R.WMdNi) : Bracmiopchia and Ostracoda of thk Cha/y. 257 



i8. Camarolivchia plena Hall. An internal cast showing the dental lamellae and 

 the undivided cast of the spondylium of the brachial valve. X 2. Specimen 

 from Valcour Island, now in Carnegie Museum. 



19-21. Camarotcechia orientalis (Billings). Three specimens from St. Martin 

 Junction, Quebec, Canada. Natural size. 



22. The same species. An internal cast from the Aylmer sandstone at Aylmer. 

 Quebec. Compare with 18 and 23. X 2. Carnegie Museum. 



23. Camarotcechia congregate (Conrad). An internal cast from the Hamilton 

 at Worcester, Otsego Co., New York. Compare with 18 and 22. X 2. Carnegie 

 Museum. 



24-31. Camarolccchia orientalis (Billings). \'arious views of four specimens from 

 St. Martin Junction. Natural size. 



32, 33. The same species. A specimen from the Mingan Islands. Collected 

 by W. H. Twenhofel and donated by Professor Schuchert. X 2. Carnegie 

 Museum. 



Pl.\te XXXIV. 



I, 2. Camarotcechia pristina Raymond. Photograph of two very small speci- 

 mens in Professor Hudson's collectioi». X about 4. 



3-6. The same species. Small specimens, X 2. 



7, 8. Internal casts of the same species. Compare 8 with 18, 22, and 23 of 

 the preceding plate. 



9, 10. Photographs of two more specimens in Professor Hudson's collection. 

 X about 2. 



11-14. Camarotcechia major Raymond. Three views of the holotype. 



14 is a photograph of the pedicle valve by Professor Hudson. 11-13. natural 

 size. Specimen in the Carnegie Museum. 



15-22. Zygospira? acutiroslris (Hall). Photographs and drawings of small 

 specimens in the Carnegie Museum. 19-22, X 4. 



23, 24. Schizamhon duplicimiiratus Hudson. A drawing of the brachial valve 

 and a photograph of the pedicle valve of a specimen in Professor Hudson's collection. 

 X 2. 



25. A small specimen from \'alcour which may be the same species as the last. 

 X2. Carnegie Museum. 



26-31. Petrocrania prona Raymond. Exterior and interior of several brachial 

 valves, showing the muscular and vascular scars. X 2. 29 and 30 are the same 

 specimen. 



32. Leptcena incrassata Hall. A large specimen from Sloop Island, showing 

 the alate cardinal extremities and the concentric wrinkles. X 2. Carnegie Mu- 

 seum. 



33-27. The same species. 33-35, interiors of brachial valves; 36, 37, pedicle 

 valves of small specimens, enlarged. 



PL.A.TE XXXV. 



1. Rajinesquina distans Raymond. Holotype. X 2. Carnegie Museum. 



2. Strophomena prisca Raymond. Interior of pedicle valve. Natural size. 

 Carnegie Museum. 



