176 PALEONTOLOGY OF NEW YORK. 



■lender forms, without surface ornament, great difficulty will arise in indi- 

 cating Bpeoific distinctions among the Styliola. We may add that in Ten- 

 taculites (Sti/liolii) fisstinUu many of the specimens are expanded or bulbiform 

 at tlie apex, corresponding in this respect with the existing forms of Styliola. 

 This feature, however, is not observed in another form here described. 



Since this genus has not heretofore been noticed in America, I cite from M. 

 Bakrande (Systime Silurien, pp. 135, 13G) the condensed information given, as 

 below. 



•YKRTICAL AND HORIZONTAL DISTRIBUTION. 



"We have already shown in our table (p. 123) the vertical and horizontal 

 distribution of Styliola with that of Tentaculites, in pakvozoic countries. The 

 principal facts established for the first of these two genera are as follows: 



" 1. Styliola is thus far known only in certain countries of the old continent, 

 which appertain, some to the great southern zone, and others to the great central 

 zone. None have been found in the palaeozoic regions of America, nor in those 

 of the north of Europe. 



"2. No species of Styliola has hitherto been observed in the primordial 

 Silurian fauna, nor in the second fauna. As the second fauna presents about 

 seven distinct species of Tentaculites, spread through many countries, it follows 

 that the form which appears the most simple, among these two types, is precisely 

 that which has appeared the later during the palaeozoic times, at least accord- 

 ing to the actual state of our knowledge. 



"3. The total number of forms of Styliola, designated bynames, is nine. 

 The most ancient of these forms made their appearance during the existence 

 of the third Silurian fauna, and they have been designated by three specific 

 names. They are included in the geographical space occupied by Bohemia, 

 Thuringia and the Harz. 



"4. The remaining six described forms belong to the Devonian period, and 

 to the countries on the borders of the Rhine, the Harz, Thuringia and Saxony. ( 



"We may remark the inequality of their vertical extent. A single form 

 (Sti/l. lacigala, Roembb) is found in the schists of Wissenbach, that is to say, in 

 the inferior subdivision of the Devonian system, according to the classification 

 of Sir Rod. MoBCHJSOH (Sih/ria, p. 419. 1859). Its presence is also indicated 

 by Prof. F. A. EUnCBB in the Stringocephales limestone of the Harz, that is to 

 Bay, in the middle subdivision. The five other species all belong to the 

 superior subdivision of the same system, for they have been found only in the 

 Cypridinia schists, and in the formation called Kraiiieii/clstein which makes 

 part of the same subdivision. 



" The following table indicates the vertical range : 



