ARRANGEMENT OF MUSEUMS. 203 



The geological divisiou of our museum should therefore contain 

 specimens of the rocks, under whicli term is included any portion 

 of the earth's crust, hard or soft, and of the fossils of our county. 

 The rocks should be arranged in one series, stratigraphically, and 

 the fossils, wliother plants or animals, in another, also stratigraphi- 

 cally. The rock-specimens will scarcely admit of classification, for 

 we can have but very few from each formation. The fossils may 

 be classified in each formation, and the classification adopted should 

 correspond, as nearly as possible, with that of our botanical and 

 zoological divisions. 



The geological formations which we now know to be present in 

 Hertfordshire, at the surface or below it, and which should be re- 

 presented in our museum by their rocks and fossils, are, in 

 ascending order, the Silurian, Devonian, Cretaceous, Eocene, and 

 Post-Pliocene or Pleistocene. The Silurian rocks are represented 

 by the Wenlock Shale in the New River Company's boring near 

 Ware, and the Devonian, or, more correctly, the Old Red Sand- 

 stone, was passed into at the boring at Turnford, near Cheshunt. 

 The Cretaceous rocks extend over almost the entire county, though 

 mostly covered by superficial deposits, and are represented by the 

 Gault, the Upper Greensand or Chloritic series, and the various 

 divisions of the Chalk formation. Of the Eocene rocks we have 

 the Woolwich and Reading beds and the lower portion of the 

 London Clay, forming the south-eastern margin of the county, and 

 having numerous outliers on the Chalk. And finally, gravels, 

 sands, and clays of Pleistocene age are spread superficially over the 

 greater part of the older deposits. In the drift-gravels, which form 

 such an important feature in the county, will be found specimens 

 of rocks and fossils of veiy different geological ages, drifted from 

 distant localities ; but these specimens should rightly be placed in 

 the Pleistocene division, which may, for instance, thus contain 

 specimens of Palfeozoic rocks from Charnwood Forest, Cumberland, 

 or Wales, and of fossils of Cretaceous and Liassic age. With these, 

 bones of still-existing Mammalia, and flint-implements and other 

 records of man, may be associated. The position of these rocks in, 

 and their relation to, the entire series of sedimentary strata, may 

 best be expressed in a table (Table I, p. 207) in which the members 

 present in Hertfordshire are indicated by distinctive type (italics). 



The whole of our geological collection, except perhaps any very 

 large specimens, should be exposed in flat or table cases, and maps, 

 sections, or other illustrations may be hung upon the walls. 



The botanical division of our museum will necessarily consist of 

 two artificially-distinct portions, for some vspecimens may be dis- 

 played in cases, while the majority, comprising dried specimens 



Sections, p. 127.) Dr. Giinther, on the other hand, maintains that to incor- 

 porate fossil with recent forms " would offer in its practical execution so many 

 and insuperable difficulties that we may well hesitate before we recommend the 

 experiment to be tried in so larfje a collection as the British Museum." (' Rep. 

 Brit. Assoc, for 1880,' p. 594.) Dr. Gray tried to unite the zoological and 

 palseontological collections in the British Museum, when under his charge, giving 

 up this attempt only after having convinced himself of its impracticability. 



