National Geographic : 1944 Feb
Life Story of the Mosquito BY GRAHAM FAIRCHILD * ONE of my earliest experiences with mosquitoes occurred when as a young ster I was returning from Barro Colo rado Island in the Canal Zone. On leaving, I noticed a small boil on my leg, which grew progressively more painful. I finally went to the ship's doctor to have it treated. After applying a compress, he extracted from the wound a disgusting white grub nearly half an inch long. On arriving in Washington, I told my entomologist friends of my experience. They were much annoyed with me for not allowing the grub to finish its career in my leg! It was the larva of the human botfly (Dermatobia hominis), an insect then rare in collections. The adult female, which looks much like an overgrown bluebottle fly, hovers about ani mals and people in the woods. It does not bite, but comes only to seek mosquitoes and other small flies. These the botfly catches carefully in flight, without injuring them, and glues its slender eggs to the sides and bottoms of their abdomens (Color Plate VIII). It even seems able to gauge the "pay load" each can carry. On small mosquitoes it will deposit only a few eggs, but to large flies it will attach fifty or more. When a mosquito bearing these eggs lights on a man or an animal, the body warmth causes the young larvae to crawl out and drop to the skin. They soon burrow in and in a few months grow to maturity, crawl out, drop on the ground, and pupate. Years later when I went to Brazil to study mosquitoes, I became only too well acquainted with this nuisance. It is a serious pest to Brazilian cattle, rendering some hides worth less and seriously detracting from the value of others. Each grub leaves a hole in the skin. We often saw cattle with backs and shoulders one mass of lumps from the grubs. Wild animals are also attacked. We ob tained a number of grubs from the tail of an ocelot. Of course, the biggest nuisance was to our selves. I remember extracting eight young grubs from my ankle on one occasion, and later found others in my scalp and back (page 190). Of all the winged pests, mosquitoes are the most widely distributed. There is scarcely a spot on the globe where mosquitoes do not take their toll of blood and sleepless hours. People who come from places notorious for mosquitoes are sometimes proud of the size and viciousness of their native product. Many times I have listened to spirited debates on the relative nuisance value of Alaska and New Jersey mosquitoes. To prove the superiority of the Louisiana breed, a New Orleans friend told of being awakened one hot night by the voices of two large mosquitoes, discussing whether they should eat him immediately or carry him away. The first proposal won, for, as its proponent said, "If we try to carry him off, one of the big fellows will take him away from us." People have immortalized these nuisances by naming places after them. There is a Mosquito Mountain in Maine and several states have Mosquito Creeks. One mosquito looks pretty much like an other to most people. Indeed, even those who have made a life study of them are not always able to agree on just what a particular speci men may be. Mosquito Portraits Done from Life The accompanying color series of mosqui toes, painted exclusively for the NATIONAL GEOGRAPHIC MAGAZINE, graphically depicts some of the more interesting and important members of the vast mosquito family. Ex treme accuracy of detail characterizes each painting. Even the hairs on legs and antennae of each mosquito are accurately drawn. To paint such exact reproductions required months of first-hand observations. Small breeding pools were set up in the studio, so that the entire life cycle of mosquitoes could be carefully observed. As the painting progressed, Dr. Alan Stone, entomologist of the Bureau of Entomology and Plant Quarantine, Department of Agri culture, carefully checked each detail to assure precision. Mosquitoes belong to the most primitive division of flies, a division which includes the crane flies; the sand flies; the black flies, or buffalo gnats of the north woods; the punkies, or "no-see -ums"; and several other groups. Mosquitoes may be distinguished from their relatives by their slender bodies, long legs, and long, biting beaks. These are flexible tubes containing slender lancelike organs attached at the base to a powerful suction pump. Their bodies and wings are clothed with scales (Plate IV and page 191). * Formerly a medical entomologist with the Gorgas Memorial Laboratory in Panama, Dr. Graham Fair child is now a First Lieutenant in the Sanitary Corps, Army of the United States, working on new insect repellents and insecticides.