HYDR^CIA MICACEA. 51 



HYDR^SCIA MICACEA. 



Plate LXII, fig. 4. 



On the 22nd of June, 1869, I received from the 

 Hon. T. de Grey a larva which proved to be that of 

 this species, and, more recently, the following note : 



11 1 first observed the larva by pulling up, on the 

 14th May, a sickly-looking plant of Equisetam arvense. 

 It appeared to be feeding on the root and stem below 

 the surface of the ground, but when placed in a bottle 

 with a supply of the food-plant, it immediately entered 

 a stem, and fed upon the inner substance, hollowing it 

 completely out, and ejecting the frass at the lower end. 



" The larva moved readily from one piece into ano- 

 ther, and throve upon this food till May 28th, when I 

 supplied it with Equisetum fluviatile, on which it fed 

 well till June 21st," 



On arrival this larva was an inch and one-sixteenth 

 in length, rather slender, cylindrical, and tapering just 

 a little at the posterior extremity, its head as wide as 

 the second segment, the upper lip and mandibles 

 large, the transverse folds and segmental divisions 

 rather deeply cut. 



The colour of the back and sides down to the spira- 

 cles was a rather deep purplish red-brown, without 

 gloss, and a little paler on the thoracic segments and 

 at the divisions ; the sides below the spiracles, the 

 belly, and the legs were paler, and of a dingy flesh- 

 colour; the head ochreous-brown, and mandibles 

 blackish-brown ; a polished pale ochreous-brown semi- 

 circular plate on the second segment, rather broadly 

 margined in front with blackish-brown ; a small shining 

 pale ochreous plate on the anal tip, having a terminal 

 border of very small dark brown warts ; the other 

 tubercular warts arranged in the situation usual in 

 stem feeders, also blackish-brown in colour, and each 

 emitting a fine hair ; the spiracles black ; the prolegs 

 tipped with brown. 



