360 Professor J. W. Bailey on 



any of the others ; while Textilaria atlantica, although pre- 

 sent, 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, Gallionella 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. 



4:th. 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 created after the 

 deposition of the chalk formation, in which no trace of such 

 forms occurs, while they are very abundant in the tertiary 

 deposits. 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, comparatively shallow seas are neces- 

 sary ; thus affording additional evidence of difference in the 

 depths of the seas, from which the cretaceous and tertiary 

 beds were deposited. 



5M. The deep soundings were all from localities which are 

 more or less under the influence of the Gulph stream, and it 

 is not improbable that the high temperature of the waters 

 along the oceanic current may be the cause of immense de- 

 velopment 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 

 the similar influence of an ancient gulf stream. 



6th. From the presence of such great numbers of Poly- 

 thalamia in the deep soundings, there results a very large 

 proportion of calcareous matter, thus presenting a striking 

 difference between them and the quartzose and felspathic 

 sands nearer shore. 



7t/t. The littoral sands obtained in shallow soundings at 

 first view appear to afford little promise of affording any 



