188 



die PseiuiomoMotisSchichtan uber den Kalken mit Tropites sub- 

 biillatus. Es ist diese Beobachtung umso wertvoller, als von 

 einigen Seiten die Richtigkeit der den Pseudomonotis-Schichien 

 auf Grund des palaontologischen Befundes zugewiesenen 

 Stellung in Zweifel gezogen worden war. 



Nach den neuen Untersuchungen des Prof. Perrin Smith 

 gliedert sich die Trias in Shasta County, CaHfornia, in 

 folgender Weise: 



Lias of Squaw Creek, without Cephalopods. 



Unconformitv 



Middle 

 Trias 



Pseudomonotis subcircularis slates, with only a few fossils 



Spiriferina beds, hard siliceous limestone, 50 ft. thick, with 

 few Ammonites. 



Juvavites beds, with /. of. subinterruplus and /. group of 

 Continni, many rotund Proarcesies sp. nov. and a few 

 Tropites, group of subbuUatus, about 200 ft. thick. 



Tropites beds with T. subbuUatus, T. torquillus, T. of. Mor- 

 loii, T. Sellai, T. Dittmari, Sagenites Herbichi, S. erina- 

 ceus, Eutomoceras Sandlingensis, Clionites many species 

 very abundant, Protrachyceras cf. Attila and many of 

 other species; Proarcestes several species. Nautilus tria- 

 dicus and many new species of Ammonites with some 

 new genera; Halobia superba etc. This bed in about 

 100 ft. thick. 



Halobia slates with Halobia superba in great abundance. 



Protrachyceras Homfrayi beds, with Halobia cf. rugosa and a 

 Ammonites. About 50 ft. of dark clay slates. 



About 1500 ft. of shales, with Ceratites, and Anolcites Whitneyi. 



Great thickness of conglomerates and eruptives amounting to 

 several thousand feet, no fossils. 



Upper Carboniferous limestones, with Fusulina cf. longissima etc 



