116 BUDS AND STIPULES 



stipules are minute in the bud, or even absent, and this 

 function is performed mainly by the leaves. 



The stipules, however, though always very small in 

 bud, and in some species (S. retusa, Grahami, Caprea, 

 repenSj &c.) permanently so, in others become larger, 

 and in some (8. dasyclados, myricoides, &c.) attain a 

 considerable size. Their chief function appears to be 

 to protect the axillary buds, which are also sheltered by 

 the dilated and concave bases of the petioles. That the 

 winter-buds of the Willow should be protected by modi- 

 fied leaves is the more remarkable since some species at 

 least subsequently develop large stipules. 



Ohlert (17) mentions the Willow among the cases in 

 which there is no terminal bud. At any rate, it appears 

 rarely, if ever, to maintain itself permanently. But, 

 although as a rule it soon perishes, it is formed on the 

 same plan as the lateral buds. 



VIBURNUM (THE GUELDER ROSE) 



The winter-buds of the Guelder Rose (Viburnum 

 Opulus), both terminal and lateral (PL II. fig. 1), are 

 oblong-oval, varying considerably in size, according to 

 their situation on the shoots and the strength of the 

 latter. Each bud is covered by two pairs of scales, 

 which are modified petioles bearing just a trace of an 

 undeveloped lamina at the apex. 



The outer pair of scales are the most modified and 

 cohere by their edges ; they are inserted right and left 



