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J 33 Sdeiitijic Intelligence, 



3. Microscopic examination of Soundings^ made "by the U. S, Coast 

 Survey off the Alhmtic Coast of the United States; by Prof. J. W. 

 Bailey, (16 pp. 4to. with a plate; from vol. ii, of ihe Smithsonian 

 Coatributions to Knowledge.) — After special details with referenee to 

 the character of the material in each case of sounding, Prof. Bailey 

 gives the following very important statements as the general results of 

 the examinations. 



1st. The most remarkable fact determined by the examination of 

 the above mentioned soundings is, that in all the deep soundings, from 

 that of fifty-one fathoms S. E. of Montauk Point, to that of ninety fath- 

 oms S. E. of Cape Henlopen, there is a truly wonderful development 

 of minute organic forms, consisting chiefly of Polythalamia, which occur 

 in an abundance rivalling those vast accumulations of analogous forms 

 constituting the maris under the city of Charleston, S. C. 



2d. While there is a general resemblance between the species found 

 in all the deep soundings above mentioned, the same species of Poly- 

 thalamia occurring with few exceptions at each locality, yet each place 

 has its predominant species ; thus in the most southerly soundings, (H, 

 No, 1, 90 fathoms,) there occurs a much greater number of Globigeri- 

 na than in any of the others; while Textilaria atlantica, although pres- 

 ent, is by no means so abundant as in " G, No. 8, 89 fathoms. 



3d. Infusoria, as well as Polythalamia, occur in the deep soundings; 

 but the infusoria are few in number, and consist of Coscinodisci, Galli- 

 onella sulcata, and other species, which probably swim freely in the 

 ocean; while none of the littoral parasitic species, such as Achnanthes, 

 Isthmia, Biddulphia, Striatella, and Synedra are found. 

 . 4th. It is worthy of notice that in the deep soundings not a single 

 specimen was found of Polythalamia belonging to the Plicatilia of 

 Ehrenberg, (Agathistiques of D'Orbigny,) while a number of these 

 forms were found in the shallow soundings, and they are well known 

 to occur in vast quantities around the shores of Florida and the West 

 India Islands. This group of Polythalamia appears to have been cre- 

 ated after the deposition of the chalk formation, in which no trace of 

 such forms occurs, while they are very abundant in the tertiary depos- 

 ites. Their entire absence in the deep soundings, where vast numbers 

 of other Polythalamia occur, and their presence in littoral deposits, 

 would seem to indicate that for their abundant development compara- 

 tively shallow seas are necessary; thus affording additional evidence of 

 difference in the depths of the seas from which the cretaceous and ter- 

 tiary beds were deposited. 



5th, The deep soundings were all from localities which are more or 

 less under the influence of the Gulf stream, and it is not improbable 

 that the high temperature of the waters along the oceanic current may be 

 the cause of immense development of organic life, making its path, as 

 is shown by the soundings, a perfect milky way of Polythalamia forms. 

 The deposits under Charleston may have been produced under ih^ 

 similar influence of an ancient gulf stream. 



6th. From the presence of such great numbers of Polythalamia m 

 the deep soundings, there results a very large proportion of calcareous 

 matter, thus presenting a striking difference between them and the 

 quarlzose and felspathic sands nearer shore. 



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