256 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



were of full average width. Etiolated leaves of Tritelia or Milla 

 were two or three times the length of organs grown in light, and also 

 showed a slight increase in width. The curvatures and torsions 

 present, to some extent, in green leaves were accentuated in etiolated 

 organs, becoming most pronounced as maturity was reached and 

 death set in. The two species of Tulifa examined developed leaves, 

 the margins of which had inrolled margins and marked torsions were 

 shown. No comparative measurements were made, but an inspec- 

 tion of the etiolated leaves suggests that an abnormally large size 

 was reached. Stomata were seen in etiolated leaves of Allmnt^ 

 ApIectriDii, Hyacinthus, T?'is, JVarcissus, Ttpularia, Tritelia and 

 Tulipa. It may be said that leaves of the above species arising 

 from subterranean bulbs or stems attained normal or supra-normal 

 dimensions with open, and probably functional, stomata in all in- 

 stances, although this last statement does not rest upon exact obser- 

 vation, and have a duration fairly equal to that of the normal under 

 ordinary circumstances. The normal green leaf would doubtless 

 prove more resistant under unfavorable circumstances and under 

 prolonged seasonable conditions would live longer than etiolated 

 leaves. The fact stands out prominently that torsions and curva- 

 tures naturally present in some species are accentuated, and are also 

 shown by species not usually exhibiting such phenomena. The 

 positions assumed by many etiolated leaves of this group are due in 

 greater part to the direct action of curvatures and torsions arising 

 autotropically rather than to any positive reflexive action. Leaves 

 of Apl€ct?-uni, Bozuica, Caiiuissia, Hyacinthus and h'is^ were held 

 in an erect position until they perished ; although no geotropism was 

 directly demonstrated, yet it seems justifiable to assume the capacity 

 of such reaction. On the other hand, the leaves of Allium^ JVarcis- 

 sns, Ornithogalhim^ Tipulan'a, Tiilipa and Tritelia, were held in 

 various prostrate and decumbent positions. The terminal portions 

 of the leaves of Jiarcissiis and others occasionall}' curved upward. 

 The curvatures and torsions noticeable in some of the leaves, as well 

 as in many etiolated stems, are perhaps due in part to the exagger- 

 ated inequalities of growth consequent upon the prolonged continua- 

 tion of the activity of tissues in an embryonic condition, which permits 

 some, especially parenchymatous tissues, to attain abnormally large 

 volume, thus disturbing the customary mechanical relations of the 

 separate tracts. The proximity of the embryonic cells proper to the 



