684 NEW YORK STATE MUSEUM 



Spruce cone worm 



Diorxclria rciiinilclla Grote 



A red-headed, brownisli caterpillar about -"^a inch long, feeds on young fresh spruce 

 cones, surrounding them with a mass of webbed excreta. 



This species was brou^'ht to our attention b_\' the receipt of a large 

 number of infested cones colh'cted in the Adirondacks. The attack, 

 according to Dr Packard, is usually confined to the young cones, into which 

 the larvae bore and mine in different directions, excavating galleries in the 

 interior and separating the scales from the axis of the cone. The cater- 

 pillar may mine one cone and then pass into an adjoining one, spinning a 

 rude silken passage between the two. Occasionally a Ijunch of three or 

 four cones is tied together with silken threads, in which latter masses of 

 castings or excrement become entangled. 



Description. The larva has been described by Dr Packard as follows : 



Head and prothoracic shield deep amber brown ; the body reddish 

 carneous or amber brown, with a livid hue; a faint, dark dorsal, and a 

 broader, subdorsal line ; piliferous warts distinct ; each segment divided 

 into a longer anterior and shorter, narrower, posterior section, bearing two 

 dorsal piliferous warts, besides a lateral one. 



Length 5/,6 inch. 



The parent insect has its fore wings ornamented with light and dark 

 gray. There is a broad basal light patch and before the middle of the wing 

 a white zigzag line and near the outer margin another white zigzag line 

 with a dark border. Wing expanse about .^4 inch. 



This is considered by Ragonot to be a synonym of the closely allied 

 I), d e c u r i e 1 1 a Hiibn., a form which feeds both on firs and pines, and it 

 is possible that the species untler description has similar food habits. 

 There is no practical method of preventing its depredations, were it desir- 

 able, other than collectino- and burnin<r the infested cones before their 



inhabitants have escaped. 



Bibliography 



1890 Packard, A. S. U. S. Ent. Com. 5th Rep't, p. 854-56 



