The paedogenetic male cycle in Salmo salar L

Abstract

Phenomena discussed under the following headings: (1) Introduction and Literature, (2) Phases of the gonads in parr and smolts, (3) Histology of the [male] gonad phases, (4) River temp. during the period of gonad development, (5) Spawning of [male][male] in successive yrs., (6) 2 types of [male] salmon smolt, (7) Character of scales in maturing [male] parr, (8) The older [male] parr in British rivers, (9) Mortality among spent parr, (10) Generality of the Paedogenetic cycle in the Atlantic [male] salmon throughout its distribution, (11) Acknowledgements, (12) Summary, (13) References. It is concluded that "The sex records given herein, along with those of ripe parr in the literature, leave no doubt that paedogenesis in the [male] of the Atlantic salmon occurs throughout its geographic range.".