C4. H. Ford 105 



On the underside of the head, adjacent to the first maxillae, is a 

 dark, strongly-chitinised ridge, diverging anteriorly and converging 

 posteriorly. A dark line runs parallel, close to the preceding ridge. 



The prothorax has a curved furrow running down each side, and is 

 nearly equal in length to the meso- and meta-thorax taken together. 

 The hairs on the body of the larva are arranged in a definite manner, 

 which seems to be fairly constant. The first eight abdominal sterna 

 each possess three pairs of hairs, arranged symmetrically along the 

 margins of these sterna. On examining the larva in its lateral aspect, 

 it is seen that the first eight abdominal terga, considered up to their 

 mid-dorsal line, possess two lateral pairs of hairs ; of which the posterior 

 pair is placed near the margin, a little to the left of the plane of the 

 anterior pairs, which are placed nearer to their margin than the former. 

 Placed mid-laterally, and just over each spiracle (of the first eight 

 abdominal segments), is a pair of short hairs about half the length of 

 the other hairs. In a line with the spiracle and in the same plane as 

 the two posterior hairs, is a single hair of similar length to the paired 

 ones. The ninth abdominal segment bears, on the base of the pseudo- 

 podium (or anal papilla), two pairs of short hairs. There are nine 

 pairs of spiracles, the first being thoracic (Plate XYI, fig. 2, st), and 

 placed ventrally. The remaining eight pairs are laterally placed on 

 the first eight abdominal segments anteriorly in each segment. The 

 ninth abdominal segment affords a means of distinguishing the genus 

 Agriotes ; Perris (14) describes the typical anal segment of the genus as 

 follows: "Dernier segment assez-longuement demi-ellipsoidal, termine 

 par une pointe, ayant de chaque cote, pres de la base, une cavite de 

 I'apparence d'un grand stigmate." 



This applies truly to the larva of Agriotes obscurus, but requires to 

 be added to. The anal segment is terminated by a slight constriction, 

 which swells out into a blunt point, outlined in black (Plate XVII, figs. 

 5 and 6). The cavity, that Perris describes as being like a large stigma, 

 is not a respiratory opening, but is possibly a muscle attachment^. 

 The walls of the cavity are black, and thickened ; only slightly at the 

 sides, but strongly dorsally and ventrally. In shape it is oblong, with 

 the anterior and posterior walls rounded. It is placed very high up, 

 and near the base of the segment. The stigmata are oblong, with 

 their dorsal and ventral walls closely apposed, and strongly chitinised ; 

 their median line points forward and upwards, save in the case of the 

 meso-thoracic stigmata, where the median line points forward and 



^ Henriksen (8) also .speaks of this structure as an '"ej'e-shapcd muscular impression.' 



