158 General Notes. [February, 



-formations are seen highly inclined, resting upon both the eastern 

 and western flanks. The railroad engineers have availed them- 

 selves of a line of drainage which cuts into the beds, forming a 

 long valley extending east and west. Its water shed is about ten 

 miles east of Fort Wingate,the streams on the one side flowing into 

 the Atlantic, and on the other side into the Pacific oceans. They 

 are called respectively the Puerco of the East and the Puerco of 

 the West. Puerco means muddy, and the rivers are well named. 

 The cliffs of jurrassic age on the north side of the valley are now a 

 thousand feet in height near Fort Wingate, showing the enormous 

 extent of the erosion. They consist everywhere of a soft red argilla- 

 ceous, arenaceous rock, and includea layer of gypsum. This material 

 is readily eroded by atmospheric agencies, and is carried down into 

 the valley during each rainy season in enormous quantities. The 

 lower levels for a distance of one hundred and fifty miles E. and W., 

 and from ten to twenty miles N. and S. consist of a vast deposit 

 of mud. Duringthe rainy season the streams are choked with it, 

 and after the cessation of the rains, the borders of dried sheets of 

 mud may be seen everywhere. Grass is buried up, but with many 

 plants, in time, struggles through it. On the northern side of this 

 valley, in the region of the extinct vent of San Mateo (Mt. Tavlor), 

 a lava sheet covers the older mud deposit. It displays exactly 

 the characteristics of the cooled lava of late eruptions of Mount 

 Vesuvius. It lies in innumerable ropes and coils, and forms like 

 heavy drapery, as though it had cooled but yesterday. In cooling 

 it has cracked into huge cakes. Water has percolated through 

 the fissures, and has, in some localities, removed a large part of 

 the supporting mud bed. Of course a portion of the mud is left 

 beneath the middle part of the block, forming a fulcrum. With 

 advancing erosion below, the lava block tips up, and stands ob- 

 liquely on its edge. Tracts of this kind form most forbidding 

 regions, and are absolutely impenetrable to any but small ani- 

 mals. Snakes appeared to be abundant in some localities passed 

 by the train.— E. D. Cope. 



Invertebrate Fossils from the Lake Valley district, New 

 MEXico.-Mr. S A. Miller, of Cincinnati, has identified the follow- 

 ing fossils from the silver-bearing carboniferous limestone of Lake 

 Valley, New Mexico: 



Strophomena rhomboidalis, Spin/era striata, S. novomchicana, 



n. sp., $ temeraria n. sp., Athyns lamellosa, A. planosulcata, Or- 



ta O. dalyana n. sp., u snmrcticu- 



'" .'/ ■ : '" .stulosa, R. tuta, n. sp., Plaivccras 



subca>s P ttosia„, Actin rinus dalyauns, n. sp. A \ L n %, A. 

 hneatm r, n. sp., Nautilus ( Euomfh , n * Ca- 



maraphoria occidental^ n. sp., T- / n " sp F 7 tw0 



undetermined species of Bryozoa of the family Fenestellidse ; 

 two. undetermined species of ZaphnttHs; a fragment of Ortho- 



