seem to us invalid on account of his apparent failure to take account of 

 the limits of temperature for the germination of the various species of 

 seeds used. His conclusions are essentially those of Koppen (1870), and 

 are open to the same objections. They are contradi ted by those of Pe- 

 dersen* who found that when the temperature variations were confined to 

 certain limits the growth seemed to be greater rather than less. His fur- 

 ther experiments, however, showed that the temperature variations as 

 such exercised no influence. 



The most remarkable results are those regarding the influence of the 

 amount of moisture on sprouting. A much larger percentage of se^d 

 germinated when the soil was kept drier than usual in greenhouses. In 

 some cases the difference amounted to nearly fifty per cent The best 

 results were obtained when the soil was kept merely moist. 



The other results regarding the influence of soaking before planting, 

 soil, color, latitude, etc., are unimportant. The conclusions as to influ- 

 ence of weight and light accord with those of other earlier observers. 

 Perhaps the most important feature of the bulletin is the insistence of the 

 author upon the inadequacy both of limited testing and field planting to 

 determine the quality of seeds, points that his researches abundantly 

 confirm. 



OPEN LETTERS. 



Some Nebraska grasses. 



Nebraska furnishes a new locality for two grasses which are at- 

 tributed to the far southwest. Meliea Porteri Scrib., credited from Colo- 

 rado to Arizona, was collected in 1887 at Weeping Water, about thirty- 

 five miles east of here, and within fifteen miles of the Missouri river. The 

 second and more interesting find is Eragrotis pilifera Scheele, at Valen- 

 tine, just west of the 100th meridian and at the extreme northern border 

 of the state. Vasey's catalogue says it belongs down in Texas and Ari- 

 zona. What is it doing way up here ? E. pilifera seems more like either 

 Molinia or Catabrosa than Eragrostis. The spikelets are 2-4 flowered. 

 In a three- flowered spikelet, the lower flower is hermaphrodite, the sec- 

 cond male, and the third sterile, with sometimes a pedicel projecting be- 

 yond it. If E. pilifera is to be considered as a true Eragrostis, Molinia 

 should also be made a section of that genus.— Jared G. Smith, Lincoln, 

 Neb. 



3 Bailey, L. H.-On the influence of certain conditions upon the sprouting of seeds. 

 PP. 31-71, figs. 7. Ithaca, the University, July, 1889. 



4 Arbeiten bot. Inst. Wiirzburg, i. 563. 



