IX. THE LARVA OF M I CRO M E RU S 

 LI NEAT US, BURM. 



By Major F. C. Fraser, I.M.S, 



(With Plate XXIII). 



Head ; the central part of eyes projecting slightly, this part 

 alone being facetted and therefore probably the only functional 

 part during the larval stage ; the antennae with a very long pedicel, 

 as long as 2/5ths the whole length of antennae, the base and tip of 

 the pedicel pigmented ; a strong, robust, backwardly directed horn 

 behind each eye; ocelli distinct in the final instar. 



Mask long and narrow ; median lobe deeply hollowed out and 

 moderately deeply cleft, the two corners of the cleft rounded and 

 overlapping; the free border of the lobe with blunt, tooth-like 

 crenations; lateral lobes bifid, each bifurcation bearing a strong 

 claw, the inner with a long moveable hook which overlaps its 

 fellow at the middle line. 



Prothorax with two forwardly directed, robust horns at the 

 anterior and outer part. 



Legs long and slender, practically free from hairs, the femora 

 adorned with four pigmented annuli. 



Abdomen twice the length of the wing-cases, moderately stout, 

 covered sparsely with short hairs and pigmented with a definite 

 pattern ; each somite bearing a row of closely-set, short spines 

 along the apical border. 



Caudal appendages only two in number, easily fractured off, 

 not functionating as gills, covered with short, stiff hairs, triquetral 

 in section, all the three surfaces being flat and the broadest below. 

 The two lateral surfaces meeting above to form a crest which is 

 furnished with two rows of short, stout, strongly imbricated spines. 

 Similar spines along the inner and outer borders. 



Habits: Always in fast running water, clinging to roots, 

 submerged twigs and other debris, rarely to the stems of weeds or 

 reeds. 



The exuviae of these insects are extremely common, being 

 found usually on the trunks of trees adjacent to streams, some- 

 times as high as seven feet above water-level, although generall}' 

 at not more than two. The living larvae are obtained with great 

 difficulty owing to their clinging so tightly with their long legs to 

 the objects mentioned above and at a comparatively great depth. 

 In Poona I have generally managed to obtain them by pulling out 

 submerged branches of trees and date-palm leaves which had fallen 

 into the water, but even here they were difficult to find on account 



