Ramaley : SEEDLINGS OF CERTAIN WOODY PLANTS. 76 



The writer is indebted to Mr. D. M. Andrews, of Boulder, 

 Colo., for seedlings of this plant and of Acer glabr ion. 



Robinia pseudacacia LINN. 



The " locust tree" is a native of the middle and southeastern 

 United States. The seeds germinate in about two weeks after 

 planting. 



Seedlings of this plant were studied by Lubbock * and by 

 Flot f but the fact is not stated by these writers that the coty- 

 ledons are at first somewhat narrowly elliptical or obovate and 

 only at a rather late stage become " oblong-oval." The descrip- 

 tions hitherto published have not been accompanied by satis- 

 factory figures. 



RUTACE^E. 

 Ptelea trifoliata LINN. 



This is the so-called " hop tree" of the central United States. 

 The seeds germinate in from three to four weeks, the seed coat 

 remaining underground. Almost as soon as the cotyledons get 

 above ground they become erect and then separate. 



The cotyledons are nearly sessile, elliptical-oblong, entire, 

 6 mm. long and 3 mm. broad. They grow for some time and 

 become at length 18 mm. long, 7 mm. broad, minutely serrate, 

 short-petiolate, with midvein distinct. The hypocot}*! is rather 

 stout, 15-20 mm. long. 



The epicotyl is 20-40 mm. long when the first leaf is fully 

 open. It often elongates somewhat after that time. Leaves 

 are alternate. The first foliage leaf is usually simple, ovate, 

 petiolate, with crenulate margin. Sometimes it is trifoliate, 

 sometimes but partially compound ; perhaps one of the side 

 leaflets is separate, but not the other. The second leaf is 

 usually trifoliate, sometimes incompletely so. Later leaves are 

 all trifoliate, the terminal leaflet larger than the lateral ones. 



A description of this seedling is given by Lubbock $ but there 

 is no figure. 



* Op. cit., i : 422. 



tFlot. Recherches sur la structure comparee de la tige des arbres. Rev. 

 gen. de Bot. 2 : 20. 1890. 

 JOp. cit. I : 322. 



