16 GEOLOGY AND PALEONTOLOGY OF THE WEST INDIES. 



together very gradually) are usually about 26 ix long and twice as long 

 as broad; in L. (?) molare the corresponding cells are about 15 to 18 fi 

 long and scarcely longer than broad. Our best sections of L. (?) molare 

 are, however, somewhat oblique and may not do full justice to the 

 length of the cells. In L. platyphyllum the much flattened branches 

 are thinner and less massive, being only 1.25 to 2 mm. thick. 



Lithoporella melobesioides (Foslie) Foslie. 

 (Plate 6.) 



Lithoporella melobesioides (Foslie) Foslie, Kgl. Norske Vidensk. Selsk. Skr., 1909, No. 2, p. 59. 

 Mastophora melobesioides Foslie, Kgl. Norske Vidensk. Selsk. Aarsber. for 1902, p. 24, 



1903; Siboga Exped. Monog. 61, 1904, p. 75-77, figs. 30-32. 

 Mastophora {Lithoporella) melobesioides Foslie, Kgl. Norske Vidensk. Selsk. Skr., No. 7, p. 



19, 1908; op. cit., No. 2, p. 52, 1909. 

 Mastophora (Lithoporella) atlantica Foslie, Kgl. Norske Vidensk. Selsk. Skr., No. 2, p. 27, 



1906. 

 Lithoporella atlantica Foslie, Kgl. Norske Vidensk. Selsk. Skr., No. 2, p. 59, 1909. 

 Mastophora (Lithoporella) conjuncta Foslie, Kgl. Norske Vidensk. Selsk. Skr., No. 6, p. 30, 



1907. 

 Lithoporella conjuncta Foslie, Kgl. Norske Vidensk. Selsk. Skr., No. 2, p. 59, 1909. 



The following is a description of the fossil West Indian forms of this 

 species: 



Monostromatic thalli occurring singly, or 2 to 8 of them irregularly, loosely, 

 or now and then rather compactly superposed; cells (19) 23 to 57 /* high and 

 13 to 39 y. wide, 1 to 3 (mostly 1.5 to 2) times as high as wide, in a vertical 

 section appearing for the most part distinctly rounded at the angles and occa- 

 sionally suborbicular and submoniliform; conceptacles unknown. 



On and intercalated among other calcareous algae incrusting a fossil 

 millepore (?), in "top bed" (upper Oligocene), Crocus Bay, Anguilla, 

 T. W. Vaughan, station No. 6967 (plate 6, fig. 2); with millepore (?), 

 Crocus Bay Hill (upper Oligocene), roadside, descent to Crocus Bay 

 from valley, Anguilla, T. W. Vaughan, station No. 6893; intermingled 

 with other calcareous algae from bluff (Oligocene, middle of Antigua 

 formation) on north side of Willoughby Bay, Antigua, T. W. Vaughan, 

 station T$o. 6881; and intercalated with Lithophyllum homogeneum in 

 limestone (upper Eocene or lower Oligocene) from above head of 

 Governor's Bay, St. Bartholomew, T. W. Vaughan, No. 6923 (plate 6, 

 fig. 1), February 22, 1914. 



The description, as given above, is drawn from the fossil West 

 Indian specimens cited, but it would require only very slight changes 

 in the cell measurements to make it include all of the forms, recent and 

 fossil, described by Foslie under the names cited above. On first 

 meeting with this plant in one of the Anguilla specimens from station 

 No. 6967, it was our impression that it might be considered specifically 

 distinct from all of the forms described by Foslie in its shorter cells 

 (19 to 42 /z in the specimen cited), but the subsequent discovery of the 

 other specimens showed both a great variety of forms and sizes of cells 



