. Contributions from the Botanical Laboratory, vol. 7. Botany; Botany. 200 Seifriz gametophyte of the cycad Ceratozamia (Fig. 19), down to the smallest space which gives to chromatin material its reticular appearance. Chamberlain makes the fundamental statement that the largest and smallest vacuoles are of the same morphological nature, i. e., the vacuoles of the chromatin (from anaphase to late prophase of the next mitosis) are of the same nature as those of the cytoplasm, only much smaller. He adds that any theory of heredity which is based on a linear arragement of genes will have to be aba
. Contributions from the Botanical Laboratory, vol. 7. Botany; Botany. 200 Seifriz gametophyte of the cycad Ceratozamia (Fig. 19), down to the smallest space which gives to chromatin material its reticular appearance. Chamberlain makes the fundamental statement that the largest and smallest vacuoles are of the same morphological nature, i. e., the vacuoles of the chromatin (from anaphase to late prophase of the next mitosis) are of the same nature as those of the cytoplasm, only much smaller. He adds that any theory of heredity which is based on a linear arragement of genes will have to be abandoned if it cannot be reconciled with a vacuolated struc- ture of the chromosomes. The geneti- cists have, unwittingly, now satisfied Chamberlain's request by converting the straight gene string into a spiral. It is evident that the possible ap- pearances which an emulsion may assume are varied. The distribution may be irregular (1, Fig. 20), orderly (B), under slight pressure (C), under full pressure (D), or such that the globules are in actual contact but not under pressure ('^;. Only slight distortion ot the last of these configurations is necessary to arrive at the picture given in Fig. 21 which is an exact copy, on a larger scale, of drawings of chromosome structure by Chamberlain (11). The figures illu- strate how chromomeres and a reticular structure of linin thread may result from the close packing of (irregular shaped) emulsion globules. It is possible to interpret some of the spiral structures seen in chromo- somes (21) on the basis of an emulsion. Sands (37) depicts a spiral arrangement of chromatin granules embedded in a linin matrix. Sands upholds the idea that chromatin and linin are distinct. The view-point taken in this article is the opposite, as illustrated by Fig. Fig. 19. Egg cell of Ceratozamia show- ing the highly vacuolate structure of the protoplasm. [From a publication by Dr. CHAMBERLAIN (11) and pubhshed with his kind permission.] The alveolar st
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