106 THE PLANT WOELD 



reflexed, spreading, or ascending; whether sessile, stalked on the pro- 

 jecting calyx-tube, or somewhat imbedded in the flesh; remaining green 

 or coloring with the fruit. 



The number of the stamens, 5, 5 to 8, 10 or 20; the size of the fila- 

 ments; the color of the anthers (cream, yellow, pink or purple), are of 

 the greatest importance, as w^ll as the number of styles. The relative 

 time of flowering will often be of value in separating closely" related 

 species in the field while in flower. 



The immature fruit presents few distinctive characters. It should 

 be noted of the mature fruit the date when it ripens and when it falls; 

 its size; the shape (oblong, pear-shaped, globular, flattened, etc.); 

 whether either end is concave; if glabrous or pubescent; its color 

 (green, yellow, orange, scarlet, or mottled wifh several colors); wax- 

 like; dull or shining; glaucous; punctate. 



Of the calyx-cavity, whether it is obcouic or cjdindrous, its size and 

 pubescence. 



Of the seed, the number; whether their sides are smooth or hol- 

 lowed; the backs smooth or grooved; whether placed centrally or apic- 

 ally in the fruit. 



The color and firmness of the flesh are good field characters, as 

 well as the disposition, length, and pubescence of the fruiting pedicels. 



The pubescence, color, and texture of the foliage, as well as its 

 shape and size should be noted; the color of the twigs, and the abund- 

 ance of thorns and their size. In a few species the thorns are 2-ranked; 

 in most, however, they are found on all sides of the twig. 



Many of these characters must be noted in the field, as they are 

 lost in the most carefully prepared herbarium specimens. When once 

 the floral and fruit characters of the thorns are carefully observed, the 

 separation of the forms becomes a simpler task than distinguishing the 

 willows, or even the oaks and hickories. 



Besides the characters given above, the size, habitat, bark, and 

 habit (ascending, spreading), or drooping branches, upturned twigs, 

 drooping or erect leaves, and the coloring of the foliage in autumn, will 

 be of great help to the careful observer. 



Raleigh, N. C. 



