TRIFID.E. 297 



white. Others from the same district are darkened with a 

 smoky suffusion. In Yorkshire this last jDhase of variation 

 becomes much intensified, and replaces the usual pale forms 

 almost entirely, so that many specimens are as dark as 

 Acronycta megaccphcda and bear a most curious resemblance 

 to it. In the collection of Mr. G. T. I'orritt is a still more 

 extreme form, from the same district, its fore wings being 

 wholly suffused with smoky-black, with the exception of the 

 four pale transverse lines and the pale dashes in the cilia, all 

 of which are of a clear yellowish-white. There is also much 

 variatiou in the depth or absence of colour in the hind wings, 

 and they do not by any means always follow the fore wiugs 

 in this respect. 



On the wing- in September and October. 



Larva cylindrical and moderately stout ; the head full and 

 but little narrower than the second segment, the segments 

 very smooth and scarcely defined when the larva is stretched 

 out, though when it turns round the skin folds itself at some 

 of the segmental divisions and then shows distinctly pale 

 yellow in the folds. Ground colour bluish-green or yellowish- 

 green ; a slightly darker dorsal line has a series of minute 

 yellowish dots or specks through its middle ; spiracular line 

 dark green or blackish-green, but is only a mere edging to 

 a yellowish-green sub-spiracular stripe, which melts away 

 gradually below into the green of the undersurf ace ; spiracles 

 white, outlined with black ; the ventral surface of the same 

 green as the back, and has a faint central whitish stripe ; 

 legs and prolegs clear green ; all the rest of the green surface, 

 except the head, and a smooth velvety plate on the second 

 segment, minutely freckled with atoms of whitish-yellow, a 

 few more distinct than the rest marking the subdorsal line in 

 an inconspicuous manner. (W. Buckler.) 



April or May to July, on chickweed, groundsel, mint, rag- 

 wort, mugwort, dock, plantain, honeysuckle, everlasting pea, 

 fox-glove blossoms, and other hei'baceous plants, and on ivy, 



