110 JULES MARCOU ON THE TACONIC OF GEORGIA 



shales found in the Hudson Kiver valley, with the "Utica and Lorraine" which actually 

 contain the fauna of Sandy Creek, with its Acephalae (Laniellibranchiae) and its charac- 

 tei's of the upper part of the second fauna (Cambrian) containing forms already fore- 

 shadowing the advent of the third fauna (Sihu-ian). 



Such a survey would diminish, considerably, what is still called in eastern New York 

 the Lorraine shales (Hudson River group), and reduce them to smaller dimensions in 

 thickness as well as in area. The old " black shales group " of Dr. Emmons will have 

 then to be considered and carefully surveyed from Poughkeepsie to Bald Mountain 

 (Washington County), then through Yermont to Phillipsburgh and Quebec city; that 

 is to say, all the western part of the great band of the Taconic system, so well deline- 

 ated on the supposed lost map of Emmons, which Avas pi-epared by him to accomjiany 

 the first volume of the "Agriculture of ISTew York." 



A few words about that map will not be out of place here. 



The suppressed Emmons' agricultural and geological map. — The geological map of the 

 state of ^ew York, described at pages 361 and 3G2 of the "Agriculture of New York, 

 Natural History of New York, Part v, Volume i," Albany, 1846, referred to in "Mapo- 

 teca Geologica Americana," p. 59, Washington, 1881 {Bulletin U. S. Geol. Surv., No. 

 7), "as stolen or destroyed bj^ persons unknown, so that it was never issued with the 

 proper volume" (see letter of Emmons to Jules Marcou, Dec. 28, 1860, jiublished in 

 "The Taconic system and its position in stratigraphic geology," Proc. Amer. Acad., xii, 

 188, Cambridge, 1885), has lately and unexpectedly made its appearance at the State Li- 

 brary and at the New York State Museum of Natural History at Albany. 



About ten years ago, and consequently about fourteen years aftei- the death of Dr. 

 Emmons, the state librarian, on the plea that the first issue of the map of 1812 was out 

 of print, began to distribute it as the "Geological map of the state of New York," the 

 first two words of the title being omitted. But this year sevei-al copies have been dis- 

 tributed without abbreviation. The full title is, "Agricultural and geological map of 

 the state of New York, by Legislative authority, 1811:." The abbreviation made on some 

 of the copies distributed during the last ten years consists in the cutting off of the words 

 ^'■Agricultural and,'''' forming a first line added to the map of 1812. The table of colors 

 and classification of rocks is the same, with the exception that the Taconic system, which 

 does not appear in the tabular view with his name or any sort of notice, exists on the 

 map in drab color, as a large band extending from the Canada boundary line to New 

 Jersey and the Tappan sea on the Hudson Kiver. 



The map being hand-colored, some vai'iation in the coloi'ing must be expected. In the 

 copy I have now under my feyes, the Calciferous and Black River and Birdseye limestones 

 are confounded in a single color, pale blue; while, in the map of 1812, the colors are very 

 distinct, the Calciferous being brown and the Trenton (Black River and Birdseye) sky- 

 blue. Another difference exists, for the three colors of the Utica, Hudson River and 

 Oneida, which wei'e very distinct in the map of 1842, are mingled together, more or less, 

 under a single gray-lilac color. Finally the Portage and Chemung groups, colored green- 

 gray in 1842, are very pale yellow in the map of 1844. 



The appearance of the long lost mai) of Dr. Emmons, I am glad to say, has been ac- 

 companied by the return to the state Museum of Natural History at Albany of " the 

 rocks illustrating the Taconic system, all taken out by order" many years ago (letter 



