Woodworkers 



the insect responsible for the oak apple can never produce 

 a spangle gall, any more than the insect which produces 

 the robin's pincushion on the rose can make the pea gall 

 on the same plant. 



The Bedeguar, or robin's pincushion of the rose, is one of 

 our commonest galls ; the bright red woolly growths are 

 familiar objects of our country lanes. The female gall 

 insect lays its eggs in the stem of the rose, so that they 

 come in contact with the cambium. Now the cambium 

 is the part of the plant which forms the new tissue and 

 is very susceptible to any irritant. So long as the gall 

 insect remains in the egg stage no gall is formed ; but 

 with the hatching of the egg, the malformation, for a gall 

 is nothing more or less, begins to grow. And the cause 

 possibly the constant gnawing of the little grub, probably 

 some irritant substance which it gives off from its body, 

 or, very likely, both combined. This particular gall differs 

 from most others in that it contains several larvae instead 

 of a single one, as is usually the case. As these larvae 

 develop, the well-known red pincushions come into being. 

 Their woolly outgrowths are really malformed leaves, the 

 best that the plant can do under the circumstances. 



We will devote our time to a study of the oak which will 

 supply us with one of the romances of insect life. The 

 objects of our investigation for the moment are the common 

 spangle and currant galls. The former are to be found on 

 the under side of the oak leaves about July ; the latter 

 hang from the catkins or leaves early in the year. We 

 have said that the same species of gall insect always 

 produces the same kind of gall ; the insect producing 

 spangle galls is of the same kind as the one producing 

 currant galls : are we then guilty of a " terminological 

 inexactitude"? By no means, for these particular gall 

 insects provide examples of a very wonderful phenomenon 

 known as alternation of generations. 



We have studiously tried to avoid wearying or perplexing 

 our readers with technicalities or obstuse theories, but 



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