Beport of the State Geologist. 297 



PALEONTOLOGY. 

 Volume YIII. 



Since the completion of volume V, part I, on the Lamellibran- 

 chiata the Museum collections and material prepared for this 

 volume have been in the care and custody of Mr. C. E. Beecher, 

 whose services I expected would be given in the final revision 

 of the work. 



He has, however, found it necessary to give most of his time to 

 special Museum work and therefore little progress has been made 

 in the study of Brachiopoda. 



He had already, prior to 1886, prepared about 250 microscopic 

 slides for illustrating the shell structure of nearly eighty species 

 and about sixty photographic negatives have been taken. Unfor- 

 tunately for our progress in this work no field collections in this 

 direction have been made in many years, and the material now 

 available in the Museum collection is entirely insufiicient for any 

 satisfactory progress in the work and quite inadequate for the 

 purposes of the volume. 



The work in preparation for a revision of the Brachiopoda was 

 begun in 1867, after the completion of the fourth volume of the 

 Palaeontology and was continued with interruptions until 1878, 

 at which period twenty-eight plates had already been lithograped. 



In the original plan of this volume no especial limitation was 

 considered, but it was proposed to illustrate fully all the Palaeozoic 

 genera of Brachiopoda irrespective of geographical limitations. 

 The plates were to embrace illustrations of the external form, hinge 

 structure, the interior of the valve with its muscular and vas- 

 cular impressions together with the microscopic structure of the 

 shell. 



Since 1878, little progress has been made in the work, for this 

 volume, except in the preparation of sections for microscopic study, 

 little or almost no new material has been accumulated, and we 

 are not now as well prepared to go on as we were at that date. 

 Since the commencement of this work several important 

 monographs have been issued in England, France, Belgium, 

 Germany and Bohemia, the most important of these being 

 the monographs of Mr. Daiadson upon the Silurian, Devonian 

 and Carboniferous Brachiopoda. It follows without further argu- 

 ment or explanation that a work planned and partially executed 

 38 



