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committee, to inspect the wood-working classes at our manual 

 training school at St. Albans. The instructor called my attention 

 to a trunk of silver fir, which had been bought from a local dealer, 

 and which <vas so extensively tunnelled by wood-feeding larvie as to 

 be useless for school purposes. I got him to put the wood on one 

 side for observation, and a few days after I was asked to examine 

 an insect which had emerged from it, and which proved to be a 

 female Sire.v noctilio. This was followed by the emergence of 

 numerous other specimens, which continued to make their appear- 

 ance until the cold weather set in. I was much interested in this 

 saw-tiy infestation, and obtained a number of specimens of the 

 damage done to the timber, some of which are shown in this case. 

 The specimens I exhibit illustrate in a remarkable waj^ the life- 

 historj- of the creature. The tunnels can be traced horn, the point 

 at which the egg was probably deposited, to the pupa cell. As the- 

 larva grows, its burrow, of course, becomes larger, and as it pro- 

 gresses it fills up the space behind it with the rejected woody frass,. 

 which is so tightly squeezed together as to necessitate the use of a 

 knife or bradawl to clear the tunnel of the refuse. The holes made 

 by the escaping flies are clearly shown in some of the pieces of 

 wood. A good deal of the tree had been sawn into planks, and 

 these were piled one above the other against the wall of the baildmg, 

 so that after leaving their pupa cases the flies had to bore through 

 a succession of planks to obtain their liberty, and this they did 

 apparently without inconvenience. 



" Strangely enough during the time I had Sirex noctilio under 

 observation, my co-secretary at the County Museum, the late Mr. F. 

 G. Kitton, a clever artist in black and white, and a Avell-known 

 Dickens enthusiast, brought me a specimen of another species of 

 Siir.r, the giant saw-fly, S. <ii<ias, which so far as ray experience 

 goes, is a commoner insect. It appeared in his wood-cellar, and 

 greatly frightened the servant, who took it to be a hornet, as most 

 people do. From that time onwards a good many others appeared. 

 Investigation showed that they were emerging from a heap of fir- 

 wood, and Mr. Kitton brought me the piece of wood now in this 

 case, which shows the ends of the tunnels from which they escaped. 



"I made enquiries as to the origin of the timber in both instances. 

 In the case at the manual training school, the tree, a silver fir, had 

 been grown upon the estate of Mr. Lewis Evans, F.S.A., at Russells^ 

 near Watford ; while the wood in Mr. Kitton's cellar was the remains 

 of a fir tree of an undetermined species, which grew in his garden 

 at Pre Mill House, near St. Albans. The last-named tree had been 



