Abstract
Pseudodiamesa arctica (Mall.), Heterotrissocladius subpilosus (Kieff.), Orthocladius (s.s.) lapponicus Goetgh., Orthocladius (s.s.) sp., Paracladius quadrinodosus Hirv., Trissocladius tricornis n. sp., and Lauterbornia sedna n. sp. develop from egg to pharate adult in Char Lake. The occurrence of the larvae of 7 additional species is apparently adventitious, All stages of the two new species plus the larvae of P. arctica and P. quadrinodosus are described. The males of T. tricornis are dimorphic and L. sedna is parthenogenetic. New distribution records are given for most of the species. The chironomid fauna of Char Lake is compared with that of other arctic lakes.