26 



THE YOUNG NATURALIST. 



known as "maiden oaks," which, al- 

 though to all appearance healthy and 

 vigorous trees, never produce any 

 acorns. If closely examined, the fruit- 

 bearing organs of such trees will be 

 found to be abortive or altogether 

 absent. The flowers of the oak appear 

 simultaneously with the leaves in April 

 and May. The stamens are borne on 

 long, slender, pendulous catkins, two 

 or three springing from the same point 

 and bearing the flowers in rather dis- 

 tant clusters. Being three or more 

 inches in length, and produced in great 

 numbers, they give the young twigs a 

 fringed or tasselled appearance. After 

 the pollen is shed these catkins wither 

 and drop off, but sometimes they are 

 attacked by an insect which lays its 

 eggs in the flowers ; this causes an 

 abnormal growth like a small berry, 

 and instead of dropping off the catkins 

 remain during the summer, very much 

 resembhng a bunch of currants, thus 

 providing a habitation and a store of 

 food for its unbidden guest. The 

 fertile flowers are very minute, appeal- 

 ing at the extremities of the little 

 twigs, surrounded by numerous scaly 

 bracts, which in due time become 

 hardened and consolidated into the 

 cup of the acorn. The flowers are 

 usually two or three together, and al- 

 though there are three styles and three 

 ovules in the ovary, it is very rarely 

 that more than one seed is developed 

 in the acorn — the abortive remains of 



the other two may be detected in the 

 ripe fruit. It is the same in the hazel, 

 — occasionally a nut is to be found 

 with two perfect kernels, which is the 

 normal number of ovules in the flower, 

 but usually only one is matured at the 

 expence of the other. The fertile flowers 

 are often attacked by insects in the 

 same manner as the staminate, the 

 result is those scaly excresences known 

 as " artichoke galls." The round, 

 smooth, juicy, pink and white ''oak 

 apples" or ''marble galls" which 

 sometimes appear in such numbers 

 upon the twigs and branches, and the 

 bead-like spangles which stud the sur- 

 face of the leaves, are all the abodes 

 in the earlier stages of their existence 

 of various species of insects. Over 

 forty species of gallflies alone have 

 been enumerated on the British oak, 

 and no part of the tree seems exempt 

 from their ravages ; but so far as is at 

 present ascertained the sojourns of these 

 winged visitors do not seem absolutely 

 detrimental to the tree. Mr. Mosley has 

 prepared for this number an elaborate 

 list of insects known to feed upon the 

 oak, but even it might be indefinitely 

 extended. Mr. Coleman in his "Wood- 

 lands " estimates the insect denizens of 

 the oak at 1500, and these are reckon- 

 ed to have 500 ichneumons preying on 

 them. Sometimes the oak may be seen 

 entirely denuded of its early foliage by 

 these predatory attacks — the branches 

 standing gaunt and bare as in winter 



