2 BULLETIN 64, UNITED STATES NATIONAL MUSEUM. 



Hall retained the manuscript and fossils for the remainder of his 

 life time, more than forty years, and after his death they were, at the 

 request of Secretary Langley, returned by the acting administrator 

 of his estate to the Smithsonian Institution. While the manuscript 

 was in Hall's possession he published four of Troost's genera, quoting 

 Troost's descriptions of three of them. He also published descrip- 

 tions of ten of the species the names of which had already been pub- 

 lished bj Troost [1850, pp. 60-62]. In each of these cases Hall used 

 as a type a specimen from another locality supposed to be identical 

 with the type of Troost. The descriptions, however, were written 

 by Professor Hall, Troost's description, then in his possession, being 

 quoted in one case only, that of Zeacrinus rnagnoliseformis. 



Prof. John M. Clarke [1905, pp. 256-257], writing with reference to 

 the matter, says: 



There was not in the entire immense collection which his [Hall's] death left among 

 his assets a single claim which had not been fully extinguished either by payment of 

 money or by transference of copies of his books which had cost him money. By the 

 latter method the Troost title was extinguished, and Hall had long before his death 

 acquired full right to use the materials as he saw fit. 



Earlier in the same paper he says: 



I am not acquainted with the proceedings by which this acquisition was finally 

 effected. Doubtless the transfer was gradually worked out and a full equivalent 

 rendered therefor. 



Meanwhile the matter of the Troost manuscript had apparently 

 been quite forgotten by the Smithsonian authorities, as shown by the 

 reply to Meek's inquiries regarding it. The letter, which has been 

 published [Schuchert, 1904, p. 220] is as follows: 



Washington, D. C, July 21, 1868. 

 My Dear Mr. Meek: I can tell you nothing about present condition of Troost's 

 paper or what Professor Hall has done or will do with it. Nor does Professor Henry 

 remember anything of any plan or arrangement. We have published nothing and 

 know of no publication.. 



Sincerely yours, S. F. Baird. 



F. B. Meek, Springfield, III. 



Interest in the manuscript was revived by Prof. Charles Schuchert, 

 formerly of the U. S. National Museum, and the present publication 

 is largely due to the earnest desire of Professor Schuchert and of lus 

 successor, Doctor Bassler, that justice should at last be done the 

 memory of this pioneer in the study of American Crinoidea. Troost 

 died believing that his monograph would soon be published, and it is 

 much to be regretted that it was not done while so mucL of the 

 material was new to science, and while the beautiful specimens he 

 loved could be associated with his name. 



In the following pages the manuscript of Doctor Troost, printed 

 in small type, is given nearly in full, for while parts of it are no longer 



