Lateral line system, [261], [355], [411], [470]

Law of Progress, [19]

Lw" of Recapitulation, [434], [456], [498]

Layer, germinal, [459]

Lay"r, laminated, [347], [348]

Leech, [421]

Lens, formation, [83], [115]

Lepidosiren, [148], [461], [466]

Limulus or king-crab, [25], [140], [236], [240]

Liml"us appendages, branchial, [138], [164], [175]