426 Miscellaneous. 



Species unica : 



Amphichana Kinder manni, Ph. 

 Hab. litus Oceani Pacific! ad oppidum Mexicanum Mazatlan. 

 I obtained this remarkable shell from M. Kindermann in Valpa- 

 raiso. — Wiegmann's Archiv, Part I. 1847. 



INFUSORIAL DEPOSIT AT DOLGELLY, NORTH WAliES. 



To the Editors of the Annals of Natural History. 



Lancaster, JMay 12, 1847. 



Gentlemen, — It may interest some of your readers to learn that 

 an infusorial earth has been found near Dolgelly in North Wales. 



This substance appears to have attracted the notice of some gen- 

 tlemen engaged in the Geological Survey, who transmitted it to 

 London for chemical analysis. A small portion came into my hands, 

 and the microscope showed that it consisted almost exclusively of 

 siliceous infusoria more or less perfect*. I am informed that this 

 earth can be procured, in considerable quantity if desirable, on ap- 

 plication either to Mr. James Price, Goat, or to Mr. James Jones, 

 Saddler, Dolgelly. I am. Gentlemen, yours very truly, 



Christopher Johnson. 



A Sketch of the Geology of Texas. By Dr. Ferdinand Rcemer. 



During the four months which I have already passed in Texas, 

 my time has been employed in the study of its geological relations : 

 and although my knowledge of the country is yet incomplete and 

 mostly confined to the western section of the territory, I may hope 

 that the following sketch of what I have seen, considering the little 

 that is known, will prove of interest to your readers, and afford a 

 basis for further investigations. 



It is not a very encouraging fact to the geologist in Texas, that 

 only there, where civilization ceases and the wilderness commences, 

 the geological relations of the country begin to be interesting. The 

 line which separates the settled part of the country from the hunting 

 grounds of the Indians, is almost exactly identical with that which 

 divides the more modern diluvial and alluvial deposits from the se- 

 condary formations. The three points, lying in the same straight line, 

 San Antonio di Bexar, New Braunfels, (the German settlement on 

 the Guadaloupe,) and Austin, are alike the extreme frontier parts of 

 Western Texas, and the limit of the cretaceous deposits of the upper 

 country towards the south-east. In the few observations which I have 

 to make, I shall therefore separate the particulars relating to the 

 lower country from those bearing upon the secondary formations in 

 the section of country lying beyond the just-mentioned line. 



The route by which I reached the north-western section of the 

 country, leading through Houston, San Felipe, Austin, Columbus 



* From an examination of a sample kindly forwarded by our correspond- 

 ent, we can most fully confirm his statement. It abounds in forms of Ba- 

 cillaria, Navicula, Gaillonella, &c. ; and contains some remarkably beau- 

 tiful and peculiar annular forms. — W. F. 



