Report of the Director. 9 



The same processes have been adopted in some of the museums and laboratories 

 of our own country, and especially by Dr. J. J. Woodward, in the study of 

 the tissues of living forms, in the Museum attached to the War Department in 

 Washington. Much work of similar character has also been accomplished in 

 the Museum of Comparative Zoology at Cambridge, Mass. 



In our own case, it has already proved of invaluable service, and promises to 

 be still more important in future investigations. Up to the present time, sec- 

 tions have been made of rocks, minerals and fossils, numbering over 560, of 

 which more than 325 are polished, translucent cuttings of large size, and adapted 

 to microscopic study and photography. This work has been under the charge 

 of Dr. J. W. Hall, who has devised and arranged the machinery now in 

 use. Among this collection are a considerable number of specimens of Tenta- 

 culites, Stromatopora and European petrospongia which have been prepared by 

 Dr. Fritz-G-aertner. Each one of the sections has been carefully recorded, 

 noting the locality and geological formation. A catalogue of, these specimens 

 has been prepared, containing all the information possessed regarding the speci- 

 men at the time the work was done, indicating its geological position and the 

 place in the Museum of the specimen from which the sections have been cut, and 

 bearing a number corresponding to the section. 



In continuing this work, it is intended to prepare a series of cuttings of speci- 

 mens representing all the varieties of rock formations within the State of New 

 York, as well as of those fossil forms where such treatment will elucidate their 

 intimate and characteristic structure. 



In speaking of this subject, I should not omit an important feature in the 

 application of these preparations to educational uses. The translucent sections 

 attached to glass by Canada balsam, are not only susceptible of being pho- 

 tographed and printed from the glass plate, but these plates may be used in the 

 stereopticon or magic lantern, and the figures, projected upon a screen, magnified 

 to any desired degree ; thus affording the student an opportunity of learning, in 

 a general way, the structure of any class of objects which cannot be advantage- 

 ously studied from the exterior characters. 



Field Collections of Fossils and Minerals. 



The accumulating collections of rocks and fossils, resulting from the field- 

 work of the Museum, have been temporarily placed in a building especially 

 devoted to preparatory work upon the same. Here the fossils of the lower Hel- 

 derberg group, Oriskany sandstone, Upper Helderberg, Hamilton, Portage 

 and Chemung groups, were first separated and arranged, this work occupying 

 four or five months ; subsequently the Brachiopoda of the Hamilton and Che- 

 mung groups, and the Lamellibranchiata of the Hamilton group, have been 

 carefully separated, and notes made upon each species. In a book arranged for 

 that purpose, the record of every species is given, as to the number of specimens 

 from each locality, the condition of preservation, the character of the rock, its 

 manner of weathering and consistency, and also the associated species. The 

 arrangement of the Lamellibranchiata of the Hamilton group is nearly com- 

 pleted, but it will require several months longer to finish the fossils of the 

 order from the Chemung group. This work has been done by Mr. Lee 

 E. Brown. 



The object of this work is to give a comprehensive view of the comparative 

 abundance of each species, its geographical distribution and vertical range, and 

 the character of the sediment in which it lived. The notes mark the peculiari- 

 ties or characteristics of particular specimens or of the species itself. When 

 completed, this work will be especially important in showing the geographical 

 range of species ; and the results may be represented on any geographical or 

 geological map of the State. 



