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a field excursion enjoyed jointly by the Torrey Botanical Club, 

 and the New York Chapter of the Appalachian Mountain Club, 

 and also by members of the New York Microscopical Society 

 and the New York Bird and Tree Club, on Sunday-, May 19. 

 The route was from Riverdale, N. J., on the Greenwood Lake 

 division of the Erie Railroad, to Pompton Lake, up Firey Brook 

 to Pine Lake, a new artificial water body, and along the basalt 

 ridge which connects Packanack and Preakness Mountains. It 

 was intended to go to Franklin Notch, but a heavy thunderstorm 

 which drenched everyone, drove the party out early to Upper 

 Preakness, to take bus to Paterson and New York. Sixteen were 

 present, ten women and six men. 



The first of these plants in unusual conditions to be examined 

 was the Walking Fern, in the only occurrence of the plant in 

 northeastern New Jersey, on the walls of the gorge of Firey 

 Brook, about a quarter of a mile east of Pompton Lake, and 

 about 200 yards below the dam impounding Pine Lake. This 

 is a very interesting gorge. Its upper walls show normal Trias- 

 sic Newark sandstone, mostly in massive strata, with some thin- 

 bedded shaly streaks. At the bottom, a few feet above the brook, 

 is exposed a peculiar conglomerate, with a matrix of Newark 

 sandstone, inclosing pebbles, up to the size of an apple, of three 

 kinds of rock, Newark sandstone, basalt of the same age, and 

 limestone of probable Silurian age. The limestone is attributed 

 to beds of such material, laid down in marine waters east of the 

 Archean granites and gneisses of the Ramapo mountains, 

 which dropped thousands of feet in the disturbance which 

 included the famous Logan Line fault, at the end of the Triassic 

 period, or early in the Cretaceous. The beds dropped out of 

 present sight, but the conglomerate including pebbles worn 

 from them, by atmospheric weathering and assembled in some 

 sea beach or erosion fan, was apparently unafifected by the dis- 

 turbance, except that it presents the same inclination shown 

 in all of the Triassic sandstones, toward the west, in the direc- 

 tion of the great fault line bordering the old rocks. 



The presence of these limestone pebbles, which make up 

 not more than twenty per cent, probably less, of the content 

 of the conglomerate, evidently provided the calcium usually 

 preferred by the Walking Fern. That there is scarcely enough 

 lime in the rock for the Fern to be happy is indicated by its 



