44 NONAGRIA GEMIN1PUNCTA. 



length of the abdomen, which had its segments well 

 divided, and was tapered off gradually to the tip ; 

 the pupa skin rather smooth, but with little polish 

 excepting in the abdominal divisions ; its colour a 

 dark purplish-brown on the thorax and wing-covers, 

 not quite so dark on the abdomen. 



The interior of the reed stem in which the pupa lay 

 was smooth, and of an opaque, deep, sooty-brown 

 colour, but without any lining of silk. (W. B., 27, 12, 

 73; E.M.M., X, 230, 1874.) 



NONAGRIA SPAEGANII. 



Plate LXI, fig. 3. 



I have to express my thanks to Mr. Sydney Webb 

 for his kindness in not only supplying me with this 

 larva, but also for details of its habits, which, by ob- 

 servation, 1 have been able to verify completely, for 

 the purpose of the following description undertaken 

 at his request. 



From the end of July to about the middle of August 

 these larvae, in various stages of growth, may be found 

 within the lower compacted parts of the leaves of Iris 

 pseudacorus ; sometimes two in one plant, but more 

 frequently only one, where it will have the tender 

 young central leaf in the very heart of the plant to 

 feed on. It often migrates, however, not only from 

 the leaves of one plant to another, but sometimes 

 enters the culm or seeding stem, where, after feeding 

 on the central pith down almost to the root, it retires 

 to attack another plant, and when about half grown 

 it frequently acquires a taste for Sparganium ramosum, 

 inhabiting therein the basal part of the trigonous leaf ; 

 or sometimes it enters the stem of Typha angustifolia, 

 though in whichever plant it happens to be when full 

 fed, there it remains in a perpendicular position, and 

 changes to a pupa. 



When a larva gnaws a hole in a fresh plant of Iris, 



