| | PAGE |
| Fig. 1. Bombus, larva and nymph: after Packard | 11 |
| ,, 2. Ammophila | 22 |
| ,, 3-4. Spines on the tarsi of female Ammophila | 23 |
| ,, 5. Tubular entrance to hole of wasp | 25 |
| ,, 6. Basal segments of ants | 33 |
| ,, 7. Rose-leaf partially eaten by bees | 52 |
| ,, 8. Tufted hairs of hind leg of Andrena | 67 |
| ,, 9. Corbicula of humble bee | 67 |
| ,, 10-12. Cleaning apparatus of bees | 69 |
| ,, 13-18. Hairs of bees, magnified | 71 |
| ,, 19. Tongues of bees, magnified | 73 |
| ,, 20. Diagram of tongue of bee | 75 |
| ,, 21. Stylops | 77 |
| ,, 22. Stylops larva in abdominal cavity of bee | 78 |
| ,, 23. Antennæ of "Keyhole" wasps | 101 |
| ,, 24. Legs of male "Keyhole" wasps | 101 |
| ,, 25. Tibia of male Crabro cribrarius | 103 |
| ,, 26. Antennæ of male Crabro cribrarius | 103 |
| ,, 27. Head of male and female Crabro clypeatus | 103 |
| ,, 28. Parts of the insect | 133 |
