

344 Dr. 'V. A. ('n;i[)iiiair.s Furtlier Notes on 



120 ', and ot" the flat suifaccs of t lie wings of about 110°; 

 the costae not being so far advanced as to be in a ])lane 

 transverse to the line of the insect body, but behind this 

 in a plane that slopes backwards from it at a consider- 

 able angle. This position, which aj)pears to re[)resent the 

 memory of the normal (triungniar) resting attitude of Geo- 

 meters, may last about thirty minutes, and in another 

 thirty minutes the wings close again dorsally to a costal 

 angle of about 45°. At this point the costae of the fore- 

 and hind-wings on either side are nearly coincident. 



In the same gradual imperceptible way in which the 

 other movements occur, the fore-wings advance from the 

 hind-wings. Measured from costa to costa at the post- 

 discal line it takes about two hours for the fore-wings to 

 be 3 mm. in advance of the hind-wings, the fore- and 

 hind- wings being still in the same plane. Then, still 

 very gradually, the fore-wings assume the curious bend in 

 a line below vein 2 that characterises the ordinary 

 resting attitude of the species, the inner part of the wing 

 being in the same plane with and close against the hind- 

 wing, the greater (costal) portion being raised at a con- 

 siderable angle. At the end of another hour one may 

 think this attitude is attained, at the end of two one has 

 no doubt it is. All the i)rogress and the movements 

 involved are so gradual and imperceptible that it is difficult 

 to divide them into stages and say when each is complete. 



Illuslraria emerges in the morning about 6.30 to 7.30 

 a.m. 



Emiomos lunaria. The wings are thrown back when 

 expanded, and some ten minutes later and when appar- 

 ently dry are opened gradually, so that in about six minutes 

 they nearly approach a fiat position, instead of 180^ (flat), 

 between the two fore-wings they are about 160° or 170°. 

 In some ten minutes the angle diminishes to that of normal 

 resting, perha])s 80°, but there is still no angulation of fore- 

 wing, and the hind-wing is only 3 or 4 mm. behind 

 fore-wing. The complete resting attitude with fore-wing 

 advanced and with the longitudinal fold is not attained 

 till an hour or two later. I see that in one specimen I 

 noted the wings were opened till quite flat ; in another 

 they did not get quite as far, but I did not note the angle. 

 The costae of fore-wings made an angle of 90°, but the wing 

 surfaces were much more. 



Fidonia piniaria emerges 6 to 8 a.m. The wings expand 



