110 



Collecting from the Concretions. The calcareous and 

 pyrite concretions often yield good fossils. These may not 

 appear on breaking the concretion, because the splitting 

 seldom occurs in the right plane. Geikie suggests putting 

 the nodule into the fire and dropping it, when quite hot, 

 into cold water.* 



( 'ollecting from the Talus. This resolves itself into simply 

 picking over the loose material at the foot of the cliff and 

 selecting desirable specimens. Good material is often ob- 

 tained in this manner; but it is of little value for stratigraphic 

 purposes, as the various beds here have their fossils com- 

 mingled. Fossils from the talus should always be marked 

 as such. Not infrequently their position in the bank can be 

 ascertained, as in the case of the large cup-corals, which all 

 belong to the lower Moscow shale. I have frequently 

 found among the talus heaps, rock fragments which have no 

 local outcrops, but belong farther north, having been 

 brought down in the drift during the glacial period, as 

 noted in Chapter III.. Part I. This will serve to show how 

 unreliable talus specimens are, as distinct geologic hori- 

 zons raav easily be confounded. 



Wrapping and racking. Wrap each specimen separately 

 in newspaper, or, if very delicate, in tissue paper, and then in 

 newspaper. Small, delicate, free fossils should be placed be- 

 tween layers of cotton batting in boxes. When all the speci- 

 mens from one bed are wrapped, make a package of them by 

 wrapping them up in a piece of brown paper and securely 

 tying them with twine. With the specimens should be 

 packed a label, on which a record of the bed and locality is 

 made, and which bears a number corresponding to the entry 

 in the note-book. The legend on the label should also be 

 written upon the outside of the package, preferably with an 

 indelible pencil. Never neglect the labeling and recording in 

 the note-book, as otherwise much of the value of the collec- 

 tion may be lost. Also make the notes extensive and at the 

 time of collecting. An experienced collector will never trust 



* Text-book of ecology, 3d Ed., 1893, p. 673. 



