4 INTRODUCTION. 



sacrificed. Some of his friends, therefore, felt impelled to collect and arrange, 

 as completely as they were able, what had been done, and, if possible, to obtain 

 from subscribers a sufficient sum to defray the expense of publication at least, 

 and perhaps also to benefit his family. With the cooperation of the Smith- 

 sonian Institution, which generously granted the use of the drawings, besides 

 subscribing for a large number of copies, the object has been accomplished, and 

 the work is before us. We believe that these copies, rivalling as they do the 

 actual specimens, will be really useful to those pursuing similar scientific investi- 

 gations; they will at least furnish a beautiful table-book, to excite an interest 

 in the community in the marvels of nature. 



The sketch of his life which follows is an abstract of a Discourse delivered by 

 Dr. Henry I. Bowditch to the Franklin District Medical Society. The compilation 

 of the text, the determination of the species and the additional remarks upon 

 them, and the references to the original specimens, is the work of Thomas T. 

 Bouve, Esq., who particularly desires to have here expressed his indebtedness to 

 Prof. Hitchcock and to Roswell Field, Esq., for their aid in enabling him to 

 identify many of the stones from which the drawings and photographs were 

 taken, and for other assistance. 



AUGUSTUS A. GOULD. 



Boston, January, 1861. 



