THE BLACKHEAD FIEEWOEM OF CRANBERRY, 45 



Egg. 



Shining grayish white ; entire surface finely and evenly faceted, smooth. 



This species has appeared in our economic literature and lists under 

 the name vaccinimia Packard, and has been held to be an American 

 species distinct from the European n-aevmia Hiibner, although the 

 synonymy has been long suspected. A careful comparison of the 

 genitalia and external characters of the two shows them to be one 

 species. Another American species, Epinotia ilicifoliana Kearfott, 

 also should be referred to the genus Rhopobota as a variety of 

 R. naevoma. In genitalia it is identical but differs somewhat in pat- 

 tern. Dampf, in a very excellent study of their genitalia, has shown 

 the synonymy of the two European forms naevana Hiibner and 

 geminana Stephens. 



The larva of Rhopobota naevana is easily confused with another 

 cranberry feeder, Peronea minuta Robinson, which it superficially re- 

 sembles. The latter, however, can be at once distinguished by the ar- 

 rangement of setse I, II, and III on the ninth abdominal segment and 

 its different anal fork. In R. naevana I and III are closely approxi- 

 mated and on a single chitinization and the anal fork is two-pronged 

 and very small ; whereas in P. minuta I is well separated from III, 

 about equidistant from both II and III, and both I and III are on 

 separate chitinizations and the anal fork is five or six pronged, large, 

 and rather conspicuous. 



EXPLANATION OF PLATES. 



Plate I. 



Rhopobota naevana: 



A. — ^Adult. C. — Pupa, dorsal view. 



B. — Pupa, ventral view. 



Explanation of symbols applied to pupa. 



a = antenna. 1' = metathoracic leg. 



ao = anal opening. Ip = labial palpi, 



at = invaginations for anterior md = mandible. 



arms of tentorium. mp = maxillary palpus, 



ex" = coxa of mesothoracic leg. ms = mesothorax. 



es = epicranial suture. mt = metathorax. 



f^ = femur of prothoracic leg. mx = maxilla, 



ge = glazed eyepiece. p = prothorax. 



go = genital opening. se = sculptured eyepiece, 



lb = labrum. v = vertex. 



1^ = prothoracic leg. 1 to 10 = abdominal segments 1 to 10. 



P = mesothoracic leg. 



Plate II. 



Rhopobota naevana: 



A. — Denuded forewing of female moth, showing venation. 

 B. — Denuded hindwing of female moth, showing venation. 

 C. — Male genitalia of moth ; ventral view of organs spread. 



D. — Setal map of first and second thoracic, and third, eighth, and ninth abdomi- 

 nal segments of larva, showing arrangement of body setse. 



