June 6, 19()2.] 



SCIENCE. 



905 



the South produce running vines when trans- 

 planted to the North change to a bushy habit. 



Mr. 0. P. Hartley outlined some results 

 obtained in growing corn from red-eared 

 sports. In one case a pure red ear was found 

 in a field of a white race which had been bred 

 true to type for a number of years. Seed from 

 this red ear was planted, and in the first gener- 

 ation about 45 per cent, of the progeny had 

 red ears while the remaining 65 per cent, gave 

 white ears. Some of the red ears were self- 

 fertilized, and in the second generation grown 

 from such self- fertilized seed 83 per cent, of 

 red ears were produced. Another sport was 

 described where in a race of pure bred white 

 corn an ear was produced which was mainly 

 red, but had a white spot at the base on which 

 the kernels were white with very fine red 

 stripes. The red grains from this ear when 

 planted produced progeny in which 50 per 

 cent, of the ears were red, while the kernels 

 from the white spot gave progeny in which 

 50 per cent, of the ears had seed like that 

 planted, with fine red stripes, and 50 per cent, 

 had pure white ears. 



Mr. H. J. Webber exhibited a plant of trail- 

 ing arbutus (Epigcea repens), received from 

 South Carolina, which produced double flow- 

 ers. The doubling was caused by the stamena 

 developing into petals, the expanded filaments 

 being united into a tube similar to the corolla 

 in which it was inserted. Mr. Webber also 

 called attention to an experiment with cotton, 

 showing the prepotency of pollen of diiferent 

 species. In the summer of 1900 flowers of Sea 

 Island cotton were opened about 7 a.m. and 

 abundantly pollenated with their own pollen, 

 after which they were bagged. These same 

 flowers were opened again about 11 a.m. — four 

 hours l^er — and dusted abundantly with 

 pollen of upland cotton. The seeds produced 

 by such cross-pollenated flowers were planted 

 the next year and gave over 50 per cent, of true 

 hybrids, showing that pollen of upland cotton 

 on Sea Island is sufficiently prepotent over 

 the plant's own pollen to give a large per- 

 centage of hybrids even when applied four 

 hours later. It was pointed out that results 



similar to these were obtained by Darwin in 

 experiments with different varieties of cabbage. 

 Herbert J. Webber, 

 Corresponding Secretary. 



GEOLOGICAL SOCIETY OF WASHINGTON. 



At the 131st meeting, held May 14, 1902, 

 the following papers were presented by mem- 

 bers of the Maryland Geological Survey: 

 'The Potomac Group in Maryland,' by W. 

 B. Clark and A. Bibbins. 



The Potomac group is composed of four dis- 

 tinct formations called from below upward 

 the Patuxent, the Arundel, the Patapsco 

 and the Earitan formations. These are sep- 

 arated by clearly defined unconformities. The 

 two lower formations are provisionally as- 

 signed to the Jurassic because of the dis- 

 covery by Professor Marsh of dinosaurian 

 remains within the Arundel formation, the 

 dicotyledonous plant remains being mainly 

 confined to the Patapsco and Raritan forma- 

 tions. Only a few dicotyledons are knovm 

 from the lower formations. By the grad- 

 ual transgression of the formations north- 

 ward the Earitan ultimately rests upon the 

 Piedmont Plateau of New Jersey, while south- 

 ward the transgression of the Tertiary grad- 

 ually buries the higher formations, the Eari- 

 tan disappearing near the latitude of Wash- 

 ington. 



The character of the Potomac basin of 

 deposition is shown by well borings which indi- 

 cate a distinct rise in the level of the Potomac 

 surface in the Delaware peninsula. 



'The Correlation of the Coal Measures in 

 Maryland,' by W. B. Clark and G. C. Martin. 



The Maryland Coal Measures have hitherto 

 been largely studied independently of the 

 same deposits in adjacent regions in Pennsyl- 

 vania and in West Virginia, and as a result 

 an independent classification has gradually 

 been developed. The authors find, however, 

 that not only the stratigraphic sequence but 

 the fossiliferous horizons are identical with 

 those in the adjacent regions of Pennsylvania 

 and West Virginia, and they consider that 

 the same classification should obtain. In the 

 case of the lower members of the Coal Meas- 



