This Seventeenth Growth Symposium volume is comprised of papers presented in June of 1958. As stated in the foreword, the theme of the conference was that of "Differentiation and growth in response to a changing chemical environment." As Dr. Rudnick points out, and as is all too obvious, this permits an extremely wide range of papers. Subjects and authors are: (1) Wilde-Differentiation in respo...

T ‘‘social amoebae’’ of species Dictyostelium discoideum roam individually through the soil as long as their bacterial food is present. The social phase for these cellular slime molds begins when the food supply is exhausted. After some hours, the assemblage of amoebae aggregate into several large groups, each of which forms a worm-like slug that propels itself toward heat and light. This bring...

Embryology texts are most frequently organized in one of two ways depending on their intended purpose. Undergraduate texts are usually structured such that their sequence mimics the stages of embryolog-ical development. This, of course, makes sense, as it follows the method used by most instructors and allows one to rapidly locate information about a specific event of development. Unless, that ...

Szent-Gy6rgi. The nerve is described as an electro-chemical generator, although it is admitted that the events at the synapses are pirobably "not purely electrical." The theory envisages the electrotonic current as the "master tool of nervous integration." This may be true, but probably will not be proven for many years. In the meanwhile it is confusing to use the vocabulary of the electrical p...

The problem of adaptation is to explain the apparent design of organisms. Darwin solved this problem with the theory of natural selection. However, population geneticists, whose responsibility it is to formalize evolutionary theory, have long neglected the link between natural selection and organismal design. Here, I review the major historical developments in theory of organismal adaptation, c...