JOHN B. SMITH, SO. D, 369 



This is the most strikingly marked of all the species and is recog- 

 nizable at a glance. The palpi diifer from those of all save geome- 

 tralis in that the terminal joint is shorter, less cylindrical and prac- 

 tically in line with the second joint instead of being directed for- 

 ward and at an angle with it. 



In the male the underside of the primaries has an oblique patch 

 of somewhat stiff hair extending from tlie cell toward inner nuirgin, 

 the hair directed outwardly and upturned at its tip. Strictly there 

 are two parts to this patch : one along the median vein directed into 

 the cell ; the other crossing the submedian interspace opposite the 

 end of the median vein, the hairs directed outwardly. 



The posterior tibiae of the male are irregularly dilated and exca- 

 vated or grooved above, and toward base at the inner side of an 

 enlargement a dense tuft or pencil of hair is attached. This struc- 

 ture is concealed by covering hair and scales when in position on 

 the insect so that only a somewhat enlarged tibia is apt to be noted. 

 The subapical spurs of this tibia are slender and weak, and there is 

 apparently only one terminal spur. 



At the base of the abdomen is a pair of pencil tufts; the larger 

 and outer white, the smaller, and inner blackish or dark brown. 

 The first abdominal segment is composed of the dorsal sclerite oidy, 

 and terminates abruptly at the sides. Attached to the lateral 

 edges of this segment is a cup-shaped structure which bends around 

 to the ventral surface. The opening of this cup is closed by an 

 operculum of elastic tissue, which, apparently, can be extended and 

 withdrawn at will. At the end of this operculum is a knol) shaped 

 structure to which the long hairs that form the outer pencil are 

 attached. This pencil, fully extended, reaches to the end of the 

 third abdominal segment. The groove into which this pencil fits 

 and in which it is normally concealed does not extend much beyond 

 the base of the third segment, so that the tip of the pencil is curved 

 up at the tip when in place. At the base of this outer pencil and 

 inside of its point of attachment is a smaller pencil of finer, dark 

 hair which does not seem to be stalked. It is not recognizable as 

 distinct from the outer tuft until the specimen is examined in liquid 

 or in a very fresh example. 



Finally, there is at the end of the abdomen a short retractile 

 brush with round truncate tip, which may be withdrawn into a 

 cavity opening at the end of the 7th abdominal segment beneath. 



TRANS. AM. ENT. SOC. XXXIII. (47) DECEMBEB, 1907. 



