REPORT OF THE DIRECTOR I915 33. 



A collection of models and specimens illustrating the laws of 

 crystallization, occupying about 40 lineal feet of shelf space along 

 the south wall of the hall of minerals, has been added to the col- 

 lections of this division. This collection is accompanied by very 

 full explanatory labels and it has been planned in the hope that by 

 careful reading of the labels and study of the models and speci- 

 mens, the observer may acquire a reasonable conception of the 

 laws governing unit and derived forms of crystals. 



PALEONTOLOGY 



The Museum. In continuing the installation and labeling of the 

 collections in the hall of invertebrate paleontology, the synoptic 

 series of the stratigraphic exhibits was completed and provided 

 with large guide labels for each case, outcrop maps of the forma- 

 tions in the State, and charts showing the aspect of the American 

 continent at the time of the periods represented. These explana- 

 tory details give at a glance the most important data concerning 

 each formation. Wherever possible, rock specimens, illustrating 

 the varieties of rocks comprising the strata of each formation, have 

 been assembled at the sides of the cases. The addition of new and 

 better material is a constant process, and as such material is found 

 in the great reserve of the Museum, or is acquired in other ways, 

 it is incorporated into the exhibited collections so far as space will 

 permit. Thus the synoptic collection of the New York Paleozoic 

 fossils is constantly growing in quality and size. Into the ^'j wall 

 cases, which have been installed during the past year, the large 

 specimens of the stratigraphic collection have been placed. These 

 form an addition and supplement to the synoptic collections and 

 the wall cases are made to correspond as far as possible with those 

 of the general series alongside them. The large slabs placed on 

 pedestals along the walls have all been labeled. The special exhibits 

 of the Devonian sponges (six cases), of Devonian, fossils from the 

 Falkland islands, Argentina, Brazil, Turkey and Germany, most of 

 which have been the basis of reports and investigations carried on 

 in this office (4 cases), were finished. Of the starfishes and sea- 

 urchins, 2 cases are finished, while only i case of the crinoids has 

 been thus far installed. The wall cases of the special coral exhibit 

 (4 cases) are finished and the others are now in process of installa- 

 tion and labeling. The work of mounting and labeling the material 

 for the synoptic series has been done by Winifred Goldring, Edwin 



