4.76 NEW YORK STATE MUSEUM 



Poplar carpenter worm 



Cossus coiicrcHsis Lint. 



Stout, white, naked caterpillars about i "2 inches long, bore in poplar trunks. 



This comparatively rare species was first described by Dr Lintner from 

 specimens taken on poplars at Karner, then Centre. It appears to be 

 rather rare, though occasionally it may become quite abundant, as evidenced 

 by our finding many larvae of this species in a badly affected cottonwood 

 tree in Albany. This insect has been taken in the vicinity of New York 

 city, and Dr Smith is of the opinion that it occurs in New Jersey. It has 

 been recorded from the Atlantic States by Dr Dyar, and Dr Fletcher has 

 found it about Ottawa Can. 



Description. Larva. Head dark brown; mouth parts nearly black; 

 thoracic shield pale yellowish, with a sublateral, oblique darker line on each 

 side , body creamy white. Length about i 34 inches. 



Labium yellowish white, broad at base, sutures brown ; spinneret con- 

 spicuous, brown, slender; labial palpi very small, i segmented and bear- 

 ing two minute apical setae ; ma.xillary palpi 3 segmented. Mandibles 

 dark brown, apex black, with two inconspicuous teeth ; epistoma yellowish 

 brown, tuberculate and bearing a number of stout, short setae ; labrum yel- 

 lowish, smooth. Clypeus dark brown, sutures black. Antennae very short, 

 basal segment yellowish white, apical brownish and bearing a conspicuous 

 seta. Simple eyes few, yellowish brown, with a few setaceous tubercles 

 interspersed. Thoracic shield weakly chitinized, yellowish, with a distinct 

 sublateral, oblique line on either side. Anal shield yellowish, weakly chiti- 

 nized ; body tubercles rudimentary and represented only by sparse hairs, 

 spiracles dark brown'. Thoracic legs well developed, claws black, the tip of 

 last segment dark brown. Well developed prolegs on the third to the sixth 

 and last abdominal segments. 



The pupa has been described by Dr Bailey as " about 30 mm in 

 length, narrow, brownish black, shining, rugose. The clypeus presents a 

 strong, broad, spinous process, supported at base by lateral projections. 

 On the underside it descends into a wide sulcation terminating in a broad 

 projection. The capital appendages are visible, and here and there arise 

 isolated hairs as in the previous stage. The abdominal segments are 

 provided with teeth over the dorsum, decreasing in size to the stigmatal 

 line. The anal segment is provided with two unequal-sized terminal teeth 

 on each side of the vent."* 



This adult has been described by Dr Lintner as follows: 



