278 Mr. L. B. Prout on new G-eometridfe 



point of distinction between g. gracilis and its more southerly 

 races is the absence of black costal dusting on the proximal 

 part of the fore wing in the latter ; in g. gracilis the costa is 

 black or blackish to the base. Except at. the base and on 

 the hind wing g. landbecki is individually very variable; the 

 pale fulvous shade may disappear before one-third of the 

 costa, and not reappear, or it may reappear as an isolated 

 spot in the region of the distant areole, or with a large spot 

 at base of veins B^-M 1 , or it may run broadly to beyond 

 middle of costa, becoming confluent with the last-named spots 

 (name-type), and there may even be a further extension of 

 the outer spots into an irregular band proximal to the black 

 border and reaching SM 2 . 



Upper Kasai District, Congo Free State (P. Landbeck) ; 

 7 S 6 in coll. Joicey. 



It may be pointed out that landbecki, Druce (Ann. & Mag. 

 Nat. Hist. (8) vi. p. 400), wrongly described as an Aletis, 

 and cited there by me in Lep. Cat. viii. p. 79, is a Mimahtis 

 (subfamily Geometrinaj), so that there is no fear of collision 

 in the use of this subspecific name. 



Subfam. Hemitheinm. 

 2. Thalassodes clarifimbria, sp. n. 



? .—42-49 mm. 



Face reddish brown. Palpus somewhat more reddish, 

 beneath yellow-white ; third joint relatively short, about half 

 as long as second. Vertex and antennal shaft white; occiput 

 green ; thorax and abdomen green above, unmarked ; beneath 

 white to whitish. 



Fore wing green, rather duller and bluer than in semi- 

 hyalina, Walk., the white strigulation rather strong ; costal 

 edge yellow at extremity, then whitish ; lines white, rather 

 faint, obsolete costally ; antemedian placed as in the allies; 

 postmedian rather far from termen anteriorly, reaching 

 hind margin at two-thirds; fringe almost white. 



Hind wing with termen more feebly bent at E, 3 than in the 

 allies, excepiing perhaps semihyalina ; concolorous with fore 

 wing, the elongate cell-mark and the postmedian lino both 

 present, but lather indistinct. 



Underside paler green, almost unmarked ; fore wing with 

 costal edge pale yellow ; both wings with fringe whitish. 



Ceylon: Maskeliya, Aug. 1905 (type) and June {O. C. 

 Alston), in coll. Joicey ; Hakgale, April 1907 (E.E. Green), 

 in coll. Brit. Mus. ; the latter yellower green, perhaps faded. 



Distinguishable from the allies by the whiter fringes and 



