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Show Delicate Surgery on Tiny Fruit-Flies Aids Biolosdsts D Glass Needles and Microscopes Used PASADENA, CALIF. Surgical Sur-gical operations of incredible incred-ible delicacy are used for the transplantation of eyes, sex glands, legs, wings, and other organs of tiny insects the size of ordinary gnats, by two young scientists, Drs. Boris Ephrussi and G. W. Beadle. Doctor Ephrussi is a Frenchman, French-man, Doctor Beadle an American. Ameri-can. The work was begun in Paris, at the Institute of Physico-Chemical Biology, and has been continued at the William G. Kerckhoff Laboratories Labora-tories of the Biological Sciences at the California Institute of Technology. Techno-logy. The insects operated on are the favorite experimental animals of geneticists, the handy little fruit-flies fruit-flies known more learnedly as Dro-sophila. Dro-sophila. They are subjected to the transplanting technique while still infants, in the larval or grub stage. Only Sixth of Inch Long. Although even the largest of these larvae are only a sixth of an inch long and a twenty-fifth of an inch in diameter, both scientists work at the same specimen at the same time. The operating table is a small glass laboratory dish, and the two biologists work with hollow glass needles, drawn out to hair-line fineness. fine-ness. Each man watches through a double - barreled microscope. With the needles they pluck up the rudimentary rudi-mentary "buds" of organs which have been dissected out of one larva, and inject them into the body of another. The "host" larvae, with their added transplanted organs, are then placed in an incubator and kept at a temperature of 77 degrees Fah-.renheit Fah-.renheit for four or five days, during which time they transform themselves them-selves first into pupae and then emerge as full-grown fruit-flies. Transplanted Organs Grow. Some of the transplanted organs, of course, are never of any use to the insect that has acquired them. An eye grafted into the abdomen of a fruit-fly becomes a perfect eye, but because it lacks the proper nerve connections does not help its unconscious possessor to see. On the other hand, transplanted .ovaries often successfully make connection con-nection with a female insect's egg-laying egg-laying apparatus, and these then function quite as well as the owner's original pair. These experiments have a purpose pur-pose decidedly more serious than just showing that so difficult a biological bi-ological stunt can be carried through successfully. Drosophila has been the most important organism or-ganism for demonstration of the basic principles of heredity ever since Dr. Thomas Hunt Morgan, now director of the biological laboratories lab-oratories at the California Institute of Technology, carried out the pioneer pio-neer researches in this particular field many years ago. But certain tissue transplantation work, of value val-ue in studying these principles, has hitherto been possible only with larger larg-er but less understood animals, like insects, fishes and frogs. |