[15] COLLECTING AND PREPARING FOSSILS SCHUCHERT. 



Such fossils are cleaned and hardened in tlie manner described on 

 page 24 as soon as practicable after they reach the laboratory. 



Limestone or ironstone nodules. — li^odules of limestone or ironstone 

 often have very fine fossils in the center. They should be broken and 

 examined, but sometimes it is not easy to split them so as to expose 

 the fossil. If the nodules promise well, a quantity of them should be 

 collected and treated in the laboratory "by putting the nodule into a 

 fire, and dropping it, when quite hot into cold water." ^ 



Importance of noting the exact location of fossils. — The second impor- 

 tant principle in collecting fossils is to determine accurately the geo- 

 graphical position of the locality and the horizon from which the fossils 

 have been taken. This information should be recorded while in the 

 field in a notebook. It is of great importance not only to the geologist, 

 but to the paleontologist as well. Fossils without locality have, as- a 

 rule, little value and generally are thrown away by careful students. 

 If a species is common and scattered over an entire hillside, it is well 

 to determine whether all the specimens are in place or derived from a 

 stratum near the top of the hill. The strata of a hill may represent a 

 very long period of deposition. 



At a locality where more than one fossiliferous zone occurs, never 

 collect promiscuously from all, but gather the fossils from one horizon 

 at a time. Pack each lot separately, with a field label. 



When collecting in loose rock or talus at the base of a clili', note this 

 fact on the field label, but when conditions are favorable never neglect 

 to ascertain the horizon or horizons from which this rock has fallen. 



If collections are made from many localities within a geologic basin 

 where certain common species constantly recur, do not fail to gather 

 these from all the places, since by such collections local faunal or floral 

 changes and geographic distribution are ascertained. 



"The theory that all the existing forms of life have been derived from 

 other forms by a natural j^rocess of descent with modification, and that 

 this same process has been in action during x)ast geological time, should 

 enable us to give a rational account not only of the peculiarities of 

 form and structure presented by animals and plants, but also of their 

 grouping together in certain areas, and their general distribution over 

 the earth's surface." ^ 



Fossils from the drift are sometimes very valuable, but when collect- 

 ing them the fact that they are from the drift should be noted. A drift 

 fossil may lead to the discovery of important outcrops, or give other 

 valuable information. 



PACKING INVERTEBRATES AND PLANTS FOR SHIPMENT. 



Wrap each specimen separately in paper, i^referably in old newspaper, 

 or, if delicate, in cotton or tissue paper. When the fossils are small 



iGeikie, Text-book of Geology, p. 673, 1803. 



2 Wallace, Darwinism an Exposition of the Theory of Natural Selection, p. 338, 

 1890. 



