■522 Geological Society. 



though in that favoured region the return of wheat is never under 

 seventy, and sometimes as much as a hundred-fold. The return, on 

 an average, in Great Britain, is not more than nine for one." 



Mr. Half's paper on the Diatomacece, No. 3, was then read, con- 

 taining descriptions of the genera Striatella Tessella and Tetra cyclas. 



" On the Development of Leaves ;" by Dr. Dickie, Lecturer on 

 Botany, King's College, Aberdeen. The author concluded by stating, 

 " that it cannot be said that the forms of leaves in flowering plants 

 have any dependence whatever on their venation, since young leaves 

 are lobed, &c. previous to the appearance of the veins. The truth 

 appears to be, that the quantity of cellular tissue in a leaf determines 

 the development and positions of the veins, and not the opposite." 



GEOLOGICAL. SOCIETY. 



June 29, 1842. — A paper " On the Fossil Foot-prints of Birds and 

 Impressions of Rain-drops in the Valley of the Connecticut." By 

 Charles Lyell, Esq., V.P.G.S. 



The deposit in which these impressions, long known on account 

 of the researches of Prof. Hitchcock, occur, is situated in a trough of 

 hypogene rocks, about five miles broad, the strata, which consist of 

 sandstone, shale and conglomerate, dipping uniformly to the east at 

 angles that vary from 5° to 30°. Mr. Lyell first examined the red 

 sandstone at Rocky Hill, three miles south of Hartford, in Connec- 

 ticut, where it is associated with red shale and capped by twenty 

 feet of greenstone. Many of the beds are rippled, and cracks in the 

 shale are filled by the materials of the superincumbent sandy layer, 

 showing, the author observes, a drying and shrinking of the mud 

 while the accumulation of the strata was in progress. The next 

 quarries he examined were at Newark in New Jersey, about ten 

 miles nest from New York city. The excavations are extensive, 

 and the strata dip, as is usual in New Jersey, to the north-west, or 

 in an opposite direction to the inclination in the valley of Con- 

 necticut, a ridge of hypogene rocks intervening. The angle is about 

 35° near Newark. The beds exhibited ripple-marks and casts of 

 cracks, also impressions of rain-drops on the upper surface of the fine 

 red shales. Mr. Lyell states, that he felt some hesitation respecting 

 the impressions first assigned to the action of rain by Mr. Cunning- 

 ham of Liverpool, but he is now convinced of the justness of the 

 inference, having observed similar markings produced on very soft 

 mud by rain at Brooklyn in Long Island (New York). On the 

 same mud were the foot-prints of fowls, some of which had been made 

 before the rain and some after it. 



Mr. Lyell next visited the red and green shales of Cabotville, north 

 of Springfield in Massachusetts, where some of the best Ornithich- 

 nites have been procured, chiefly in tlie green shale. The dip of the 

 beds is 20° to the east, a higlier inclination, the author says, than 

 could have belonged to a sea-beach. He observed in the same quar- 

 ries ripple-marks as well as casts of cracks, and he was informed 

 that the impressions of rain. drops have likewise been found. 



In company with Prof. Hitchcock, Mr. Lyell afterwards examined 

 a natural section near Smith's Ferry, on the right bank of the Con- 



