Polarizing activity in the developing limb of the Syrian hamster.

The transplantation of small pieces of tissue from the limb buds of 9 1/2 -10 day hamster embryos to the wing bud of the chick results in the induction of supernumerary wing structures. The anteroposterior polarity of these induced structures is under the control of the transplanted hamster tissue. The developing hamster limb thus has limb polarizing activity similar to that found in avian species and, as in the chick, the activity is found primarily in the posterior region of the limb bud.     

Growth ofEscherichia coli B in a continuous culture under limitation by inorganic phosphate

During batch cultivation ofEscherichia coli in a medium deficient in inorganic phosphate, the growth curve after exhaustion of phosphate is linear. Results obtained in batch cultivation were used for deriving expressions for bacterial growth at a constant rate in a single-and multi-stage continuous system. It was found experimentally that the theoretical relations derived are satisfactory.