74 MINNESOTA BOTANICAL STUDIES. 



month after sowing. The seed coat is sometimes carried above 

 ground, but it as often remains in the soil. 



The hypocotyl is stout, 25-30 mm. in length. The cotyle- 

 dons are sessile, slightly auriculate, oblong, 18 mm. in length 

 and 9 mm. broad. They do not increase greatly in size. 



Leaves are alternate and pinnate. The second appears be- 

 fore the first is fully open. The first leaf usually has eight pairs 

 of leaflets, the second has eleven pairs, the third thirteen pairs. 

 When these leaves have developed the hypocotyl is about 50 

 mm. long, the epicotyl 20-25 mm. 



The first leaves are described by Tubeuf * as having ten pairs 

 of leaflets. In the plants examined by the present writer the 

 first leaf had never more than nine pairs of leaflets. • 



PAPILIONACE^. 

 Amorpha fruticosa Linn. 



This is an ornamental shrub indigenous to North America 

 and frequently cultivated. The seeds germinate in about two 

 weeks after planting. 



When the cotyledons first appear they are ovate in shape, 

 about 5 mm. long and 2.5 mm. broad. By the time they are 

 fully open they measure 8 mm. in length. The hypocotyl at 

 this time is 25 mm. long, quite slender, gradually thickened 

 below. 



The cotyledons attain a length of 12 mm. They are sessile. 

 The epicotyl is 15 mm. in length. Foliage leaves are alternate. 

 The first five or six are simple, broadly ovate, petiolate. After 

 these the leaves are, for a space, pinnately trifoliate. The 

 terminal leaflet is larger and longer stalked than the lateral ones. 

 Later leaves are pinnate with numerous leaflets. 



Amorpha nana Nutt. 



The seedlings of this shrub resemble those of A. fruticosa save 

 that they are much smaller. The hypocotyl does not become 

 more than 8 or 10 mm. in length and the epicotyl is only about 

 5 mm. long. Cotyledons are 5 mm. long and 3 mm. broad. 



Leaves are alternate. The first six to ten are simple. They 

 are broadly orbicular, emarginate, petiolate, with a distinct mid- 

 vein. As in the former species the later leaves are pinnately 

 compound. 



* Samen, Friichte und Keimlinge, 12". 189I. 



