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struction I do not know ; in some kept under observation, about a dozen eggs had 

 been laid in three weeks from the date of commencement of a burrow. The eggs 

 are situated rather closely together, each in a little hollow scooped out of the bark ; 

 and they, as well as the insterspaces between them, are covered over with a layer 

 of fine frass, which does not appear to have been eaten ; so that the sides of a 

 completed burrow are formed of this frass, behind which are the eggs. The larvaa 

 start in every direction from the parent gallery, but tend to travel vertically ; so 

 that, when full grown, most of them do so. The greater part of the broods become 

 perfect beetles in late autumn, and pass the winter at the ends of the larval 

 burrows, slowly eating a gallery upwards or downwards, according to the direction 

 the larval gallery had assumed. I have seen galleries so eaten for winter sustenance 

 more than an inch long ; the majority, however, eat very little. 



What becomes of those beetles that escape in autumn I do not know ; their 

 number is not great. Others, also few in number, remain as larva? throughout the 

 winter ; and I have found odd beetles, and even larvae, under bark from which the 

 broods had apparently gone during the previous year. 



Hylastes obscurus also attacks furze, but is more particular as to its pabulum 

 than P. rhododactylus ; it rarely attacks stems of less than an inch in diameter, 

 and rarely, almost never, cut-down sticks ; it is partial, however, to the stumps 

 that remain in the ground, and stems of jjlants dying of age. The latter frequently 

 die on one side first, and this first-dying side is the favourite habitat of H. obscurus. 

 The sticks that it has abandoned for one or more years are very numerous, as 

 compared with those that still contain it ; whereas, with P. rhododactylus, abandoned 

 sticks are rare. This probably arises from rhododactylus more completely separating 

 the bark (leaving a very beautiful " typograph "), and from the smaller size of the 

 branches affected by it causing them much sooner to assume the aspect of dead and 

 rotten wood ; whereas those long abandoned by obscurus often continue to look as 

 if they might contain the beetle, until they are quite rotten. I have found few 

 likely stems of furze without traces of obscurus, but only a small proportion with 

 hat beetle still present. I have also found it, though not abundautly, in broom. 



The parent gallery of obscurus has only one branch, which is very straight, 

 accurately transverse to the stem, and | of an inch to an inch in length. I usually 

 find only one beetle in it, but I have several times found a second, which I believe to 

 have been the male, and in these cases there was usually an abortive branch of the 

 burrow in the opposite direction from the main one, about the length of the beetle j 

 apparently eaten by the male for food, and containing no eggs. 



The eggs are laid at the bottom of little cavities on either side of the burrow, 

 and covered by frass, which fills the cavities to the level of the wall of the burrow, 

 of which there is usually a small unoccupied portion between each cavity, often of 

 such a length that it looks as if four or five eggs had been omitted. I have sup- 

 posed that the male, or several different males, came and went during the con- 

 struction of the burrow ; and that these blanks represented periods when the male 

 was too long absent, as I have found them also in other species where the male is 

 sometimes absent, but very rarely in any species in which the male is always 

 present or always absent. I have found eggs laid so near the advancing extremity 

 of the burrow that the beetle must have come out and gone in again backwards to 

 have laid it, though I have never seen a beetle in this position. The number of eggs 



