84 C. H. PECK ON THE 



quoted, agrees with Dr. Fitcli in concluding that the excrescences 

 are not of insect origin. He also claims to have carefully watched 

 the black knot through all its stages from its earliest commence- 

 ment to its complete maturity. He affirms that he bred from the 

 galls five distinct species of insects beside the curculio, but that not 

 one of these could be considered a true gall maker. He, there- 

 lore, very justly concludes that the excrescences are not of insect 

 origin, but of fungoid origin ; and this conclusion, we may add, is 

 entirely in accordance with our own view of this subject. Our 

 reasons for adopting this view are briefly these : — 



1st. The excrescence itself is similar in structure to other ex- 

 crescences which are known to be of fungoid origin, and at the 

 same time it is quite dissimilar to most insect galls produced in 

 twigs and young branches. 



2nd. The time of its development is opposed to the probability 

 of its insect origin. We are well aware that our knowledge of in- 

 sect galls is extremely limited, and that here we are treading on 

 dangerous ground and may hereafter be obliged in our turn to 

 apologise to the entomologists, but so far as our observations ex- 

 tend, insect galls are developed in the warmer seasons of the year, 

 i. <?., in spring, summer, and possibly early autumn. Those that 

 continue to be the domicile of the young insect during the winter 

 are, so far as we have observed, fully grown in autumn, and do not 

 increase in size the following spring, a character which does not 

 hold good in the case of black knot. 



3rd. The furgus is always present with the excrescence, and its 

 mycelium may be detected even in the earliest manifestation of the 

 tumour, and this fungus is never found apart from the black knot. 

 To our minds this alone is a sufficient argument for our belief in 

 the fungoid origin of the excrescence. Who ever heard of any 

 undoubted insect gall being always accompanied and inhabited by 

 a fungus? On the other hand, the larvae of insects are not always 

 present in the excrescence, and of those insects that have been bred 

 from it, none, we are told, have been true gall makers. 



Like others from whose writings we have quoted, we also claim 

 to have examined the black knot carefully in its various stages of 

 development, not entomologically it is true, but botanically, from 

 which it is not unreasonable to suppose that we may have observed 

 some details in its development which escaped their notice. We 

 desire, therefore, to express the results of our own observations, 



