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numerous. This species (II. pinipcrda) is, however, much too large a subject 

 for the present occasion. Hylurgus pilosus, the ivy species, is rare as a British 

 insect. Odd specimens often occur ; but as no one has observed its habits, it has 

 never been found in any quantity. I have found it in almost any ivy that 

 was in iiroper contlition for its attack. Neither healthy living ivy, nor faggots 

 cut from the tree, suit its taste, but ivy, when sickly and dying, is at once 

 attacked. There is a fashion observed in many districts, of simply cutting 

 ivy across or removing an inch or two from its stem, the result of which, as 

 is well known, is not the immediate death of the plant ; it usually siirvives for 

 a year or two. The back of either the upper or lower (but usually the upper) 

 section of ivy so treated is a favoiu-ite habitat of Hyhirgus pilosus. In this the 

 parent beetle makes a burrow of about an inch in length, often half round the 

 stem, and the eggs are laid rather irregularly along its sides and covered over 

 with frass. The larvje eat galleries at right angles to this, sometimes as regular 

 and symmetrical as those of Hylesimes fraxini. When examining ivy for this 

 beetle last spring, I found one of its habits very disappointing. It eats shallow 

 grooves on almost any ivy, though usually on such smaller stems as do not suit 

 it for oviposition, and along the side in contact with the supporting tree ; and 

 I often found abundant traces of this sort without any beetles — they were 

 obviously merely eaten as food by the beetles, who had temporarily sheltered 

 themselves behind the ivy, and abandoned it for more promising material at the 

 first opportunity. All the Xylophaga eat largely while in the perfect state, 

 and unless they find a nidus for oviposition at once, they commence to browse on 

 any food at hand. 



I have found that during the present warm summer many species have 

 emerged at the end of July, which do not usually become perfect until September, 

 and then do not emerge before spring. Every season, probably, a small propor- 

 tion is perfected early ; just as this season, a few, following their usual habit, 

 remain until spring. Wliat do these prematurely-developed specimens do ? 

 Crt/phalus binodulus I find (August, 18G8,) busily engaged in oviposition just 

 as they were in May. Hylurgus pilosus, Hylesinus crenatus, and H. fraxini, 

 I find eating galleries, in each of which there is only one beetle, and as the bark 

 is not such as they usually choose for oviposition, and there is no sign of that 

 process being carried on, I conclude that they intend te hyhernate in these 

 burrows and to postpone oviposition until spring. Though Hylurgus piniperda 

 and Scolytus destructor have almost all emerged, I have had no opportunity of 

 tracing them further. 



In the genus Hylesinus and in Cryphalus binodulus, I always find a pair of 

 beetles in each burrow during the entire period of its construction. Hylurgus 

 pilosus is often found in pairs, but the male usually leaves before oviposition is 

 complete, though with tliis, as with the former species, pairing occurs in the 

 burrows, and probably only there. The economy of Eylastcs palliatus is similar. 

 In the burrows of Hylurgus piniperda, I have rarely found both beetles, and 



