. Circular. Insect pests; Insect pests. strips, and punching holes for tacks in the tips of the strips (fig. 2). This was found to be achnirablj^ adapted to the work; it was durable, could be readily fitted to an^^ surface, and was easil}^ examined by simply removing the lid. The investigations were started too late in the season to secure the pupfe or adults, but many larvae in various stages of development were collected and studied, and a num- ber of the infested wounds were covered with the tin cages. The most important result of the first season's work was the discovery that the primaiy c
. Circular. Insect pests; Insect pests. strips, and punching holes for tacks in the tips of the strips (fig. 2). This was found to be achnirablj^ adapted to the work; it was durable, could be readily fitted to an^^ surface, and was easil}^ examined by simply removing the lid. The investigations were started too late in the season to secure the pupfe or adults, but many larvae in various stages of development were collected and studied, and a num- ber of the infested wounds were covered with the tin cages. The most important result of the first season's work was the discovery that the primaiy cause of the attack and subsequent injury b}' the bark maggot was the work of the hem- lock barkbeetle {Hylesimis n. sp.) /'- (lig. 3, a)^ which was found exca- vating short burrows (fig. -), h,c) in the health}' bark, and through it to the surface of the wood, where a small wound was made, causing -^â - a slight flow of resin (fig. 8, /). These burrows were evidently made by the beetles for the purpose of obtaining food, and not for the i^' purpose of depositing eggs, since neither eggs nor larvae of the beetle were found, and the burrows were soon abandoned. Some of these of the Llackcheok in west- food burrows were healed over with- ^^" liemlock: «,, the beetle {Hi/leslnus u. sp.) that makes the primary injuryânatural size; b, entrance of beetle in outer bark : c longitudinal section of a similar entrance; </, same as b, showiuR wound in inner bark; e. same, showing wound in outer sapwood; f. resin exuding from an entrance after beetle has koiic ; .r/, fresh resin mass on outer bark. indicatiiiHr hemlock bark magKot at work ; h, longitudinal section of simi- lar mass, showing position of maggot; i, maggot wound in inner bark; .;,same, in outer sapwood: Ic. resin mass after maggot work is done and the pupa is formed; /.longitudinal section of similar mass, showing pupa, the begin- ning to heal (original).. Please note that these images ar
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsectp, bookyear1904
