11 



and covered with scales which sometimes form a pointed tuft at 

 the end. The remaining segments are finely ciliated, those in the 

 males being stronger than in the females. 



The thorax is of medium size, and its covering of scales smooth 

 without any indication of tufts or other characters. The tegulae 

 are of medium length, without long scales, hairs or other unusual 

 characters. The abdomen is long and slim, of nearly uniform size 

 throughout in the male, but somewhat fusiform in the female. 

 The genitalia of the male consist of a pair of long, comparatively 

 thin and broad exserted claspers and a prominent uncus. 



The legs are long and slim with cylindrical segments, except the 

 femora, which are somewhat compressed. The coxae are about as 

 long as the thorax and stouter than the remaining segments of the 

 legs. The fore tibiae have a tibial epiphysis on the inside near the 

 end, the middle tibiae have a pair of unequal spurs at the end, 

 while the hind tibiae have a pair of unequal spurs at the end and a 

 similar pair at the outer third. The tarsi consist of five segments 

 with a pair of claws at the end. There are no spines on any of 

 the segments of the legs, but they are covered by scales that lie 

 smooth and close to the surface. In some species, however, the 

 scales are raised, forming an enlarged ring around the middle and 

 hind legs at the base of the spurs, and a similar ring occurs around 

 the end of the fore tibiae. In one species (monodactylus) there is 

 a small tuft of scales on the hind tibiae, opposite and within the 

 middle spurs (Plate I., figs. 11, 12). This character is very use- 

 ful in determining this exceedingly variable and common species. 



The ground color of the Pterophoridae is generally white, yellow- 

 ish white or some shade of brown, occasionally without darker 

 markings, though the fore wings most frequently have a dark tri- 

 angular spot resting on the costa and extending down to a point 

 just within the end of the fissure. One or two light lines cross the 

 lobes obliquely, and there is a dark spot on the cell a little before 

 the middle of the wing and another on the fold still nearer the base 

 of the wing. The hind wings are of one uniform color, and seldom 

 have spots or lines of other colors. 



HABITS. 



The usual time of flight is on warm, calm evenings, when they 

 are occasionally attracted to light and rarely to sugar. They may, 

 however, be easily u flushed" in the day time from the shrubbery, 

 when they fly a short distance and alight. When at rest they hold 

 their wings nearly horizontal and at right angles with the body, 



