BULLETIN 



OF THE 



BROOKLYN ENTOMOLOGICAL SOCIETY 



Vol. VIII February, 1913 No. 3 



A New North American Butterfly in the Family Lycaenidae. 



By William Phillips Comstock. 



Strymon titus, Fabr. 



Var. immaculosus, no v. 



cf and 9 . This variety is slightly smaller in size than the 

 normal form of 5. titus Fabr. (expanse of cf from 28-30 mm., ? 

 from 30-34 mm. as compared with cf 30-35 mm., ? 33-38 mm. 

 in normal specimens*). 



The head, thorax, abdomen and appendages do not differ 

 from the normal form. 



The upper surface may be as in the normal form of & and ? , 

 a satiny seal brown with slight greenish reflections (Figs. C and 

 D), or in a series of specimens, the surface may become gradually 

 suffused with fulvous, until an extreme form is reached in which 

 the outer half of the disk of the primaries in both cf and ? is 

 completely covered with fuh'ous scales and there appears a com- 

 plete row of marginal red-orange or fulvous spots on both primaries 

 and secondaries in d' and * , although on the primaries these 

 spots become lost in the ground color in extreme specimens such 

 as are shown on the plate. Figs. A and B. 



Cn the underside the ground color varies, some specimens 

 being like the normal form, and others of a paler shade. All black 

 markings are obsolete to absent (Figs. E, F, G and H), showing as 

 mere pin points even where best defined. In these specimens a 

 trace of the white markings occurs as a few scattered scales about 

 the black markings. The red m.arginal spots of the secondaries 

 are retained for the most part in reduced size, but in those speci- 

 m.ens wJiere the row of red spots is repeated the full marginal 

 length of the primaries, the secondary row is of fully normal size 

 and appears more prominently because of the obsolescence of 

 other markings on all four wings. 



*Measurement ir.ade from tip of wing to center of thora.x and doubled. 



