26 



REPORT ON THE PAL^ONTOLOGICAL COLLECTIONS. 



By Alpheus Hyatt. 



The work on the collection of Trilobites, which consists in get- 

 ting together all the species of each genus, and the selection of 

 appropriate specimens for exhibition in the Stratigraphical Collec- 

 tions, was continued during the first part of the year. This pro- 

 cess not only eliminates materials suitable for exhibition from the 

 mass of the collections, but also greatly improves the accessibility 

 and arrangement of the latter, and considerably diminishes the 

 space occupied by them in the rooms where they are stored. The 

 greater part of the Assistants' time has, however, been given 

 to a revision of the magnificent collection of Fossil Cephalopods 

 for the express purpose of selecting representative forms of the 

 genera for exhibition in the Systematic Collection. 



The Senary Collection furnished the larger number of the 

 Palaeozoic types, and the whole of this has been roughly revised 

 and brought into one room together with all the other collec- 

 tions of Fossil Cephalopoda, and the specimens arranged in their 

 appropriate generic groups. Quite a number of genera were 

 more or less closely revised in order to bring them up to the lat- 

 est published investigations, and representatives of the new groups 

 into which they have been divided were picked out, but most of 

 this work was necessarily of a preliminary nature, not including 

 any close revision of species, and much still remains to be done 

 before this class of fossils can be reported as finished. The mag- 

 nitude of some parts of this collection is certainly astonishing, 

 the specimens of the Senary Collection representing the Ortho- 

 ceratidse, although stored with strict attention to economy of 

 space, now occupy one hundred and ninety-four traj^s, and num- 

 ber about eleven thousand specimens, and approximately about 

 eighty species. 



During the progress of the dusting of this and other collections, 



