100 [October. 



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 : hut, 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, growing in pots w'ith plenty of water, 

 in the open air for them — but at length, when too late, I found my 

 confidence 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 wan- 

 dered about, refusing 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 

 long, is 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 continues to be 

 developed with an increase of colour and distinctness in proportion to 

 growth ; the substance of the larva, when it is about an inch and a 

 quarter to an inch and a half long, is considerable, though still slender; 

 the stripes stronger, brighter, and fuller green, yet somewhat of a 

 transparent nature, for when folds of skin occur at the segmental 

 divisions, as they do when the larva is not stretched to its full extent, 

 the stripes on the folds appear darker and the pale interspaces paler. 



The full-grown larva when extended is about one and seven-eighths 

 to two inches long, and very slender, with all the legs fairly well de- 

 veloped, very cylindrical and uniform in substance throughout the body, 

 the head is of a full roundish form, broadest in front, glossy and of a 

 pale brown colour with still paler papillae, the mouth darker brown, and 

 ocelli black ; the plate on the second segment and that on the anal flap 

 are also pale brown and glossy ; the ground colour of the back and sides 



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