File:Heredity and sex (1913) (14578204129).jpg

Identifier: hereditysex00morg (find matches)
Title: Heredity and sex
Year: 1913 (1910s)
Authors: Morgan, Thomas Hunt, 1866-1945
Subjects: Heredity Sex
Publisher: New York, N.Y. : Columbia University Press
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library

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sperm ducts. (After Kopec.) young caterpillars and found no change in the color, orsize, of the male. He also removed the ovaries fromyoung caterpillars, and again found no effect in the fe-male. The same experiments were later carried out ona large scale by Meisenheimer, who obtained similarresults. Meisenheimer went further, however, and per-formed another operation of great interest. He removedthe male glands from a male and implanted in their THE EFFECTS OF CASTRATION 149 place the ovary of a female, while it was still in a veryimmature condition. The caterpillar underwent itsusual growth, changed to a chrysalid, and then to amoth. The moth showed the characters of the male.The presence of the ovary had produced no effect what-ever on the body character of the individual. Whenthis individual was dissected, Meisenheimer found thatthe ovary had completely developed. It containedmature eggs, and the ovary had often established con-nection with the outlets of the male organs that had
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Fig. 75. — Testes of Lymantria (Porthetria) dispar transplanted to female.They have connected with the oviducts. (After Kopec.) been left behind, as seen in Fig. 74, taken from Kopecsdescription. The converse experiment was also made. The ovarieswere removed from young caterpillars, and in theirplace were implanted the male sex glands from a youngmale caterpillar. Again no effects were produced on themoth, which showed the characteristic female size andcolor. On dissection the testes were also found to havegrown to full size and to have produced spermatozoa(Fig. 75). These remarkable results, confirmed by Kopec, show 150 HEREDITY AND SEX that in these insects the essential organs of reproduc-tion have no influence on the secondary sexual char-acters of the individual. They show furthermore thatthe male generative organs will develop as well inthe female ^s in the body of the male itself, and viceversa. It is evident, then, in insects (there is a similar, butless complete., series of

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