![Carnegie Institution of Washington publication. OSBORNE AND MENDEL PLATE 1 B. A. Rat 238, female. Age 140 days, weight 144 grams, which is normal for a rat of same age as Carnegie Institution of Washington publication. OSBORNE AND MENDEL PLATE 1 B. A. Rat 238, female. Age 140 days, weight 144 grams, which is normal for a rat of same age as](https://c8.alamy.com/comp/RFT6BA/carnegie-institution-of-washington-publication-osborne-and-mendel-plate-1-b-a-rat-238-female-age-140-days-weight-144-grams-which-is-normal-for-a-rat-of-same-age-as-240-b-rat-240-female-age-140-days-weight-55-grams-same-brood-as-rat-238-c-rat-305-age-36-days-weight-55-grams-showing-the-appearance-of-a-normal-rat-of-same-size-as-240-a-and-b-show-the-contrast-between-two-rats-of-the-same-age-one-of-which-rat-240-has-been-stunted-the-lower-two-pictures-afford-a-comparison-between-two-rats-of-the-same-weight-but-widely-differing-in-age-the-older-stunted-rat-b-has-not-l-RFT6BA.jpg)
Carnegie Institution of Washington publication. OSBORNE AND MENDEL PLATE 1 B. A. Rat 238, female. Age 140 days, weight 144 grams, which is normal for a rat of same age as
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