104 Dr. H. Eltringham on Specific and 



possible to separate the following reputed species and their 

 forms from the remainder of the Silvaniformes. 



H. ismenius. 



,, " silvana " metaphorus. 

 ,, narcaea. 

 ,, numatus. 

 ,, ethilla. 

 ,, gradatus. 



The first two above are separable from the rest on general 

 differences in the armature, and we may now consider the 

 remainder. 



H. narcaea, Godt. 



The typical form of this well-known species occurs in 

 S. Brazil. In Seitz' ab. connexa the subapical band is 

 completely separated and surrounded by black. The 

 form satis, Weym., has a brown instead of a yellow band 

 in the hind- wing. The form flavomaculatus, Weym., has 

 a yellow instead of a white apical spot in the fore-wing, 

 whilst physcoa, Seitz, has the fore-wing yellow band much 

 broader than usual. The form polychrous, with largely 

 increased black areas, is regarded by Stichel and Riffarth 

 as a subspecies, though apparently occurring in the same 

 localities as satis. It cannot be doubted that these are 

 all forms of the same species, as they are for the most part 

 mere colour variations. The outline of the claspers in 

 three of the forms is shown on PI. XIII. In general 

 structure there is considerable agreement, though there is 

 a marked difference between the actual outlines of the 

 typical form and narcaea polychrous. 



H. numatus, Cram. 



Of this species some ten forms have beei\ named, and 

 they extend from Guiana across North Brazil to the Western 

 Amazon region and Peru. The claspers of three forms are 

 illustrated on PI. XIII. The form guiensis is merely a 

 variety of the type, but there is a greater difference between 

 its clasper and that of numatus numatus than between the 

 latter and narcaea narcaea. Indeed, the two last are not 

 appreciably distinguishable. It may be said that they do 

 not occur in the same locality and that thus there is no 

 necessity for the respective armatures to be different. 



