XI. 1 111-. HRAflllOl'ODA ANDOSTKACODAOF 'III I'. CI 1 AZV 

 Bv PicKcv I".. Raymond. 



(Pl.ATKS XXXill XXX\'I.) 



Brat-hiopods arc more nunieroiis in the Chazy than any other fossils, 

 but the number of species is relatively small. In this paper thirty 

 species are recognized. Only twelve of these are really common 

 and they rei>resent the genera Camarotcechia, Zygospira?, Leplccna, 

 Rafinesqnina, Plcctorthis, Ilebertella, Clitavihonites, and Camarella. 

 All but two of these belong to the Protremata. 



All four orders of the Brachiopoda are represented in the Chazy: 

 the Atremata by the Lingulidrc with four species; the Teleotremata 

 by the Rhynchonellidcc with five species and the Atrypida: with one; 

 the Xeotremata by two rare species; and the Protremata by the 

 Strophomenida with four species, the Orthidcc with ten species, the 

 Clitawbonitidcc with two species, and the Porambonitidcc with two. 



Of the thirty species, five are not found in the Champlain Valley, 

 though they are common in the ui)i)cr part of the Chazy at Montreal 

 and in the valley of the Ottawa. One other species is known only 

 from the type, so there are really only twenty-four species in the region 

 occupied 1)\' tlie t\i)ical Chazy. 



As a rule the brachiopods are well j:)reserved, but in spite of this 

 there are many details which remain obscure, and several problems 

 which can not be settled until material in just the right state of pres- 

 ervation is found. Thus, in spite of the abundance of Zygospira? 

 acniirostris, nothing has so far been learned of the interior, section- 

 cutting and grinding ha\ing yielded negative results. The generic 

 position of Orthidium? lamellosum is also exceedingly obscure. The 

 finest preservation is among those beautifully weathered-out fossils 

 collected by Professor Hudson from that wonderful little cleft in the 

 rocks at Sloop Bay, Valcour Island. This is the tyj^e-locality for 

 Hudson's species Clitambonites miilticostus and Schizambon duplici- 

 ttninitits. Pctroranid proua, Camaroiaxhia pristina, Leptcrna incrassata, 

 Ilebertella vulgaris, and Ca?iiarella varians are abundant there, while 

 a few other brachipods ha\-e been found, but are not common. 



The Orthidcc ha\e proved to be a most puzzling group, and the 



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