Krause, on parasites, [163]

Krohn, on Nemertine development, [99]

Krohnia, [186];

species, [192], [194];

American species, [534]

Krukenberg, on haemerythrin, [416]

Kynotus, [386]

Labrorostratus, [297]

Lacinularia, [200], [213], [215], [221], [226]

Lacrymaria, [235]