BUFFALO SOCIETY OF NATURAL SCIENCES III 



A comparison of this analysis with that of the Bertie shows that 

 the two types of deposits are as different as could weU be imagined, 

 che deep sea mud having combined alumina and silica 77.75 per cent, 

 as opposed to 28.98 per cent, while the combined CaO and MgO is 

 5.00 per cent as compared to 63.10 per cent in the waterlime. One 

 cannot argue much, however, from this pronounced difference between 

 the two types, because it must be borne in mind that in the late 

 Siluric the greater portion of exposed land areas in northern and 

 western North America was covered with limestones or dolomites 

 and that in consequence the muds which accumulated far out to 

 sea, and which were the finest particles derived by the erosion of 

 those land surfaces, would of necessity have been high in calcium and 

 magnesium, whereas the blue muds accumulating in our present oceans 

 are derived from a great diversity of rocks in which the limestones 

 form a very small part. Thus, while we can find no analogous mud 

 deposit in modern oceans, we are not justified in saying that such a 

 one might not have formed in the past under different conditions; 

 and I can, therefore, see no characteristics in the chemical composi- 

 tion of the rock to preclude the possibility of its deposition at a con- 

 siderable distance from land. We are not, however, lacking in an- 

 other criterion when the physical characteristics fail to be restrictive; 

 the type of fauna represented is the safest guide in the interpretation 

 of ancient regions of deposition. There is no region where muds are 

 accumulating in the sea today, whether near shore or farther from 

 land, where an abundance of organic remains is not being included. 

 Along the entire Atlantic coast of North America the muddy facies 

 of the littoral zone swarms with life, and while many of the species 

 are confined to that facies it certainly cannot be claimed that where 

 muds are accumulating there is a paucity of plant and animal life. 

 Detailed studies of restricted areas of the ocean floor have proved that 

 a large and varied fauna flourishes even where muds pour in in great 

 quantities from the land. Thus, Walther (295, 36) has found that 

 the muds in the Bay of Naples contain a fauna of about n 20 species 

 of invertebrates and fishes. The fauna of the Bertie contains not 

 two dozen species and nearly all of these belong to one phylum and 

 to one class in that phylum, namely, the merostomes. Such, a fauna 

 cannot be considered as marine in any sense, if we accept the prin- 

 ciples for the criteria of fossil faunas, based upon the study of recent 

 faunas (p. 67 above). It is characteristic of no portion of the sea- 

 shore, bays, lagoons, or estuaries, nor of the open sea, whether in 



