24 
IOWA ACADEMY OF SCIENCE 
iiec(iuerer' extended the observations of DeCandolle by removing the 
internments sterilizing, and soaking the seeds and keeping them in moist 
cotton. 
Of the 550 species studied by him, belonging to thirty orders of plants, 
the age of seeds varied from 25 to 135 years. The seeds from the 
following years germinated: Acacia bicapsidaris from 1819; Cytisus 
hiflorus of 1822 ; Trifolium arvense of 1838 ; Ervum lens of 1841 ; Doli- 
chos f unarms of 1868 ; Nelumbium codopJiyllum of 1850 ; N. asperifolium 
of 1858 ; N. speciosum of 1888 ; and Lavatera pseudo-alba of 1862. 
None of the old seeds of the following orders germinated, Juncaceae, 
Liliaceae, Clienopodiaceae, Papaveraceae, Caryophyllaceae, or Cucurbi- 
taceae. 
Recently A. J. Ewark^ has published an exhaustive work on the 
longevity of seeds. A large» number were tested and the records of many 
are given. It would seem from the work of Ewart that many seeds 
have a prolonged vitality, some upwards of 50 and 80 years. A few 
of the results of his studies are given here : 
^^Ann. d. Sci. Nat. Bot. IX, 5:193-320. 1907. Compt. Rend. del’Acad. des Sci. 
142:1549. 
^^Proc. Roy. Soc. of Victoria. 21:1 pt. 1, 1. 1898. 
