5'2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I45 



is more depressed, the naked zone in interambulacrum 5 is wider 

 (text fig. 42), and phyllode III is wider. 



R. evergladensis is similar in many of its characters to R. pacificus 

 (A. Agassiz), a species living off the west coast of the United 

 States, but is distinguished by its wider petals and more steeply slop- 

 ing posterior margin. 



R. evergladensis is distinguished from Rhyncholampas sabistonen- 

 sis (Kellum) by its higher and narrower test. Cooke (1959, p. 57) 

 considered the two species synonyms. 



Occurrence. — Tamiami formation (typical), loc. 9, 11, 13, 15, 16, 

 18, 19. 



Tamiami formation (barnacle-echinoid-oyster facies), loc. 26, 27. 



Types. — Lectotype, herein designated, U.S.N.M. 37329 (Mans- 

 field, 1932, pi. 18, figs. 1-3), U.S.G.S. 11177; figured specimens, 

 U.S.N.M. 648145-9, loc. 9. 



AGASSIZIA PORIFERA (Ravenel) 



Plate 16, figures 1-2; Plate 18, figures 1-5; text figures 51-58 



Brissopsis poriferus Ravenel, 1848, Echinidae, Recent and fossil, of South Caro- 

 lina, p. 4, figs. 5, 6. 



Agassizia porifera (Ravenel). McCrady, in Tuomey and Holmes, 1857, Pleio- 

 cene fossils of South Carolina, p. 5, pi. 1, figs. 5-5b; pi. 2, figs. 4, 4a. 



Agassisia porifera (Ravenel). Cooke, 1942, Journ. Paleont., v. 16, no. 1, p. 45. 



Agassizia porifera (Ravenel). Cooke, 1959, U. S. Geol. Surv. Prof. Paper 321, 

 pp. 74-75, pi. 31, figs. 1-8. 



Diagnosis. — Species characterized by large inflated test. 



Material. — Thirty-seven specimens. 



Shape. — Large, largest specimen 79 mm long, 76 mm wide, 64 mm 

 high; broad (text fig. 57), with greatest width at center or slightly 

 posterior; moderately to highly inflated, height varying from 69 to 

 90 percent of length (text fig. 58), with highest point anterior of 

 center slightly posterior of apical system ; marginal outline angular 

 with slight anterior, posterior truncation ; adoral surface moderately 

 inflated, in some specimens keel developed in midline of interam- 

 bulacrum 5. 



Apical system. — Anterior, ethmolytic (text fig. 56), madreporite 

 extending posteriorly, sutures between genital plates not visible. 



Ambulacra. — Ambulacrum III not petaloid, in very slight groove 

 not extending to margin ; anterior paired petals. II, IV, narrow, de- 

 pressed in groove, long, when viewed from above extending almost 

 to margin, when viewed from side extending midway from top to 



