494 



BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



Calices sunken between a rather regular mural network, diameter of 

 calicular openings 1.5 to 2.5 mm., diameter measured between mural 

 summits 2.5 to 3.5 mm., depth about 0.75 mm., separating walls 

 from 0.75 to 1.25 mm. wide. The walls are rather flat-topped and 

 are composed of costal prolongations of the septa joined together by 

 synapticulae. In places there is considerable intercorallite reticu- 

 lum, but it does not form protuberances between the calices; where 

 the surface is well preserved, subequal costae extend across the walls. 



Septa of normal gonioporid arrangement, in the typical formula; 

 above the bottom of the calices they are narrow, extending down 

 the insides of the walls as short ribs, which bear about three inwardly 

 projecting dentations; at the bottom of the calice they widen and 

 the primaries and secondaries extend to the columellar tangle. Well 

 developed paliform lobes occur just inside the junction of the ter- 

 tiaries with the secondaries and form a crown around the periphery 

 of the columellar tangle. Width of interseptal loculi less than the 

 thickness of the septa. 



Columellar tangle well developed, large, forms a flattish bottom 

 to the calices, width about one-half the calicular diameter. 



Locality and geologic occurrence. — Canal Zone, station 6016, quarry, 

 in the Emperador limestone, Empire, collected by T. W. Vaughan and 

 D. F. MacDonald. 



Anguilla, stations 6893, 6894, 6966, 6967, all coralliferous beds at 

 Crocus Bay; station 6969a, bottom bed, Road Bay, collected by 

 T. W. Vaughan. 



Type— No, 325049, U.S.N.M. 



This species really should have been based on the Anguillan mate- 

 rial, of which I collected 34 identifiable specimens. In fully devel- 

 oped colonies the branches are subcircular or elliptical in cross 

 section, and range from 30 to 55 mm. in diameter. The distance 

 between mural summits ranges up to 4.5 mm. but is usually less. 



GONIOPORA CANALIS, new species. 



Plate 146, figs. 1, 2, 3. 



Corallum composed of compressed branches. The following are 

 measurements : 



Dimensions of branches of Goniopora canalis. 



Branch No. 



Length. 



Greater di- 

 ameter of 

 lower end. 



Lesser di- 

 ameter of 

 lower end. 



Maximum 

 width. 



1 



mm. 

 41 

 41 



mm. 

 20 

 20 



22 



mm. 

 6.5 

 12 

 8 

 7.5 



mm. 

 30 



2 



28 



3. 



35 



4 





20+ 





1 





