Association of American Geologists and Naturalists. 315 
homocercal forms of the fishes which are found as we ascend above the 
lias. He referred likewise to the Ornithoidichnite which he had found 
at Pompton, and submitted the same to the inspection of the Association, 
it being the first of these footmarks which had been discovered in the 
red sandstone of the Middle States of the Union; and noticed in con- 
nection with these tracks, the interesting discoveries of the bones of a 
gigantic struthoid bird, which formerly existed in New Zealand, the 
Dinornis of Prof. Owen, a good account of which was to be found in 
the Penny Cyclopedia for March, 1843, Vol. xxvr, p. 518.* 
In continuation Mr. R. then referred to the fossil rain-marks which 
are found in the same rocks, and submitted some remarkably well 
characterized specimens, from different parts of New Jersey and Mas- 
sachusetts. He showed that an objection which had been made at the 
last meeting to the genuineness of these rain-marks, founded on their 
appearance in relief on the upper surface of the rock, in some observed 
instances, could not be sustained; for the fact proved to be, that ina 
great number of cases in which soft unburnt bricks were exposed to 
rain, the secondary effect of the rain was to wash and denude the first 
markings in such manner as to leave only protuberances or markings 
apparently in relief. He found that the circumstances most favorable 
to the preservation of distinct pitted impressions of rain-drops and true 
casts of these in relief, were of somewhat rare occurrence. 
Prof. Rogers said that he believed it was the general opinion 
of our geologists that the new red sandstone of Connecticut and 
New Jersey belonged to the upper division of the formation of 
the same name in Europe. One fact which went far toward de- 
ciding this point was the occurrence of the Posodonomya keu- 
peri in the new red sandstone of Virginia, discovered by his 
brother, Prof. Wm. B. Rogers. 
The Secretary then read an interesting letter from Prof. Owen, 
on the Ornithichnites and Dinornis, [which is inserted in the 
present volume of this Journal, p. 185.] 
Prof. John Johnston of Middletown confirmed the statements 
of Mr. Redfield touching the numerous impressions of shrinkage 
marks, &c. observed in the new red sandstone at that place. 
Prof. Rogers remarked, that the cracks in the new red, were 
proofs of long continued dry weather, and their width might be 
proportionate to its continuance, while the size and depth of the 
rain-drops gave evidence of the strength of the shower ensuing. 
* See this Vol. p. 185. 
