1944] Genus Lycceides 115 
the disappearance of the veins that had once halved their cells. 
In the forewing the last radial is numbered R 4 since I have 
not come to any conclusion as to which of the initial five 
veins disappeared. The stalking of R 3 and R 4 seems to have 
occurred after the (rare and weak) first and second macules in 
R 3 reached their present position from a point adjacent to cell 
RM ; their weak condition seems due to the subsequent segrega- 
tion in the prison of the shortened and narrowed interspace. 
An examination of all known genera of Lycaenidae, clues 
provided by aberrational individuals and certain ontogenetic 
data suggest that the maculation of a given interspace develops 
phylogenetically in result of a series of recurrent waves or rays 
of pigment, each shorter than its predecessor. An initial wedge- 
like or gusset-like infuscation, in the proximal corner (against 
cell RM) of a neutrally colored interspace, grows distad, ex- 
tending along the interneural fold. This ray broadens distally; 
the limit (and transverse breadth) it attains varies, and this 
variability is responsible for the variable position and inter- 
neural breadth (filled completely in “striped” forms) of the 
subsequent macule. The latter is formed by a gradual deepen- 
ing and concentration of the fuscous pigment at its maximal 
distal limit, which in the case of the first macule to be evolved, 
is subterminal. The rest of the fuscous extension is weakened, 
owing to this local concentration, and finally degenerates and 
disappears, leaving only the residue of its distal limit and the 
initial wedge-shaped store of fuscous in the proximal corner, 
whereupon the whole process is repeated (in the majority of the 
Lycaenidae). It is repeated with a little less vigour but with 
more variety in the limit of the fuscous extension and hence in 
the position and size of the second macule which is formed 
discally in the same way as the first was formed subterminally. 
In some interspaces the number of which varies in the Lycae- 
nidae, a proximal wedge still remains, even after the termina- 
tion of the second process. At this point it may not have suffi- 
cient strength to extend again but a certain concentration of 
fuscous does occur, with the formation of a half halo distally, 
(see halo), this gusset-like macule appearing to the eye as a 
sessile third macule ready to emerge completely and creep in 
the wake of the second one. However, in certain interspaces a 
third wave of fuscous may extend as freely as it had done in the 
second process and a third macule is formed more or less dis- 
