STORKS AGRICULTURAL EXPERIMENT STATION. 



323 



irrespective of their size. Leaf -scars may be level with the twig or 

 rnor'e or less raised with their surfaces parallel with the twig or 

 making various angles with it up to a right angle. Ridges in 

 some cases run down the twig from the base and corners of the 

 leaf-scar. 



At the bases of the leaves of some species a pair of small leaflets 

 called stipules are regularly formed and leave, at the fall of the 

 leaf, more or less definite stipule-scars at either side of the leaf- 

 scar as shown in the Carolina Poplar (fig. 5). 



The number, the size, the relation to the surface of 

 the leaf -scar whether sunken or projecting, and the 

 distribution of the bundle-scars form important points 

 of distinction. When they are indistinct, as is fre- 

 quently the case, they may be revealed if a thin slice 

 is taken off the surface of the leaf-scar. This surface 

 section must be very thin, however, since the number 

 of bundle-scars exposed by a deep cut is often different 

 from that on the surface, and this latter number is the 

 one used in the keys and descriptions. A distinction 

 -SX is made between a group in which the bundle-scars 

 form a single line and a second group in which they 

 are variously scattered and grouped or in a 

 double line. 



BUDS In regard to their position buds are ter- 

 minal or lateral. Buds produced at or near the nodes 

 but not in the axil of a leaf-scar are called 

 accessory buds. Of these there are two kinds: Super- 

 posed buds located above the axillary buds and 

 collateral buds located at either side of the axillary 

 buds. The former are shown in the Butternut (fig. 6) 

 and the latter in the Eed Maple (fig. 7). Classified 

 p according to what they produce there are flower buds 

 Fie. 5. Twig of which contain the rudiments of flowers, leaf buds 

 Carolina Pop- ^^ con tain rudiments of leaves, and mixed buds 



stlpu s e car . which produce both flowers and leaves. Flower buds 

 P "p1th r " shaped are generally stouter than leaf buds. 



