Mr. G. A. K. Marshall on the Genus Byblia. 333 



3. The typical arenaceous Wehbi'nce, as far as I am ac- 

 quainted with thenij have simple non-septate chambers. 



4. Vitriivebbina agrees isomorphically with Nubecularia in 

 that both may exhibit septate commencements. 



5. Vitriwebbina appears to be closely related to Ramulina 

 (the adherent species of the genus) in having similarly 

 septate Polymorphine commencements. 



L. — JSotes on the Genus Byblia ( = Hypanis). 

 By Guy A. K. Marshall, F.Z.S., F.E.S. 



The following is the generic synonymy of Byblia'. — 



Byblia, Hiibner, Verz. bek. Schmett. p. 28 (1816). 

 Byblis, Godart, Enc. M6th. ix. p. 327 (1819). 

 Hypanis, Boisduval, Faun. Madag. p. 55 (1833). 



Personally I am quite at a loss to understand the objection 

 raised by some entomologists to the recognition of certain of 

 Hiibner's genera on tlie ground that he failed to define them 

 properly, seeing that at the same time they are quite prepared 

 to accept such Fabrician genera as Lyccena^ Colias, Hesperia, 

 &c., which are, if anything, even more open to that objection. 

 But in the present instance there can be no doubt whatever 

 as to what Hiibner meant by his genus Byblia, for he cites 

 B. ilithyia, Drury, as its sole representative, which seems to 

 me to be as clear a definition as we can expect under the 

 circumstances. 



A careful examination of the long series of specimens in 

 the British Museum, which are there divided into no less 

 than seven species, has convinced me of the truth of 

 Mr. Roland Trimen's opinion that all the Asiatic and conti- 

 nental African forms of Byblia are referable to a single 

 species. Moreover I agree with M. Mabille in refusing 

 specific rank to the Madagascar form, which, however, I do 

 not regard as a mere variety, but as a subspecies, taking that 

 term to signify a clearly localized variety, which does not 

 occur in company with the type-form, but completely replaces 

 it within a defined area, though still exhibiting sufficient 

 intergrades linking it to that form to prevent its being re- 

 garded as a distinct species — in other words, a geographical 

 race. The following is the synonymy of the single species 

 and its various forms : — 



1. Byblia ilithyia (Drury). 



Papilio ilithyia, Drury, 111. Ex. Ent. ii. t. xvii. tigs. 1 and 2 (1773). 

 Papilio ilithuia, Fabr. Spec. Ins. ii. p. 97 (1781). 



