THE GENUS ACRONYOTA AND ITS ALLIES. 27 



The youn,e^ larva is of typical Acronycta form and colour, in 

 all the five British species being very nearly alike, and very close 

 to the newly-hatched larvae oi psi and tridens, having the 2., 

 3.4, 6.7, lo.ii, and 13th segments pale, differing from the 

 other groups in having three or more hairs on the anterior 

 trapezoidal tubercles. The full-grown larva tends to be hairy 

 by having many hairs on the tubercles, the rest of the larva 

 being comparatively free ; auriconia and menyantJiidis are typical 

 in this respect. 



The pupa is (with the disposition of the eggs) the most dis- 

 tinctive character of the group. It is black or nearly so, of a 

 rough, wrinkled, and warty surface ; the free abdominal segments 

 (segments g and 10) are of as wide, or even wider a diameter 

 than those in front of them, the tapering to the tail being done 

 in the remaining fixed segments 11-14, giving a peculiar 

 squareness to the pupa. There is a double nodule between 

 the eyes ; the posterior margin of each segment, most marked 

 in 9 and 10, has a raised band, just like those barrel hoops 

 that are made of a branch split and with the bark left on, 

 whose smooth surface contrasts with the roughness of the rest 

 of the segment. In many pupae (Noctu^ and others) there is 

 a tendency for this margin of the segment to be free from pits or 

 points, and in some a slight tendency to be raised above the 

 general level, but nowhere else does it assume so distinct a 

 barrel hoop form as in ruinicis and venosa. The anal armature 

 is a projection with somewhat quadrangular termination having 

 the points or spines nearly or quite obsolete, but clothed with a 

 brush of stiff brown bristles (Plate L, fig. i, pupa oi niviicis) . 



This pupa is enclosed in a cocoon of tough, whitish silk, 

 fairly copious in amount, but of one simple layer, usually 

 clothed in fragments of grass, twigs, leaves, etc., and often 

 placed against a stump, stone, or post. 



The second, or psi group, I propose to call by the name 

 Cuspidia {cuspis, a spine), as the pupae are distinguished by a 

 peculiar arrangement of long terminal spines {vide Plate I., fig. 

 2). In this section the eggs are always laid separately and, so 

 far as I know, in the wild state, are laid solitarily. They arc 

 not quite so flat as those of Vimiuia. Being laid solitarily, they 

 assume their natural dome shape, whilst those of Vimiuia being 

 laid overlapping each other, and consequently not on a flat 

 surface, take whilst soft a form in which some of the convexity 

 affects the lower surface and are therefore flatter above ; essen- 

 tially probably the eggs in both groups are equally dome shaped ; 



