Permo-C arhoniferous Ammonoids of the Glass Mountains 20Q 



old world. We find a very intimate relative of Perrinites in the Sici- 

 lian Hyattoceras, which may very well have been derived from the 

 Texan form. Another genus which may have developed from Per- 

 rinites is Waagenoceras, which is found in Sicily, together with Hyat- 

 toceras and in Texas in a horizon overlying the zone of Perrinites. It 

 cannot yet be decided if Perrinites persists still in the zo'ne of Waagen- 

 oceras, although I have seen some ammonoids from the Delaware beds 

 of the Guadalupe Mountains which look suspiciously like Perrinites: 

 unfortunately T have not had an opportunity to study the suture. 



In India we do not find either Perrinites nor Waagenoceras, but a 

 much higher developed form of the Cyclolobinae, the type of the genus 

 Cyclolohns, and quite a number of species nearly related to it. 



Karpinsky was surprised by the non-existence of any Cyclolobinae 

 in the cephalopod-bearing sandstone of the Artinsk of the Ural, as 

 well as of Darwas in Bokhara, Central Asia. This led him to suppose 

 that the Artinsk sandstone might be a little older than the Sosio lime- 

 stone. But he justly remarks that those Cyclolobinae may simply 

 not have developed in the Ural and may belong to a more southern 

 province. Now we see that in the strata in Texas which most probably 

 represent the cephalopod-bearing sandstone of the Artinsk, Cyclolo- 

 binae exist in great ntmibers; in fact, are the most frequent fossils. 

 But these types are not known in other parts of the world. 



I think it would be somewhat dangerous to suppose that the Cyclolo- 

 binae prove the existence of a southern province with a different fauna 

 from that of the more northern regions. This might lead us to the 

 supposition of climatic belts or provinces, for which I do not see suffi- 

 cient reason at the present time, taking into account our limited know- 

 ledge of the marine fauna of the Permo-carboniferous and the Per- 

 mian. We must always keep in mind that the faunas so rich in species 

 and genera described from these formations occur in very few local- 

 ities which are separated by extremely long distances. For the time 

 being, I think it would be much more prudent to suppose that the 

 Cyclolobinae originated in America, that they then migrated in part 

 to southern Europe, and still later to the waters of the Australasian 

 Ocean. 



San Antonio, Texas, DR. EMIL BOSE. 



August, 19 1 8. 



