NONAGRIA SPARGANII. 45 



and enters therein, it throws out to some distance 

 from the hole a quantity of pale " frass " during the 

 first day or two, according to the size of the larva, 

 but afterwards allows much to accumulate within the 

 mine, where, turning to a darker colour, this often 

 shows through the leaves when they are seen against 

 the light ; but when the stem is entered the larva 

 mines downwards, and ejects all " frass " from the 

 mine, which throughout its length is of a diameter 

 little more than that of the larva itself. There, a little 

 below the entrance, the larva gnaws out a narrow and 

 deep channel horizontally in the circumferent pith 

 near to the outer cuticle, and another similar channel 

 near the bottom of the mine. 



In order to observe the natural habits of the larvae 

 it was necessary to have a number of the plants, grow- 

 ing in pots with plenty of water, in the open air for 

 them ; but at length, when too late, I found my con- 

 fidence had been misplaced in allowing the larvae too 

 complete freedom, for it resulted eventually in the 

 escape of all but three. Notwithstanding this mishap, 

 I was lucky enough to have one turn to a pupa on 

 August 11th, and another on the 15th; the other larva 

 in captivity was supplied continually with fresh-cut 

 pieces of Iris standing in water, and fed well to the 

 end of the month, but afterwards wandered about, re- 

 fusing to make up for pupation, until it died, the very 

 day on which the first pupa disclosed a fine example 

 of the moth, at 4.35 p.m., September 10th. 



The young larva, when no more than three-quarters 

 of an inch in length, was remarkably slender, very 

 translucent and tender-looking, of a pale watery 

 greenish tint, with pale brownish head, and plate on 

 the second and anal segments, having on the body 

 four fine longitudinal stripes of light olive-brownish 

 or greenish, the spaces between them being slightly 

 paler than the pale belly. This design continued to 

 be developed with an increase of colour and distinct- 

 ness in proportion to growth ; the substance of the 



