Dec, I9I3-] Tilbury: Notes on Chironomus cayug^. 



307 



The grown larva is blood red in color and ii to 12 millimeters in 

 length. The antenna is short, consisting of one main segment two 

 thirds of the whole length, bearing two other parts, one slender and 

 unsegmented, and the other divided into three unequal segments (fig. 

 d). The eye consists of two distinct spots on the side of the head. 

 The larva is free from setae except six microscopic ones on the top 

 of the head and two on the thorax. The mandible is rather large, 



(a) Lateral view of larvae showing two kinds of blood gills, (b) Border of 

 labium of larva, (c) Larval mandible, (d) Larval antenna, (e) Egg mass 

 (details, in part, omitted.) (/) Pupa not wholly withdrawn from the old larval 

 skin, (g) Caudal end of pupa showing tail fin and lateral spine, (h) One of 



the three thoracic gill tufts. 



with three prominent black teeth (fig. c) . The labium has a black- 

 ened edge with a three-lobed tooth in the middle and a pair of closely- 

 united teeth longer than the middle one, together with four other 

 shorter teeth on each side (fig. b) . On either side and a little below 

 the labium is a prominent row of seta;. The anal blood gills on the 

 eleventh segment are present and those on the twelfth segment are 

 rather long and rounded (fig. a). 



The pupa is blood red at first, like the larva, but soon takes on the 

 brownish color of the adult. The respiratory organ consists of a 

 cluster of three beautiful white plumes located on each side back o'' 



