THE CANADIAN ENTOMOLOGIST. 



of the wood. The coarser splinters are not detached entirely from the 

 wood, but are split up by the larva all around the top of the cell, and 

 project like bristles, appearing somewhat as those wooden toy-trees which 

 are made for children, and which are formed by shaving down the wood 

 and leaving the shavings still adhering by one end. These splinters make 

 a firm wad. Against them are piled a quantity of finer chips or thin 

 filings, which are loose, but pressed together. 



The cell is about 40 mil. from the outer bark of the tree, and 

 the chrysalis makes its way to the air through the burrow by means 

 of its teeth on the segments and the spinose process on the front, by 

 which it forces itself, by stretching and contracting the abdomen, through 

 the wood scrapings which close the cell, until it comes to the end. We 

 have noticed a fine thread of silk proceeding from the spinneret of the 

 larva, although in the puparium we have found no silk whatever. The 

 puparium seems to have been formed by wedging first coarser, and then 

 finer strips of the wood together, and seems to be merely a more carefully 

 and smoothly finished enlargement of the original burrow. 



A specimen of the pupa which I have examined is about 30 mil. 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 caputal appendages are visible, and here and there arise 

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

 vided 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. 



The moth seems to belong to the genus Cossus Fabr., and not to be 

 congeneric with Xystus robinicz. The head is short, eyes naked, labial 

 palpi small, appressed, scaled. The thorax is thickly scaled, the scales 

 gathered into a ridge behind, and is squarer in front than in Xystus, not 

 so elongate, or so elevated dorsally. The male antennas are bipectinate, 

 the lamellae short, rather broad and ciliate. The female antennas are 

 serrated. It is allied to the European Cossus terrebra, while a larger 

 insect. It differs from C. <juerciperda by the absence of any yellow on the 

 male hind wings, and by its darker color and closer reticulations. 



In color this species is black and gray ; the edges of the thorax and 

 collar are shaded with gray — more noticeable on some specimens than 

 others. The primaries are covered with black reticulations, which are not 



