449 



not occur in the localities where Garman collected, so far as our in- 

 formation goes, together with the fact that his No. 4 specimens do not 

 agree with Johannsen's description, virtually proves that they can not 

 be plumosus. It is almost certain that the species is tentans, the larva 

 of which has not been definitely associated with the pupal and imaginal 

 stag:es in connection with the work of this Laboratorv. 



'&^ 



29. Chironomus viridis Macquart 



Chironomus viridis Macquart, Suites a. Buflfon, 1834, Vol. 1, p. 52. sp, 21. 



Larva. — Length, 10-12 mm. Green, thoracic and last three ab- 

 dominal segments reddish or brownish. Head slightly longer than 

 broad; antennae slender, basal joint about one and two thirds times as 

 long as the remaining joints, second joint as long as the next two to- 

 gether, the other joints increasing in length to apex; labium as in Fig- 

 ure 2, Plate XXIX, the teeth very distinctly blackened ; transverse 

 fringe of epipharynx consisting of a central portion with five teeth, 

 and another each side with generally three teeth on each ; mandibles 

 with four teeth, inclusive of the apical one, which are distinctly black- 

 ened, the usual hairs present. Apices of anterior pseudopods armed 

 with soft hairs ; abdominal segments without noticeable hairs ; dorsal 

 tufts consisting of about ten hairs, the basal papillae very short; two 

 long hairs above the bases of the upper pair of blood-gills; anal pseu- 

 dopods with strongs brown claws at their apices ; ventral blood-gills 

 absent. 



Pupa. — Length, 8-9.5 ^"^- Color very similar to that of larva. 

 Frontal tubercles absent ; thoracic respiratory organs with many white 

 hairlike filaments. Dorsal surface of abdomen with a transverse row 

 of numerous closely placed pale brown setulae near the base of seg- 

 ments 2-6 (PI. XXXI, Fig. 8, a, h, c, d), another row near apices of 

 same segments, which becomes gradually less distinct on the last three 

 of these segments and is sometimes interrupted at the middle, and the 

 normal apical row of distinct, black, thornlike setulae at apex of second 

 segment (Fig. 7) ; lateral apical process on segment eight with about 

 eight short leaf like apical thorns (Fig. 6) ; apical processes of abdo- 

 men as long as eighth segment, their outer margins with numerous 

 long, flattened hairs. 



Imago; Male. — Bright green. Head green; antennae yellow, fla- 

 gellum and plumes brown. Thoracic vittse, a spot below wing-base, 

 the sternopleura, and postnotum reddish or yellowish. Abdomen gen- 

 erally entirely green with the hypopygium yellowish. Legs greenish 



