GEOLOGY AND PALEONTOLOGY OF THE CANAL ZONE. 345 



U. S. Naval Reservation, Guantanamo, altitude about 400 feet a. t., in 

 beds of the age of the Antigua formation, collected by O. E. Meinzer. 

 Type— No. 324784. U.S.N.M. This species differs so markedly 

 from the other West Indian species of P.ocillopora that comparisons 

 with the other species seem unnecessary. 



Genus MADRACIS Milne Edwards and Haime. 



1849. Axhelia Milne Edwards and Haime, Comptes Rend., vol. 29, p. 69. 

 1849. Madracis Milne Edwards and Haime, Comptes Rend., vol. 29, p. 70\ 

 1861. Reussia Duchassaing and Michelotti, Mem. Corall. Ant., p. 63 (of reprint). 

 1871. Pentalophora Saville-Kent, Proe. Zool. Soc. London for 1871, p. 283. 

 1884. Madracis Duncan, Linn. Soc. London Journ., Zool., vol. 18, p. 45. 



1900. Madracis Vaughan, U. S. Geol. Survey Mon. 39, p. 128. 



1901. Axhelia Vaughan, U. S. Fish Commission Bull, for 1900, vol. 2, p. 29"4. 



1902. Madracis Verrill, Conn. Acad. Arts and Sci. Trans., vol. 11, p. 108. 



Type-species. — Madracis asperula Milne Edwards and Haime. 



MADRACIS MIRABILIS (Duchassaing and Michelotti). 



1861. Stylophora mirabilis Duchassaing and Michelotti, Mem. Corall. Ant., 



p. 62 (of reprint), pi. 9, figs. 6, 7. 

 1901. Axhelia mirabilis Vaughan, U. S. Fish Commission Bull, for 1900, vol. 2, 



p. 295, pi. 1, figs. 3, 3a. 



A single fragment of a branch from Limon, Costa Rica, is 23 mm. 

 long, 2 mm. in diameter at the lower end, and 3 mm. in diameter 

 just below trifurcation at the upper end. The fragment is slightly 

 arcuate in form, not quite straight, and is not so crooked as is usual 

 in the specimens of M. mirabilis with which I have compared it. 

 The septa are less exsert around the calicular margins then is usual 

 in the species. Although there are the differences indicated, they 

 are of the kind that may be produced by vegetative causes. 



Locality and geologic occurrence, — Costa Rica, hills of Port Limon, 

 No. 669 of H. Pittier collection; geologic horizon not known. 



Cuba, station 3461, gorge of Yumuri River, Matanzas, 19 frag- 

 ments collected by T. W. Vaughan in a marl of lower Miocene 

 (Bowden) age. 



These fragments perhaps should be referred to a new species,' 

 but they appear more probably to be only a variant of M. mirabilis. 



Family ASTROCOENIIDAE Koby. 



Genus ASTROCOENIA Milne Edwards and Haime. 



1848. Astrocoenia Milne Edwards and Haime, Comptes Rend., vol. 27, p. 469. 

 1900. Astrocoenia Gregory, Palaeontol. Indica, ser. 9, vol. 2, pt. 2, p. 59. (Syn- 

 onymy and elaborate discussion.) 



Type-species. — Astrea numisma Def ranee. 



Besides the five species of Astrocoenia recognized in the present- 

 paper, I have described one under the name of Stylocoenia duerdeni 



