GENERAL CHARACTER AND CORRELATION 707 



eaves, 35 include eleven species, among which are Spiriferina borealis 

 Whiteaves and Daivsonites canadense Whiteaves, which have been doubt- 

 fully identified from Hamilton Bay. Mojsisovics 36 has pointed out that 

 some of these fossils are indicative of Karnic age. Three of the Liard 

 Eiver species (Daivsonites canadense, Nathorstites McConnelli, and Na- 

 thorstites lenticularis) , one of which occurs at Hamilton Bay, have been 

 found, according to Bohm, 37 in the Upper Triassic rocks of Bear Island 

 between Norway and Spitsbergen. The Triassic rocks of Bear Island are 

 generally regarded as of Karnic (possibly Lower Karnic) age, and an 

 assignment of the beds on Liard Eiver to the same position has been made 

 by Freeh 38 on the basis of the presence of the above mentioned species, 

 which are common to the two regions. 



The Hamilton Bay fauna may also be tentatively correlated with that 

 from Bear Island and referred to the Karnic. This fauna possibly repre- 

 sents a boreal facies of the Karnic which has not been recognized farther 

 south in North America. 



Zone of Halobia cf. superba.- — The Chitistone limestone, which is the 

 basal formation of the Upper Triassic section in Chitina Valley, is repre- 

 sented in other parts of the Pacific Mountain system by limestones which, 

 although thinner, are similar to the Chitistone limestone in their general 

 lithologic character, in their stratigraphic position between underlying 

 volcanic rocks and overlying shales or cherts with Pseudomonotis, and in 

 the general character of their fauna. The limestones which should be 

 correlated with the Chitistone limestone include those of the upper Su- 

 sitna Valley, of Herring Bay on Admiralty Island, and part of the Tri- 

 assic limestone of Hamilton Bay on Kupreanof Island. 



The fauna of these limestones includes unidentified species of Tro- 

 pites, Juvavites (?), and Arcestes, a species of Halobia closely related to 

 Halobia superba Mojsisovics, and many other fossils of lesser significance. 

 These fossils show that the fauna is certainly Upper Triassic, and that it 

 probably belongs in the middle or Karnic stage of the Upper Triassic. 

 Although most of the identified genera of brachiopods and pelecypods 

 have a long range, yet both the character of many of the individual forms 

 and the general aspect of the assemblage are unmistakably Triassic. The 



85 J. F. Whiteaves : On some fossils from the Triassic rocks of British Columbia. Con- 

 tributions to Canadian paleontology, vol. 1, pt. ii, No. 3, 18S9, pp. 127-149, pis. 17, 18. 



38 Edmund von Mojsisovics : Beitrage zur Kenntniss der obertriadischen Cephalopoden- 

 Faunen des Himalaya. Denkschriften der kaiserlichen Akademie der Wissenschaften. 

 Wien, Bd. lxiii, 1896, p. 697. 



87 Johannes Bohm : Ueber die obertriadische Fauna der Bareninsel. Kungllga Svenska 

 Vetenskaps-Akademiens Handlingar. Bandet 37, No. 3, 1903, pp. 56-58, 61-64, 73-76. 



38 Fritz Freeh: Die zirkumpaciflsche Trias. Lethfea geognostica, Tell il, Das Meso- 

 zoicum, Band 1, Trias, 1908, pp. 488-491, 508. 



