18 GEOLOGY AND PALEONTOLOGY OF THE WEST INDIES. 



though both professedly examined the same material, preserved in the 

 Museum d'Histoire Naturelle of Paris. Foslie at first considered the 

 plant to belong to the Squamariaceae. 1 In case that anyone should 

 find adequate grounds for combining Lithoporella pacifica with the 

 forms brought together above, it may be remarked that the name 

 pacifica would appear to enjoy priority rights over melobesioides. 

 However, there is a still earlier name of probable applicability that 

 must be considered if a " broad" view of species is to be accepted and 

 if the fossil and recent forms are to be looked upon as representing a 

 single species. This is the Lithothamnium tenuiseptum of Capeder, 2 

 from the Pliocene of Monte Mario (near Rome?), Italy. Capeder's 

 figure of the microscopic structure is rather diagrammatic and sketchy 

 and we do not feel so confident that it represents our Leeward Islands 

 fossil as we do in regard to Foslie's more convincing figures of his L. 

 melobesioides. Capeder describes the cells as 60 /x by 18 /x and figures 

 them as 3 times as high as broad, a proportion that is of only occasional 

 occurrence in L. melobesioides as we know it. Conceptacles are de- 

 scribed as 404 m by 202 /x, but if two cavities shown in his detailed figure 

 are the supposed conceptacles, and if the relations of the surrounding 

 cells are correctly represented, it may be suspected that these cavities 

 represent holes of boring animals or other fortuitous lacunae rather 

 than conceptacles. 



The West Indian fossils that we are referring to Lithoporella melo- 

 besioides, as is usual with the species of Foslie's subgenus Eulitho- 

 porella, are very commonly overgrown by other calcareous algae, 

 sometimes lying in alternating layers with such algae, and are not 

 always visible in a surface view. 



The collections made in the Leeward Islands by Dr. Vaughan include 

 several representatives of the Lithothamnieae in addition to the 5 

 species described and discussed in the foregoing report, but we have 

 not felt justified in giving them names, owing to the limited quantity 

 or unsatisfactory preservation of the material or to lack of success in 

 obtaining sufficiently instructive sections. 



Deserving special mention among these specimens left undetermined 

 is one, a, from station No. 6881, bluff (Oligocene) on north side of Wil- 

 loughby Bay, Antigua, which has intertangled subterete branches 

 1.5 to 3.0 mm. in diameter. 



A specimen from station No. 6854, Rifle Butts (Oligocene), Antigua, 

 shows one or more species of thin crustaceous Lithothamnieae closely 

 adherent to old millepores or corals. In general habit these resemble 

 the recent Goniolithon solubile Foslie and Howe, which now incrusts 

 dead corals and millepores throughout the West Indian region. 



1 Kgl. Norske Vidensk. Selsk. Skr. 1901, No. 2, p. 19. 



1 Malpighia, vol. 14, 1900, p. 181, plate vi, figs, 17a, 176. 



