CHAPTER VI.. Aquatic Insect Larvae 157

AQUATIC INSECT LARVAE 157

INDEX 189

LIST OF ILLUSTRATIONS

FIG. PAGE

Ptychoptera paludosa. Limnobia replicata Frontispiece

1. Hand Magnifier and Stand 14

2. Zeiss’s Dissecting Microscope 16

3. Leitz’s Dissecting Microscope 17

4. Two Leitz Lenses in holder (open) 18

5. Two Leitz Lenses in holder (closed) 18

6. Home-made Dissecting Microscope 19

7. Beakers 21

8. Glass Capsule 21

9. Glass Block, with cover 22

10. Glass Box, with cover 22

11. Forceps 23

12. Three forms of Dipping-tube. Method of using it 24

13. Mounted Needles 25

14. Cape Peripatus (natural size) 30

15. Margined Water Beetle (male) 32

16. Shells of Molluscs broken up by Dytiscus 33

17. Outline of Dytiscus 38

18. Male Dytiscus in flight 39

19. To show fold of (right) wing of Dytiscus 40

20. To show fold of (right) wing of Dytiscus 40

21 and 21 A. Head of Dytiscus 42

22. Disposition of mouth parts 43

23. Leg of Cockroach 44

24. Tarsus of Dytiscus (magnified) 45

25. Female Dytiscus swimming 46

26. Upper surface of abdomen of typical Beetle 47

27. Spiracle of Dytiscus (magnified) 48

28. Tracheal tubes of Dytiscus (magnified) 48

29. Great Water Beetle 51

30. Female Hydrophilus constructing a cocoon. (After Lyonnet) 55

31. Cocktail Beetle 58

32. Cockroaches 66

33. Mouth parts of a Cockroach 69

34. Cockroach, showing Spiracles 71

35. Alimentary Canal of Cockroach 73

36. American Cockroach (male) 75

37. Larva and Pupa of Earwig 77

38. Earwig (male) 78

39. Great Green Grasshopper (female) 81

40. Tibial ear of Great Green Grasshopper 85

41. Land Bug (magnified) 86

42. Water Scorpion 87

43. Organs of Water Scorpion, Egg, and Parasitic Mite. (After Swammerdam) 90

44. Raptorial leg of Water Scorpion 92

45. Water Boatman 93

46. Water Boatman swimming 94

47. Corixa, with wings expanded 95

48. Scheme of under surface of Wolf Spider (female). Pedipalp of male (enlarged) 98

49. Garden Spider and Web 99

50. Threads of Spider’s Web 100

51. Anchorage of Web 101

52. Foot of Garden Spider 104

53. Spinnerets of Garden Spider 104

54. Jumping Spider 106

55. Falces of Male Jumping Spider 106

56. Foot of Jumping Spider. Scopula much enlarged 108

57. Diving Spiders 109

58. Cell of Diving Spider 112

59. Red Water Mite 114

60. Larva of Water Mite 117

61. Nymph of Water Mite 117

62. Beetle Mite 119

63. Lithobius forficatus. Mouth parts seen from below. (After Graber) 124

64. The Common Millepede 126

65. Segments of Millepede (magnified) 127

66. Prawn 132

67. First walking leg of Shrimp (enlarged) 134

68. Mysis, or the Opossum Shrimp 135

69. Maxillipedes and Maxilla of Shore Crab. (After Savigny) 138

70. Stomach of Crab laid open 139

71. Gammarus. (After Sars) 142

72. Maxillipedes of Gammarus marinus (magnified) 146

73. Nest-building Amphipod (from life) 148

74. Water Woodlouse 153

75. Mouth-lock. (After Burgess) 161

76. Dytiscus Larvae 162

77. Pupa of Dytiscus 164

78. Larva of Limnobia replicata 167

79. Forked spine of Limnobia (enlarged) 168

80. Pupa case of Limnobia 169

81. Fore wing of Bee, showing marginal fold (×7) 170

82. Larva of Paraponyx stratiotata (enlarged) 173

83. Diagram of segment of Paraponyx, showing arrangement of tracheal gills 175

84. Gill of Paraponyx larva. (After De Geer) 176

85. Larva of Sialis (enlarged) 179

86. Diagram of Sialis larva, showing arrangement of gills 181

87. Pupa of Sialis 181

88. Larvae of Ptychoptera paludosa (from life) 184

89. Ptychoptera Larva (enlarged). Tail. (After Lyonnet) 186

90. Pupa of Ptychoptera. (After Lyonnet) 187

THROUGH A POCKET LENS