Mabch 17, 1911] 



SCIENCE 



435 



able. The depth of the fissure is unknown, 

 but the drop in the stream bed showed a 

 downward extent of six feet in which there 

 was no perceptible decrease in width. The 

 dike is parallel to the jointing in the porphyry 

 and can be traced for over fifty feet before it 

 pinches out. It is marked by a number of 

 pinches and swells, giving the formation the 

 appearance of several long, thin, connected 

 lenses of conglomerate standing vertically in 

 the porphyry. 



The obvious explanation is that a fissure in 

 the igneous rock has been filled by stream 

 wash, afterwards cemented by calcareous 

 waters, but the origin of the fissure is by no 

 means as clear. Many of the clastic dikes 

 hitherto described have been attributed to the 

 squeezing up from below of fragmental ma- 

 terial, while in those filled from above there 

 usually has been evidence of considerable 

 local disturbances to account for the forma- 

 tion of the open fissure.^ For reasons that 

 can not be given here, but which will be given 

 in a forthcoming paper on the district, it is 

 fairly well established that there has been at 

 Silverbell no recent rock movement sufficient 

 to form open cracks in any of the rocks. It 

 seems more probable that the dike in question 

 represents the result of a joint plane enlarged 

 by weathering, and fiUed in part by the prod- 

 ucts of this weathering and in part by sedi- 

 ment washed in by the stream. It is there- 

 fore a local feature, and bears no relation to 

 the dynamics of the district, although super- 

 ficially resembling clastic dykes that have been 

 the result of distinct erogenic movements. 



Charles A. Stewart 



COBNEIiL UNIVEBSITT, 



Ithaca, N. Y. 



'^note regarding maize flowers 

 It may be well to make here the preliminary 

 announcement of some results obtained in the 

 continuation of my studies of the evolution 

 of the " ear " of Indian corn (maize) begun 

 some years ago. It will be recalled that I 



'J. P. Newsom, Bull. Oeol. 8oo. Amer., Vol. 14, 

 pp. 227-268, and M. E. Campbell, Amer. Oeol., 

 Vol. 33, pp. 135-137. 



published in the Popular Science Monthly for 

 January, 1906, a paper entitled "What is an 

 Ear of Corn ? " in which I homologized the 

 " ear " with the central spike of the ordinary 

 "tassel," of staminate spikelets. Continuing 

 my studies I have now found perfect flowered 

 (hermaphrodite) spikelets in well-developed 

 " ears " occupying the usual lateral position 

 upon the plants. These are fully figured in a 

 paper which is nearly ready for publication 

 under the title of " Perfect Flowers in Maize." 

 It is found that these are produced upon 

 plants that differ markedly from the ordinary 

 type of Indian corn (maize). They are short- 

 jointed, with broad, leathery leaves, and I ven- 

 ture the suggestion that these plants may re- 

 semble in some degree the original form from 

 which our common maize was derived. One 

 of the photographs shows the remnants of an 

 abortive second flower in the pistillate spikelet 

 near the well-developed kernel taken from one 

 of these perfect-flowered ears, indicating that 

 these spikelets were once two-flowered. 



E. G. Montgomery 

 The Univebsitt op Nebbaska 



THE INDIANA ACADEMY OF SCIENCE 



The twenty-sixth annual meeting of the Indiana 

 Academy of Science was held in Indianapolis, 

 Friday, November 25, 1910. The president of the 

 academy, Professor P. N. Evans, chose as his sub- 

 ject for his annual address, " The Place of Re- 

 search in the Undergraduate Schools." Forty-two 

 regular papers were presented. Those of most 

 general interest were as follows: 



" Plants and Man — ^Weeds and Disease," Robert 

 Hessler, of Logansport. 



" Indiana Municipal Water Supplies," Charles 

 Brossman, Indianapolis. 



" Subterranean Drainage in the Bloomington 

 Quadrangle," J. W. Beede, of Bloomington. 



" Conservation Problems," Frederick J. Breeze, 

 of Lafayette. 



" The Properties and Reactions of Thrombin," 

 L. J. Rettger, of Terre Haute. 



" The Nature and Origin of the Fish Faima of 

 the Plateau of British Guiana," C. H. Eigenmann, 

 of Bloomington. 



" A Physiographic Survey of the Terre Haute 

 Area," Charles R. Dryer, of Terre Haute. 



" Paleolithic, Neolithic, Copper and Iron Ages 



