40 Forty- FOURTH Report on the State Museum. 



discussion of the generic relations of the older forms among the 

 Articulate Brachiopods, and in tracing the lineal descent of certain 

 generic features from their earliest appearance in the Cambrian 

 period. 



In this connection I should also make my acknowledgments to 

 Mr. Geo. F. Matthew of St. John for the loan of specimens, both 

 of the inarticulate and articulate forms of Brachiopoda, repre- 

 sented in the genera Acrothele, Acrotreta, Lingulella, Linnars- 

 SONIA, KuTORGiNA, and Orthis-Protorthis, all from the Cambrian of 

 New Brunswick. Also for his valuable notes and suggestions 

 regarding some of the genera which will be fully acknowledged in 

 the text of the volume. 



After returning from Montreal and Ottawa I visited many of the 

 public and private collections of Indiana, Illinois, Missouri and 

 Kansas and obtained the loan of material which has been very 

 useful in completing the illustrations and discussion of generic 

 forms of the Carboniferous period. 



I have been heretofore, in 1888, and am now again, indebted to 

 the Trustees of the Illinois State Museum, through Dr. Lindahl, 

 the Curator of the Museum for the loan, in the first instance, of 

 their very fine collection of Spiriferoids. During the past sum- 

 mer Dr. Lindahl, at my request, has sent down to the State Hall, 

 for use in the preparation and completion of volume YIII, the 

 entire typical collection of Orthis, the streptorhynchoid forms 

 under several genera, the Chonetes and Productus from the 

 Illinois State Museum. These have been of essential service in 

 the progress of the work. 



The University of Missouri granted me the privilege of select- 

 ing from their collections, for study and comparison, a series of 

 specimens illustrating certain species described by Prof. Swallow 

 while State Geologist of Missouri. These specimens have been 

 of essential service in comparing species and of correcting errone- 

 ous views regarding certain genera and species current in the 

 catalogues. 



From the beginning of the work the Trustees of the American 

 Museum of Natural History have granted the privilege of using 

 such material in the collections of that institution as might be 

 needed in the progress of this work on the Brachiopoda. This 

 privilege has been of great advantage, since these collectioiife con- 

 tain the types and typical specimens of many of the genera of the 



