AQUATIC INSECTS IN NEW YORK STATE 287 



liooks. A ventral pair of slender bristles under both meso- 

 "thorax and metathorax. 



There are stout ventral prolegs on abdominal segments 1-8, 

 paired on all the segments except the eighth, each with a double 

 circlet of hooks at its tip. On segment 1 each proleg is sim- 

 ple, with hooks directed posteriorly. On segments 2-7 each 

 proleg is divided at its apex, becoming double, with the hooks 

 on its two divisions opposed in position [pi. 10, fig.2]. On 

 the eighth segment there is a single median proleg with its 

 hooks directed forward, and at its base is a pair of low, broad 

 anal tubercles. There are two pairs of conic, fleshy tubercles 

 on each of segments 1-7 of the abdomen, one tubercle at either 

 side of the dorsum and a longer one at the middle of each side, 

 nil increasing in length posteriorly. The abdomen ends on the 

 ■dorsal side in a pair of long, fleshy processes, stout at base and 

 attenuate to apex, each with a lateral fringe of long hairs each 

 side, on the outer side the fringe extending on segment 8 nearly 

 to its base. Between the bases of these processes on the dor- 

 sum of the eighth segment is the single respiratory aperture — 

 a narrow median slit guarded by white lips, on a low convex 

 elevation. 



The most remarkable features of this larva are (1) the con- 

 formation of the caudal end of the abdomen, (2) the single res- 

 pirator}' aperture and (3) the paired and bifurcated prolegs with 

 their heavy armature of grappling hooks. This grappling appa- 

 ratus is doubtless correlated with a life spent clinging to the 

 surfaces of rocks in the current of rushing streams. 



A note on caddis flies described in Bulletin 47 

 The identity of the species described on p. 569-70 as " 3 Halesus 

 sp. ? " has been settled by the rearing of it by Mr Betten at 

 Lake Forest 111. It is Halesus hostis Hagen. Larvae, 

 in cases like the one shown in plate 33, figure 1 of Bulletin 

 47, were collected from a spring-fed rivulet late in August. 

 Pupae were found in the breeding cage soon thereafter, and a fine 

 male imago emerged on Sep. 23. 



Two excellent German students of the Trichoptera, Ulmer and 

 T\'eltner, simultaneously and very kindly sent information as to 

 the probable identity of the "' egg-ring of an unknown caddis fly " 

 figured on plate 33 of Bulletin 47. Similar egg masses are laid, 

 they say, by the European species Phryganea grandis 

 and Phryganea striata, and this one may well have 

 belonged to our Phryganea cinerea Hagen. 



