- Lapland Longspur
- Lapwing ( Vanellus cristatus )
- Large-headed Turtle
- Lark Sparrow
- Larva of a flesh fly (Sarcophaga) - Caudal aspect - Anterior stigmata. Pharyngeal skeleton
- Larva of Anopheles
- Larva of Auchmeromyia luteola
- Larva of Fannia scalaris
- Larva of Forficula
- Larva of Pulex irritans
- Larva of Simulium
- Larva of Xenopsylla cheopis
- Larval Stages of the Common Rock Barnacle (Balanus balanoides
- Larval Stages of the Common Shore Crab
- Last Larval Stage of the Common Porcelain Crab
- Leaf-Cutter Bee at Work
- Leatherback turtle
- Left hand stigmata of the larvæ of muscoidea
- Left spiracle of nymph of Argas persicus
- Legoean
- Lemming
- Lemon
- Leodice sanguinea
- Leonardo Da Vincis diagram of the heart
- Lepismas at Work
- Leucadendron Stokoei
- Leucadendron Stokoei
- Life cycle of the malarial parasite
- Light White and Sandy She-Cat and Kittens
- Lilies
- Lily
- Lily and Rose
- Limulus cancriformis
- Linguatula. (a) larva; (enlarged). (b) adult; (natural size)
- Lion
- Lion
- Lion by Alfred Stevens
- Lion Divider
- Lion from a Theban bas-relief
- Lion from Assyrian Bas-relief
- Lion, supporting the pillar of the Pulpit, St. Mark’s
- Lioness
- Lioness
- lioness
- Lioness and young, from an Ionian vase of the sixth century B. C
- Llama
- Llama
- Loaded-up Camel
- Lobster
- Locust
- Loggerhead Shrike
- Long Eared Owl
- Long Haired cat
- Long Haired Cat 'Tiger'
- Long haired kitten 'Chloe'
- Long Haired Persian
- Long Haired Persian 'Bogey'
- Long Lost Found Again
- Long-armed Tarantel Scorpion
- Long-eared Sunfish