1909.] NATURAL SCIENCES OF PHILADELPHIA. 65 



long, root four inches long. March 25 : Roots long and curved about 

 the bottom of the bottles, leaves elongated, dark green, three to four 

 inches long. March 28: Green branches four inches long, leaves flat, 

 roots numerous. April 1 : Two lateral branches green and four inches 

 long. April 5: Shoots eight inches long. April 13: Twig dead. 



(C) March 11: Secondary roots appeared; no bud reaction. March 

 18: Leaf bud burst. March 20: Leaves well expanded, roots well 

 developed. March 25: Leaves advancing rapidly to maturity. 

 March 28: Leafy branches, rapidly growing. April 1, April 5: Growth 

 continued. April 13 : Leaves were sere. 



Tilia Americana. — The chemical solutions used in experimenting 

 with the twigs of the linden were: chromic acid, one per cent, solution; 

 stock picric acid in four times its volume of water; five decigrams of 

 sodium bicarbonate dissolved in fifty cubic centimeters of water; 

 filtered water as a control ; ten drops of hydrochloric acid in fifty cubic 

 centimeters of water; 100 cubic centimeters of ether in 500 cubic 

 centimeters of water; saturated corrosive sublimate in one liter of 

 water. There was no response shown in any of the twigs until March 

 15. The twigs in the chromic acid, ten-drop hydrochloric acid solu- 

 tion and in ether water showed no response during the entire course 

 of the experiments. The record obtained from the other twigs is as 

 follows : 



Picric Acid. — March 15: Bud scales slightly eased apart. March 

 18: Terminal bud burst, three-quarters of an inch, green. March 20: 

 Terminal bud expanded, upper part of the folded leaves seen within. 

 March 25: Terminal bud burst, leaves out of the bud, but folded 

 together. March 28: Leaves brown and nearly dead. April 1 : Twig 

 dead. 



Sodium bicarbonate. — March 15: Inner scales of terminal bud pushed 

 beyond the outer scales one-sixteenth of an inch. March 18: One- 

 fourth of an inch beyond, terminal bud burst, no leaves expanded. 

 March 25, March 28: No further advance. 



Filtered Water (A). — March 15: Two larger bud scales eased apart. 

 March 18: Buds burst, green spire one-fourth of an inch long. March 

 25: Terminal bud green, spire-shaped. March 28: Same condition 

 ;as on previous day. April 1 : No further advance, water later evapo- 

 rates, ending the development of this twig. 



(B) March 15: Terminal bud nearly burst. March 18: Buds ex- 

 panded, three-quarters of an inch green. March 20: Upper buds 

 burst, sides of folded leaves seen. March 25 : Two leaves of the termi- 

 5 



