68 THE COCCIDAE 



The nymphal males of the third stage are said to be easily 

 recognizable through their longer, narrower, flatter bodies. In 

 each successively older nymphal stage of the female there is an 

 increase in the number of cerores and setae, while in the male 

 there is a corresponding decrease in the number so that the body 

 of the male at this time is almost bare. The antennae consist 

 typically of nine segments. The male as it approaches the close 

 of its third nymphal stage becomes less active and seeks a place 

 where it can conceal itself under some projecting piece of bark 01 

 under some leaves. Having found such a place, it excretes a 

 flossy mass of wax threads which adhere together when they come 

 into contact with each other. The nymph forms a covering or 

 cocoon from this wax by the movements of its body. 



When the formation of the cocoon is completed, the nymph 

 becomes quiescent and soon molts and transforms to a legless indi- 

 vidual. The nymph is quiescent throughout this period, the fourth 

 nymphal stage, and differs from the individuals of the previous 

 period in that it has lost its rostralis and is unable to feed. It has 

 also lost its nymphal legs and antennae and has in place of them 

 the developing antennae and legs and wings of the adult. The 

 insect is quiescent throughout the fourth nymphal period which 

 ordinarily lasts about three weeks. This is the so called pupal 

 stage of many writers. 



The adult males are reddish insects with long, slender, ten- 

 segmented antennae. The mesothoracic wings are comparatively 

 large while the metathoracic wings are represented by a pair of 

 halteres each of which bears two hooks which fit in a fold in a 

 mesothoracic wing. The abdomen is without the long slender 

 lateral prolongations of each side of certain of the caudal abdominal 

 segments so characteristic of many of the males of this subfamily. 



The following table for the separation of the genera of the 

 Monophlebinae is very unsatisfactory. It is based for the most 

 part upon generalities, upon the amount and form of the wax 

 excreted by the adult female and the number of antennal segments. 

 These are characters of slight value in differentiating genera 

 because of their great variation even in the same species. Such 

 genera as Lophococcus, Aspidoproctus, Stigmacoccus, and Perissop- 

 neumon } which are based upon definite structural characters of the 

 body, are readily recognized. The size of the insects, the great 

 number of structural characters, the largest found in any group 

 of coccids, and the presence of structures not present in other 



