Insects, cause or carry disease, 40; numbers, 40; annual loss caused by, 41; how they carry disease germs, 55. Irrigating ditches, 104. Itch-mite, 36. Jackson, Dr. D.D., 67. Jennings, 22. Jiggers, 38, 53. Jigger-flea, 53. Kala-azar, 173. Kerosene, 104. Koch, 44. Læmopsylla cheopus, 153. Lamprey-eel, 2. Lancisi, J.M., 107. Larvæ, of flies, 64; of mosquitoes, 78. Laveran, A., 108. Laverania, 109. Lazear, Dr. Jessie W., 123. Leeuwenhoek, Anton von, 22. Lepra bacillus, 36. Leprosy, 36, 70, 171. Lice, 54. Linnæus, 76. Little house-fly, 49. Lock-jaw, 18. Low, Dr. A., 118. Lucilia spp., 48. Lugger, Prof. Otto, 38. Malaria, early theories in regard to, 106; parasite that causes, 108; life history of parasite, 109; parasite in mosquito, 113; summary, 117; experiments, 118. Maggots, 63. Malta or Mediterranean fever, 171. Mange, 37. Manure-fly, 59. Manson, Sir Patrick, 112, 123. Mastigophora, 20. Melanin, 110. Micrococcus melitensis, 171. Microbes, 10. Mites, 26, 35. Mosquito, 76; abdomen, 86; adults, 81; Anopheles, 91; how they bite, 84; effect of bite, 87; blood, 90; how they breathe, 89; classification, 91; and dengue, 169; eggs, 77; and elephantiasis, 164; enemies, 77; fighting, adults, 101; larvæ, 103; larvæ, 78; and malaria, 106; malarial parasite in, 113; mouth-parts, 83; other species, 96; pupæ, 80; salivary glands, 87; thorax, 85; and yellow fever, 94, 120. Mouth-parts, of fly, 60; of mosquito, 83. Mus, norvegicus, 154; rattus, 154. Nanga, 45. Nematodes, 164. New Orleans, yellow fever in, 120, 132. Noctiluca, 21. No-see-ums, 46. Ochromyia anthropophaga, 49. Oil of citronella, 102. Oil of pennyroyal, 102. Oriental sore, 174. Ornithodorus moubata, 34. Oscinidæ, 52. Otospermophilus beecheyi, 155. Oxwarbles, 50. Panama Canal zone, 135. Paramoecium, 22. Parasite, defined, 1; classes of, 4; in new regions, 5; diseases caused by, 7; effect on host, 9; relation to host, 14. Parasitism, 3. Pasteur, L., 44. Pearls, 13. Piroplasma bigeminum, 29. Plague, early history of, 142; fleas that transmit, 153; and flies, 70; and ground squirrels, 155; how combatted in San Francisco, 143; results of other investigations, 150; Verjbitski's experiments, 147; work of Indian Plague Commission, 146. Plasmodium, 109. Protozoa, 19; classes of, 20. Proboscis, of fly, 60; of mosquito, 80. Privies, 72. Privy-fly, 59. Pseudopodia, 20. Psoroptes communis, 37. Pulex irritans, 154. Punkies, 46. Pupæ, of house-flies, 64; of mosquitoes, 80. Pyrethrum, 102. Rats, and plague, 143, 145; species of, 154. Red-bugs, 38.