210 J. F. Whiteaves— Recent Dredging operations 
have an adequate explanation of the apparent absence of organic 
remains from many under-clays, not only of lignites, but also of 
Paleozoic coal beds. That the leaching process which deprived 
the coal beds of all the ash ingredients necessary to vegetation, 
has also been instrumental in the removal of iron and organic 
matter from the Carboniferous fire-clays, has been often sug- 
gested; but the efficacy of the process, when combined with 
pressure, to obliterate all traces of the softer parts of plants and 
animals, imbedded in clays, has hardly been sufficiently dwelt 
upon. That another phase of the same agencies has been instru- 
mental in obliterating the teeming fauna of the Port Hudson 
beds, whose character can now be studied only in a few limited 
localities, I have already shown.* And there can be little 
doubt that the absolute dearth of organic remains which has 
thus far frustrated all my attempts to gain a definite clue to the 
age of the “Grand Gulf” beds of the Gulf border, is largely due 
to the same cause, and not to the conversion of the Mexican 
Gulf into a “Dead Sea” during the Post-Eocene Tertiary period. 
Lignite beds composed of drifted materials are not rare 1n 
the Gulf border, from the lowest Cretaceous beds to those of 
the Champlain era. But they are usually very much localized, 
and consist mainly of driftwood, which is not only over- and 
underlaid by sandy materials, but also intermixed with them. 
Beds of compact lignite underlaid to any great extent by sand, 
are quite exceptional. 
Arr. XXV.—On recent Deep-Sea Dredging operations in the 
Gulf of St. Lawrence; by J. F. WHITEAVES. 
seventy successful hauls of the dredge. The cruises were 
essentially four in number, but on the whole the first yielded 
the greatest number of novelties. 
* Smithsonian Contr. Knowl., No. 248, p. 12. 
