The pupa resembles the adult to some extent; however, the pupa retains 

 some characters of the larva (e. g., gills) and has specific organs present 

 in the pupal stage; such are the clinging and cleaning apparatus of the pupa, 

 its swimming organs and the labrum and .mandible, which have a different 

 function from those of the larva. 



M o r pho logy 



Head. The head is small, broad and orthognathous; its dorsal side is 

 convex. There are large eyes on the sides. The antennae are as long as 

 in the imago and are directed posteriorly, along the body; if the antennae 

 are longer than the body, their ends are coiled around the last abdominal 

 segments. 



88 



FIGURES 132 and 133. lst-stage larvae of Limnophilus nigriceps in 

 temporary cases: 



132 - Anteclypeus and labrum of Mystrophora altaica (A),andPo- 

 tamophylax nigricornis (B); 133 - mandible ofMacronema 

 r ad i a turn: dorsal view of left mandible (A), ventral view of right man- 

 dible ofOdontocerum albicorne (B), dorsal view of right mandible 

 of Potamophylax nigricornis (C), dorsal view of left mandible of 

 Sericostoma pedemontanum(D) (132, B, 133, B-D - after Nielsen). 



80 



