THE LEPIDOPTEROUS GENUS PAMPIIILA. 345 



3. Fore wings with semi-hyaline spots in the median interspaces sylvanoides. 



3. Wings without trace of hyaline spots 4. 



4. Ground color of under surface of hind wings grayish green 5. 



4. Ground color of under surface of hind wings, olive or yellow green 6. 



5. A large species; markings on under surface of fore (vings, below the middle median nervure, generally 

 very ill-defined; hind wings slightly but distinctly produced next the inner portion of the outer mar- 

 gin; band of under surface of hind wings broad and usually connected ; inner area of same surface 

 tinged distinctly with buflF; distinct blackish patches at tlie base of the median interspaces on the 



upper surface of the fore wings Juba. 



5. A rather small species ; markings on under surface of fore wings, below the middle median nervure, gen- 

 erally well-defined, at least above ; hind wings with a scarcely perceptible fullness to the outer margin 

 next the inner border ; band of under surface of same wings moderately broad, often broken ; inner 

 area of same surface slightly paler than the i-est, but scarcely tinged with buft"; faint dusky patches at 

 the base of the median interspaces on the upper surface of fore wings; or, usually, these parts are no 



darker than the surrounding field Nevada. 



6. Mesial band of the under surface of the hind wings bent at an angle of about 45° or 50° ; sjiots of 



this band generally vivid, approaching the outer margin of the wing so closely in the interspace 



beyond the cell as to be removed from it by less than their own width .... Colorado. 



6. Mesial band of the under surface of the hind wings bent at a right angle, or a little less than a liglit 



angle, the spots generally not very vivid, separated from the outer margin in the interspace beyond 



the cell by at least tlieir own width, and ordinarily by much more than that 7. 



7 Spots in the interspace beyond the cell generally smaller than the others which make up the mesial Ijand 

 of the under surface of the hind wings, giving the baud an irreguhu- appearance ; spots of the lower 

 portion of the band generally confluent ; the Y-shaped spot, traversing tlie cell near its extremity, very 

 seldom crossing the median nervure to the medio-submedian interspace and not enlarged there ; basal 

 half of fringe on the hind wings, as seen beneath, generally not at all or very inconspicuoush- inter- 

 rupted with dusky at the nervure tips Manitoba. 



7. Spots of the mesial band on the under surface of the hind wings pretty uniform in size, those of the inter- 

 spaces beyond the cell seldom any smaller than the others, so that the band has a more regular appear- 

 ance than in P. Manitoba; spots of the lower portion of the band distinctly marked, sometimes even 

 independent; the V-shaped spot traversing the cell near its extremity, always crossing the median 

 nervure to the medio-submedian interspace and enlarged there; basal half of fringe on the hind wings, 

 as seen beneath, generally conspicuously interrupted with blackish at the nervure X\])S . . comma. 



TABLE TO DETERMINE THE MALES OP THE SPECIES OF PAMPHILA; DRAWN FR03I THE ABDOMINAL 



APPENDAGES. 



1. Hook and lateral arras of upper organ separated by a deep cleft, about half the length of the horizontal 

 portion of the oi'gan ; hook slender, as viewed from above ; clasps not extending nearly so far back as 



the upper organ 2. 



1. Hook and lateral arms of upper organ separated by a slight cleft not quarter the length of the hori- 

 zontal portion of the organ ; hook very stout as viewed from above ; clasps extending almost or quite 



as far back as the upper organ 3. 



2. Hook and lateral arms nearly parallel, and but slightly separated ... .... Nevada. 



2. Hook and lateral arms op])Osed to each other by ojiposite cin-ves, leaving a fusifomi space between 



them, as viewed laterally Scissacus. 



3. Clasps, when viewed exteriorly, with two conspicuous superior apical teeth 4. 



3. Clasps with but one conspicuous apical tooth sylvanoides. 



4. Apical teeth of cl.asp equally separated from each other from base to summit ; clasp itself much 



broader at base than elsewhere, about twice as long as broad 5. 



4. Apical teeth of clasp diverging slightly fi-om each other ; clasp itself elongated, tapering but little, 

 much more than twice as long as broad Ottoe. 



MEMOIKS BOST. SOC. XAT. HIST. VOL. H. 87 



