CHAPTER IV.

Growth of Spiders.—Differences between Male and Female.— Differences between Old and Young.—Male and Female of Nephila and Argiope.—Heads of Male Erigone.—Palpal Organs.—Epigynum. —Use of Palpal Organs and Epigynum in Various Spiders.—Laying Eggs.—Cocoons of Drassus, Attus, and Epeira.—Cocoons of Argyrodes and Argiope.—Care of the Cocoon.—Parasites.—Growth in the Egg.—Hatching.—Habits of Young Spiders.—Moulting. —Habitats of Spiders.—Distribution of Spiders 86

LIST OF ILLUSTRATIONS.

PAGE 1. Under Side of Epeira Vulgaris 13 2. Foot of Epeira Vulgaris 14 3. Foot of Attus Mystaceus 15 4. Upper Side of Epeira Vulgaris 18 5. Section of Epeira Vulgaris 20 6. Mygale Hentzii 24 7. Dysdera Interrita and Eyes 26 8. Drassus 26 9. Agalena Nævia 27 10. Lycosa and Eyes 28 11. Salticus and Eyes 29 12. Thomisus and Eyes 30 13. Theridion 31 14. Mandibles of Epeira Vulgaris. Front View 33 15. Claw of Mandible 33 16. Spinnerets of Epeira Vulgaris 39 17. Single Spinning Tube 40 18. Spinning-Glands 40 19. Spinneret of Prosthesima 41 20. Spinneret of Agalena with some of the hairs removed 41 21. End of Thread 42 22. Trap-door Nests. Copied from Moggridge 47 23. Nest of Dolomedes 52 24. Web of Agalena 55 25. Web of Linyphia Marmorata 57 26. Web of Linyphia Communis 59 27. Pholcus swinging 61 28. Round Web of Epeira Vulgaris 62 29. Web of Zilla 65 30. Web of Nephila Plumipes. From Wilder 66 31. Part of Web of Nephila, to show the smooth threads. From Wilder 67 32. Epeira Spinea 69 33. Spinnerets of Amaurobius 72 34. Calamistrum of Amaurobius 73 35. Dictyna spinning Curled Web 73 36. Part of Web of Amaurobius 74 37. Part of Web of Dictyna, showing regular arrangement of threads 75 38. Unfinished Web of Triangle Spider. From Wilder 76 39. Finished Web of Triangle Spider, and Spider holding the Web. From Wilder 78 40. Young Lycosa flying 81 41. Flying Spider with a Thread attached to the Ground 84 42. Large Attus flying by a Brush of Threads 85 43. Male and Female Nephila Plumipes. From Wilder, in Proceedings Boston Society Natural History 78 44, 45. Heads of Males of Several Species of Erigone 88, 89 46. Palpal Organ of Mygale 89 47. Palpal Organ of Epeira 90 48. Palpal Organ of Theridion 91 49. Epigynum of Epeira Riparia 92 50. Epigynum of Theridion 93 51. Epigynum of Theridion 94 52. Copulation of Lycosa 95 53. Copulation of Linyphia 96 54. Copulation of Agalena 96 55. Copulation of Epeira Riparia 97 56. Drassus laying Eggs 99 57. Lycosa carrying Cocoon attached to her Spinnerets 100 58. Attus Mystaceus laying Eggs 101 59. Epeira Strix making Cocoon 101 60. Epeira Strix laying Eggs 102 61. Cocoon of Argyrodes hanging by a Stem 103 62. Cocoon of Epeira Riparia. From Wilder 103 63. Eggs during Segmentation 106 64. Eggs further Advanced 108 65. Young Epeira Riparia after First Moult 109 66. Moulting of Nephila Plumipes. From Wilder in Proceedings American Association 111 67. Nephila Plumipes just after Moulting. From Wilder 111

THE STRUCTURE AND HABITS OF SPIDERS.