GEOMETRIDAE. 



159 



times the strongest and blackest of all the markings (fig. 11) or developed into 

 a band (fig. 2). Even the tendency shown in some of the allies {e.g. C. 

 injectaria Walker and C. immemorata Walker) for this strong median line to 

 throw out a longitudinal branch across the postmedian in front of R 3 occa- 

 sionally manifests itself (fig. 15), or is indicated by blurred or diffuse darkening 

 (fig. 3). As regards the general distribution of the colours, there is endless 

 variation ; definitely banded forms may have the median area white and the 

 rest dark or red-brown (cf. figs. 7 and 17), or — at least on the fore wing 

 and anterior part of the hind wing — the antithesis of this, the median area being 

 blackened and the rest more or less pale (see fig. 1) ; or the white areas may 

 be partly suffused (figs. 4, 13) or more proximal (fig. 11) or more restricted 

 (fig. 3), or — somewhat similarly — a dark central band may be restricted to the 

 area between median and postmedian. An extreme, rare ab. (fig. 6) is almost 

 entirely blackened, leaving only the base and apex of the fore wing pale. One 

 (not figured) has the cell-spots abnormally enlarged. Other phases of varia- 

 tion, which it is impossible to discuss in detail, may be gathered from a study 

 of the plate or of the general tendencies of the polymorphism known in the 

 other most variable Indo-Australian Chora — inflexaria Snellen. 



Finally, mention must be made of some teratological variations. Apart 

 from the very great discrepancies in size — ranging from 30 mm. or less up to 

 46 mm., and apparently not seasonal — there are occasional deviations from the 

 normal shape. Particularly curious is the fine $ aberration (pi. V, fig. 11) 

 in which the right fore wing is somewhat shortened, and the right hind wing 

 definitely enlarged. In a somewhat analogous aberration of the with broader 

 black median shading, both hind wings are somewhat produced in the middle, 

 though not absolutely symmetrically. 



Concerning the probable origin of C. samoana, little can be said. It has 

 nothing directly to do with C. " acaciaria," nor even with C. alienaria Walker, 

 the species which Hampson (Faun. Brit, hid., Moths, iii, fig. 137, 1895) figures 

 under that name ; probably Rebel (loc. cit. supra) was misled by Hampson's 

 absurd " lumping," and made no independent investigation. From the rather 

 narrow wings, prevalence of brown colouring, pronounced outward curve of the 

 postmedian of the fore wing at the radials (one of the very few comparative 

 constants in its scheme), and strongly clouded or banded under side, one might 

 have supposed it to be a representative, if not even a subspecies, of C. injectaria 

 Walker, but the genitalia do not altogether bear out this assumption. I can 



