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The Anatomy of the Honey Bee

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The Anatomy of the Honey Bee This is a reproduction of a library book that was digitized by Google as part of an ongoing effort to preserve the information in books and make it universally accessible. https://books.google.com APR 29 1227 Technical Series, No. 18. U. S. DEPARTMENT OF AGRlCULTURE, BUBKAU OF ENTOMOLOGY. L. 0. HOWARD, Entomologist and Chief of Bureau. THE ANATOMY OF THE HONEY BEE. BY R. E. SNODGRASS, Agent and Expert. Issued May 28, 1910. WASHINGTON: GOVERNMENT PRINTING OFFICE. 1910. Technical Series, No. 18. U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF ENTOMOLOGY. L. 0. HOWARD, Entomologist and Chief of Bureau. THE ANATOMY OF THE HONEY BEE. BY R. E. SNODGRASS, Agent and Expert. Issued May 28, 1910. WASHINGTON: GOVERNMENT PRINTING OFFICE. 1910. BUREAU OF ENTOMOLOGY. L. O. Howard, Entomologist and Chief of Bureau. C. L. Mablatt, Assistant Entomologist and Acting Chief in Absence of Chief. R. S. Clifton, Executive Assistant. W. F. Tastet, Chief Clerk. F. H. Chittenden, in charge of truck crop and stored product insect investigations. A. D. Hopkins, in charge of forest insect investigations. W. D. Hunter, in charge of southern field crop insect investigations. F. M. Webster, in charge of cereal and forage insect investigations. A. L. Quaintance, in charge of deciduous fruit insect investigations. E. F. Phillips, in charge of bee culture. D. M. Rogers, in charge of preventing spread of moths, field work. Rolla P. Cubrie, in charge of editorial work. Mabel Colcord, librarian. Investigations in Pee Culture. E. F. Phillips, in charge. G. F. White, J. A. Nelson, B. N. Gates, P. E. Snodgrass, A. II. McCray, agents and experts. Ellen Dashiell, preparator. Jessie E. Marks, clerk. T. B. Symons, collaborator for Maryland. H. A. Surface, collaborator for Pennsylvania. J. C. C. Price, collaborator for Virginia. 2 LETTER OF TRANSMITTAL. U. S. Department of Agriculture, Bureau of Entomology, Washington, P. C, October 19, 1909. Sir: I have the honor to transmit herewith a manuscript entitled " The Anatomy of the Honey Bee," by Mr. R. E. Snodgrass, agent and expert, of this Bureau. It embodies the results of detailed studies made by Mr. Snodgrass and should prove of value as bring ing to the bee keeper reliable information concerning an insect of such great economic importance, and also as furnishing a sound basis in devising new and improved practical manipulations. I recommend its publication as Technical Series, No. 18, of the Bureau of Entomology. Respectfully, L. O. Howard, Entomologist and Chief of Bureau. Hon. James Wilson, Secretary of Agriculture. 3 CONTENTS. I. Introduction II. General external structure of insects 10 III. The head of the bee and its appendages 26 1. The structure of the head 26 2. The antennie and their sense organs 32 3. The mandibles and their glands 39 4 . The proboscis 43 5. The epipharynx IV. The thorax and its appendages 53 1. The structure of the thorax 53 2. The wings and their articulation 59 3. The legs 66 V. The abdomen, wax glands, and sting 69 VI. The alimentary canal and its glands 84 1. The general physiology of digestion, assimilation, and excretion. 84 2. The salivary glands 87 3. The alimentary canal 90 VII. The circulatory system 107 VIII. The respiratory system IX. The fat body and the (enocytes 119 X. The nervous system and the eyes "* XI. The reproductive system 1. The male organs 132 2. The female organs. 134 Explanation of the symbols and letters used on the illustrations 139 Bibliography 148 Index 151 5 ILLUSTRATIONS. Page. Fia. 1. Median longitudinal section of body of worker 8 2. Diagram of generalized insect embryo 12 3. Example of generalized insect mouth parts 17 4. Diagram of generalized thoracic segment 18 5. Typical insect leg -1 6. Diagram of generalized insect wing and its articulation 22 7. Diagram of terminal abdominal segments of a female insect and early stage in development of gonapophyses 25 8. Example of a swordlike ovipositor 25 9. nead of worker bee - 27 10. Heads of worker, queen, and drone 29 11. Median longitudinal sections of heads of worker and drone 30 12. Antennal hairs and sense organs 36 13. Mandibles of worker and drone 40 14. Internal mandibular gland of worker 42 15. Mouth parts of worker 43 16. Median section through distal half of mentum and has;' of ligula of worker 50 17. Epipharynx and labrum of worker 51 18. Sense organs of epipharynx 52 19. Median longitudinal section of head of worker 52 20. Dorsal view of ventral walls of body of worker 53 21. Thorax of worker 54 22. Lateral view of mcsotergum of worker 50 23. Thoracic terga of worker 57 24. Upper part of left mesopleurum of worker 58 25. Wings of llymenoptera 60 26. Basal elements of wings of Hymenoptera 61 27. Median section through thorax of drone 6 1 28. Internal view of right pleurum of mesothorax of drone 65 29. Legs of worker, queen, and drone 67 30. Claws and empodium of foot of worker 68 31. Tarsal claws of worker, queen, and drone 32. Lateral view of abdomen of worker 70 33. Ventral view of abdomen of worker 70 34. Dorsal view of abdominal sterna of drone 70 35. Sixth abdominal sternum of worker, queen, and drone 72 36. Semidiagrammatic view of left side of sting of worker 75 37. Ventral view of sting of worker 76 38. Section of small piece of wall of poison sac 79 39. Sections of alkaline gland of sting 79 40. Details of sting of worker 81 41. Tip of abdomen of worker with left side removed 82 6 ILLUSTRATIONS. 7 Page. Fio. 42. Alimentary canal of worker 85 43. Details of pharyngeal and salivary glands 88 44. Honey stomach of worker, queen, and drone 94 45. Longitudinal section of honey Btomach and proventriculus of queen . 97 46. Histological details of alimentary canal of worker 103 47. Dorsal diaphragm of drone, from one segment 108 48. Small part of dorsal diaphragm of drone 110 49. Pericardial chamber of one segment in worker Ill 50. Tracheal system of worker 113 51. Tracheal system of worker 117 52. Nervous system of worker 123 53. Brain and suboesophageal ganglion of worker 125 54. Horizontal section of compound eye and optic lobe of worker 127 55. Histological details of compound eye of worker 128 56. Reproductive organs of drone 133 57. Reproductive organ and sting of queen 135 THE ANATOMY OF THE HONEY BEE. L INTRODUCTION. The anatomy of the honey bee has been for years a subject of much interest to those engaged in bee keeping both for pleasure and for profit. This interest is due not only to a laudable curiosity to know more of the bee, but to the necessity of such information in order to understand fully what takes place in the colony. All practical manipulations of bees must depend on an understanding of the be havior and physiology of bees under normal and abnormal circum stances, and those bee keepers who have advanced bee keeping most by devising better manipulations are those, in general, who know most of bee activity. In turn, a knowledge of bee activity must rest largely on a knowledge of the structure of the adult bee. Studies on the anatomy of the bee have not been lacking, for many good workers have taken up this subject for investigation. The popular demand for such information, however, has induced untrained men to write on the subject, and most accounts of bee anatomy contain numerous errors. This is probably to a greater extent true of the anatomy of the bee than of that of any other insect. Frequently the illustrations used by men not trained in anatomical work are more artistic than those usually found in papers on insect anatomy, and they consequently bear the superficial marks of careful work, but too often it is found that the details are in accurate. It has therefore seemed the right time for a new presenta tion of this subject based on careful work. The drawings given in the present paper are original, with the exception of figures 12, 54, and 55, and have been prepared with a thorough realization of the need of more accurate illustrations of the organs of the bee, especially of the internal organs. Mistakes will possibly be found, but the reader may be assured that all the parts drawn were seen. Most of the dissections, moreover, were verified by Dr. E. F. Phillips and Dr. J. A. Nelson, of this Bureau, before the drawings were made from them. An explanation of the abbreviations and lettering is given on pages 139-147. It is hoped that the work will furnish the interested bee keeper with better information on the anatomy of the bee than has hereto fore been offered to him, that it may provide a foundation for more detailed work in anatomy and histology, and, finally, that it will be 9 10 THE ANATOMY OF THE HONEY BEE. of service to future students of the embryology and physiology of the bee. With this last object in view the writer has tried to sum up under each heading the little that is at present known of insect physiology in order to bring out more clearly what needs to be done in this subject. II. GENERAL EXTERNAL STRUCTURE OF INSECTS. When we think of an animal, whether a bee, fish, or dog, we uncon sciously assume that it possesses organs which perform the same vital functions that we are acquainted with in ourselves. We know, for example, that an insect eats and that it dies when starved; we realize therefore that it eats to maintain life, and we assume that this involves the possession of organs of digestion.
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