45 
proceed in darkness. Detmer adds a few historical references, viz, 
-Humboldt (1794), according to whom seeds sprout more easily in 
darkness than in light; Fleischer (1851), Heiden (1859), and Nobbe 
(who all consider solar rays as having no action on the seeds), and, 
finally, Hunt (1851), who considers that ight retards germination. 
After this preliminary historical survey, Pauchon communicates 
the results of his own experiments as to the influence of light on ger- 
mination on the following twenty-two species of plants: . 
Cruciferve : Leguminoser : 
Brassica napus. Arachis hypogiea. 
Iberis amara. Dolichos lablab. 
Lepidiuin sativum. Rubiacere : 
Sinapis alba. Coffea arabica var. Rio. 
Raphanus sativus. Spilanthes fusea. 
Ranunculacer : Helianthus annuus. 
Delphinium Consolida. Carthamus tinctorius. 
Nigella sativa. Malvacer : 
Cucurbitacer : Hibiscus escuientus. 
Cucurbita melo var. melon Polygonacere : 
vert. Fagopyrum esculentum. 
-apaveraceee : Linacee : 
Papaver somniferum. Linum usitatissimum. 
Eupherbiacere : Bignoniacez or Pedaliacee : 
Ricinus communis. Sesamum orientale. 
Gramine : Liliaces : 
Zea mays. Pancratium maritimum. 
After deducting doubtful results or failures Pauchon gives the 
following conclusions (see p. 131 of his work above quoted) : 
(1) In 22 experiments germination occurred first in the light; in 
26 experiments it occurred first in the dark. 
(2) Five times we obtained duplicate results favorable to the 
light for the same species of plants (Arachis, Zea mays, Dolichos, 
Sinapis, and Linum). Eight times these duplicate results were 
favorable to specimens kept in the dark (/Telianthus, Delphininm, 
Pancratium, Ricinus, and Papaver). In one case (Linum) two re- 
sults were obtained favoring hight and two favoring darkness. 
(3) Among the 22 species of plants used in the experiments 14 gave 
mixed results equally favorable whether placed in the light or the 
dark. 
(4) Among the 8 other varieties only 1 gave negative results (Cof- 
fea); 3 gave results favorable to light (Cucurbita, Spilanthes, and 
Carthamus) ; 4 gave results favorable to darkness (Delphiniwm, Pan- 
cratium, Lepidium, and Nigella). 
It appeared to Pauchon impossible to draw any conclusion what- 
ever from these facts. Should we be astonished at this? The prob- 
lem is certainly much more complex than appears at first sight. 
