GEOLOGY AND PALEONTOLOGY OP THE CANAL ZONE. 415 



Columella trabecular, false, fairly well developed. 



Thin endothocal dissepiments abundant. 



Asexual reproduction by marginal fission. 



Locality and geologic occurrence. — Mexico, hill 4 miles east of San 

 Rafael Ranch, State of Tamaulipas, collected by W. F. Cummins 

 and J. M. wSands in the Oligocene San Rafael formation of Durable,* 

 in association with Aniiguastrea cellulosa (Duncan) Vaughan. 



Type— Cat. No. 324995, U.S.N.M. 



This specimen closely resembles Astroria antiguensis Duncan.^ I 

 have a photograph (see pi. 131, fig. 4) of Duncan's type (No. 12936, 

 Coll. Geol. Soc. London), and because of the resemblance, I furnished 

 Mr. Durable the narae Goniastrea {?) antiguensis (Duncan), as given 

 in his papers cited. Subsequent study of the photograph and further 

 coraparisons with specimens from Antigua lead me to believe that 

 Astroria antiguensis is in reality a fungid coral, and is probably based 

 on a silicified specimen of CyatTiomorplia antiguensis (Duncan) 

 Vaughan in which the corallites are deformed by crowding. That 

 adjacent corallites are separated by costate intercorallites areas is 

 clear on most of this photograph; and apparently there are both 

 intercostal and mural synapticulae. For additional notes on Astroria 

 antiguensis see page 466 of this paper. 



FAVITES POLYGONALIS (Duncan). 



1863. Astroria polygonalis Duncan, Geol. Soc. London Quart. Joum., vol. 19, 

 p. 424, pi. 14, fig. 6, 1863. 



Besides F. mexicana, the only other definitely known species of 

 Favites in the American older Tertiary formations is F. polygonalis 

 (Duncan) Vaughan, which is very abundant in Antigua. The calices 

 of F. polygonalis are much larger than in F. mexicana, the smallest 

 size usually being 15 mm., rarely as little as 14 mm. in diameter; 

 range in diameter from the size just stated up to 23 mm. wide by 

 35 mm. long, an extraordinarily large calice. The lesser diameter 

 of a calice is usually between 15 and 20 mm. The calices are exca- 

 vated, depth 8 to 10 mm., separated by acute walls. Septa in 4 

 or 5 sizes, thin, rather distant, about 8 within 1 cm. In many 

 specimens there is a more or less flattened zone around the colum- 

 ullar fossa, which is bounded by the rather steep inner ends of the 

 septa. In F. mexicana, 9 septa were counted within a linear dis- 

 tance of 5 mm., being twice as many within the same distance as 

 there are in F. polygonalis. Cooke and Mansfield collected in the 

 base of the Chattahoochee formation, station 7078, 8 miles below 

 Bainbridge, Georgia, a species of Favites that seems to be the same 

 as the Antiguan specimens of F. polygonalis with small calices. 



1 See p. 206 for additional notes. 



2 Geol. Soc. London Quart. Joum., vol. 19, p. 425, 1863. 



