PRELIMINARY OBSERVATIONS. 13 
beautiful Silurian Brachiopoda that abound in the rocks of that extensive country than 
Prof. Jamus Hau, State-Geologist ; and to his magnificent work, ‘ Palzeontology of New 
York,’ for 1847-52, the reader is particularly directed. The same eminent paleontologist 
has also devoted many pages of the ‘ Annual Reports of the Regents of the State of New 
York Library, &c.’ for 1857-65 to the description and illustration of a vast number of 
new Paleozoic genera and species of Brachiopoda; and to these, as well as his ‘ Report 
on the Fourth Geol. District, New York,’ 1843, we shall often have occasion to refer. 
Conrap, in the ‘Journal of the Acad. of Nat. Sciences of Philadelphia,’ vol. vin, 
1842 and 1843, and in the ‘ Annual Geol. Reports, New York,’ 1838-40, has de- 
scribed a great many species of Silurian Brachiopoda. 
The reader will also find a number of American Silurian Brachiopoda described and 
figured in the followimg works ; but a more complete list will be given hereafter : 
Emmons, ‘ Report, Second Geol. District, New York,’ 1842-3 and 1859. 
Vanouxem, ‘Report, Third Geol. District, New York,’ 1842-43. 
F. pe Castennav, ‘ Essai sur le Terrain Silurien de l’Amerique du Nord,’ 1843. 
Eaton, ‘ Geological Text-Book, 1831. In this work the author has identified some 
European species, and proposed names for other Brachiopoda. 
Martuer, ‘ Report on the First Geol. District, New York,’ 1843. 
example, amongst the Terebratulze they have observed more than sixty species which required to be located 
in several new genera, such as Gonotrema, Diclisma, Pleurinia, Stropheria, Strophomena, Clipsilia, &c., 
besides the true genera Productus and Terebratula, &c. It is, however, probable that some of these 
American Silurian genera and species had been described somewhere by Rafinesque prior to 1820; but 
where and when we do not know. I would, therefore, feel obliged to any person who might be able to 
afford me correct information upon the matter. Can any of them have been published in Rafinesque’s 
‘Travels and Discoveries in the West,’ Pittsburg, 1818, and announced in ‘ Silliman’s Journal’ for 1818, 
vol. i, p. 311, as well as in the ‘Giorn. Encycl. Sicil.,’ or in the same author’s ‘Atlantic Journal’? 
These books arerare, and I have not been able to obtain access to them. In 1825 Blainville, to 
whom Rafinesque’s former works must have been known, both describes and figures the American genus 
Strophomena ; but the oldest diagnosis written by Rafinesque himself with which we are acquainted dates 
1831, and may be found in his ‘ Continuation of a Monograph of the Bivalve Shells of the Ohio River, and 
other rivers of the Western States,’ which was published separately at Philadelphia, in October, 1831, and 
subsequently in Chenu’s ‘Biblioth. Conchyl.’ Other genera, which can hardly be made out, will be found 
recorded in p. 381 of the ‘Bull. Soc. Géol. de Fr.’ for 1839, as well as in the ‘ Journal de Physique’ for 
1839, vol. Ixxxviii, p. 427; and most likely also in C.S. Rafinesque’s ‘ Enumeration and Account of some 
Remarkable Natural Objects in the Cabinet of Philadelphia,’ 1831. None of the American paleontologists 
with whom I have communicated upon the subject appear to be able to afford us any more definite infor- 
mation upon the subject ; it is, however, probable that the first notice of American Silurian Brachiopoda 
will be found to date back not later than 1819 or 1820. 
