摘 要 ：The identity of Polypodium clathratum Clarke（Lepisorus clathratus Ching）has been established and the confusion into which it has been thrown for a century has been clarified by the present study，which reveals for the first time that the species as heretofore accepted by different authors since the time of Cl－arke is a complex consisting of over a dozen distinct but superficially related pecies in the Sino-Himalayan region as far as Japan to the east，while L．cla-thratus（s．sir．）is confined tothe Himalayas only．
Abstract:The identity of Polypodium clathratum Clarke（Lepisorus clathratus Ching）has been established and the confusion into which it has been thrown for a century has been clarified by the present study，which reveals for the first time that the species as heretofore accepted by different authors since the time of Cl－arke is a complex consisting of over a dozen distinct but superficially related pecies in the Sino-Himalayan region as far as Japan to the east，while L．cla-thratus（s．sir．）is confined tothe Himalayas only．