. Bulletin - New York State Museum. Science. 436 NEW YORK STATE MUSEUM very close together so that they appear as one. The first three segments in specimens which are ready to transform are en- larged and represent the thorax; the intermediate segments are subequal in length and apparently without trace of setae. On the ventral surface of the 11th are two pairs of long blood gills [], on the caudal end of the dorsal aspect of the last segment are two tufts of five or six long hairs; ventrad of which is a bunch of four very short processes. The anal feet are about as long as the 11th segme
. Bulletin - New York State Museum. Science. 436 NEW YORK STATE MUSEUM very close together so that they appear as one. The first three segments in specimens which are ready to transform are en- larged and represent the thorax; the intermediate segments are subequal in length and apparently without trace of setae. On the ventral surface of the 11th are two pairs of long blood gills [], on the caudal end of the dorsal aspect of the last segment are two tufts of five or six long hairs; ventrad of which is a bunch of four very short processes. The anal feet are about as long as the 11th segment, each one with a crown of 12 to 15 bifid claws, resembling the one shown on plate 50, figure 9, but sharper, straighter and more slender, and the inner one comparatively shorter, the angle between the two teeth being about 60°. The pupa [] is elongate, its abdomen eight segmented, not counting the anal appendage. The usual respiratory fila- ments of Chironomus, consist of a pair of much branched tufts. On the lateral margins of each of the segments are a few deli- cate, transparent filaments []; of these there are five pairs on the eighth segment, besides a pair of chitinized toothed claws. On the margin of the anal segment is a close row of hairs, the basal portions of which are stout, but extremely fine at the extremitv, where thev become matted, forming a paddle [,12]. Of course no adults were found in the material, but from some nearly mature pupae the flies were withdrawn, and these possess the following characters. Length, 7 to 8 mm. Dorsum of thorax brown, with the usual three dark dorsal stripes; pectus darker brown; dorsum of abdomen paler brown, the incisures whitish; the ventral surface of each segment with a large, rectangular brown spot, the rest whitish; legs yellowish brown; the tips of all joints blackish. Metatarsus longer than the preceding joint; all tarsal claws simple. Male genitalia complex, consisting of two pairs of blunt lobes, the
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1887
