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of the young shoot, which is completely hollowed out. The 

 nodule is situated at the opposite side of the twig to that on 

 which the gallery is carried, and extends from a point somewhat 

 below the commencement of the gallery up to the new wood ; 

 it consists of an outer and an inner chamber, the former of 

 which communicates at its upper end with the hollowed-out 

 portion of the shoot, while the latter appears to be simply a 

 receptacle for the pupa, and is probably not formed until the 

 larva is about to change. The bark and a portion of the 

 wood of the twig on the side next the nodule are also eaten 

 away, but not to such an extent as to make a direct com- 

 munication with the narrow gallery on the opposite side. 



" If we now compare these two sets of observations, it will 

 be found that they fit the one into the other, and we are able 

 to arrive at a probable life-history of the species, which would 

 appear to be as follows : — The egg is deposited on the twigs 

 of the fir, and upon hatching, the young larva eats through 

 the bark, forms the narrow gallery, and feeds upon the soft 

 wood of the tender shoot then growing ; this operation pro- 

 bably occupying its first summer. It now taps the bark on 

 the opposite side to that by which it entered, and causes the 

 sap to flow, which by its own weight spreads along the twig 

 in the direction of the stem, congeals, and forms a resinous 

 lump, the inside of which the larva gnaws away, at the same 

 time devouring the bark, and a portion of the wood next it, 

 as it becomes covered, until it has obtained a sufficient size, 

 and thus makes a habitation in which to pass its first winter. 

 With the approach of spring the sap begins to flow again, 

 and this probably supplies the larva with nourishment, it 

 attaining its most rapid growth at the time when the flush is 

 greatest. It remains as a full fed larva through its second 

 autumn and winter, pupates in April, and the moth emerges 

 at the end of May or early in June, thus occupying a period 

 of two years in completing its metamorphosis." 



NOVEMBER iA,tk, 1889. 



T. R. BiLLUPS, Esq., F.E.S., President, in the Chair. 



Messrs. E. H. R. Hillsworth, T. Hudson, M. Farrant, and 

 J. P. Nevell were elected members. 



Mr. J. Jager exhibited a bred series of Agrotis ripce, Hb., 



