GALLS 



most beautiful of the lenticular galls, and one of the most abundant, nearly 

 700 having been counted on a single leaf, covering practically the whole of 

 the under-surface. It appears as a small flat disc, about -J- in. in diameter, 

 the prevailing colours being golden yellow, bright ochre, and golden brown. 

 It is common from August to October, and the imago emerges during 

 March or April, earlier than those of any other leaf gall. The alternate 

 sexual generation is seen in 



The Blister Gall (Spathegaster vesicatriv). This, as its name implies, takes 

 the form of a small blister in the blade of the leaf. It may be found from 

 May to October, but is not easy to detect. 



The Oak Apple {Term terminals) is, on the other hand, familiar to every 

 country school-boy, and is largely in evidence on the 29th of May, the day 

 of all others most closely associated witli "King Charles's Apple." It is 

 usually developed from a terminal bud, but those from axillary buds are 

 also of very frequent occurrence. It is yellowish-white, suffused with pink 

 and red, and measures 1-2 ins. in diameter. Growth is complete by the 

 end of June, but the "apple" may be found throughout the year. The 

 imagines emerge during June and July. The alternate asexual generation is 

 found in 



The Root Gall (Biorhiza aptera). This usually takes the form of a con- 

 glomerated cluster on the roots and rootlets, and may measure H in. in 

 diameter. It may be pink, red, or of varying shades of brown. Growth is 

 complete by the end of October, and the imago emerges during the winter 

 or spring. The females are mostly wingless. After leaving the gall the 

 female creeps up the bole of the tree, along a limb, and selecting a terminal 

 bud, bores holes with her ovipositor, the ova being pushed down the holes 

 till they form a mass at the base of the bud. The resulting gall is the Oak 

 Apple. 



The Marble Gall, or Oak Marble, is the work of Cynips Kollari. It is 

 one of the most familiar galls, and is often erroneously spoken of as the 

 oak-apple. It is usually noticed when the hedgerows are leafless, and then 



has much the appearance of marble, being spherical, and brown in colour. 



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