62 



CHOUTEAU CORALS 



Mural pores may be present where tubes are in 

 contact, but generally occur only where buds are 

 given off. Septa rudimentary, represented by 

 vertical ridges. Scattered tabulae in some species. 

 (Stewart, 1938, p. 78.) 



Genotype. — Aulopora serpens Goldfuss, 

 1829. 



Occurrence. — Widely distributed, Ordo- 

 vician to Carboniferous. 



Aulopora? sp. 



Plate 17, figure 11 



Occurrence. — Locality 8. 



Material. — Specimens studied, 1. Univer- 

 sity of Chicago No. 47246. 



Remarks. — One specimen with curved, 

 evenly expanding, prostrate corallites con- 

 nected by thin tubes (stolonal budding) near 

 their bases was observed. The exteriors are 

 smooth and the corallites all face in the 

 same direction. The colony is not attached. 



Genus Cladochonus McCoy, 1847 



Diagnosis. — Corallum compound, with a reptant 

 ring of corallites proximally, from which free 

 branches arise; individual corallites, trumpet- or 

 pipe-shaped, and in contact only at point of origin, 

 each giving rise to another by lateral increase 

 through the wall of the expanded calice; each has 

 a thick peripheral stereozone of laminar, some- 

 times reticulated, sclerenchyme ; neither tabulae 

 nor septal spines are seen in the narrow lumen, 

 but longitudinal (Pseptal) ridges may appear in 

 the calices. (Hill and Smyth, 1938, p. 127.) 



Genotype. — Cladochonus tenutcollis Mc- 

 Coy, 1847. 



Occurrence. — Hill and Smyth (1938, p. 

 128) give the occurrence as upper Middle 

 Devonian and Upper Devonian of North 

 America and Germany; Lower Carbonifer^ 

 ous of North America, western Europe, 

 Russia, and eastern Australia; Middle and 

 Upper Carboniferous of Russia; Permian 

 of Western Australia, Timor, China, and 

 Jugoslavia. 



Remarks. — Many American species have 

 been referred to Monilopora Nicholson and 

 Etheridge, 1879, but Girty (1925), pointed 

 out on erroneous ground that Cladochonus 

 is a senior synonym of Monilopora. Hill 

 and Smyth (1938, p. 125) arrived at the 

 same conclusion but for different reasons. 

 Pyrgia Milne-Edwards and Haime, 1851, 

 is a junior subjective synonym of Cladocho- 

 nus. For the arguments regarding the status 

 of these genera, see Girty (1925) and Hill 

 and Smyth (1938). Monilipora is an er- 

 roneous emendation of Monilopora. 



Cladochonus Striatus Easton, n. sp. 

 Plate 13, figure 5 ; Plate 17, figures 4, 5 



Externals. — Colonies of medium size, 

 rather straight, new corallites budding from 

 parent about midway on convex side, facing 

 alternately in opposite directions, lying in 

 one plane ; three or four corallites con- 

 nected by common canal, generally occur on 

 partly overlapping crinoid stems; fronds 

 arising from first circle of corallites, pre- 

 sumably extended directly away from crin- 

 oid stem; calyces oval; corallites curved^ 

 evenly expanding to calyx rim, with pro- 

 nounced striae on epitheca. 



Largest frond 35 mm in length; indi- 

 vidual corallites about 5 mm long on convex 

 side and 3 or 4 mm on concave side; calyces 

 about 2.3 mm in diameter. 



Comparison. — C. striatus differs from C. 

 beecheri (Grabau) in being smaller, having 

 more linear colonies, and in being striate. 



Occurrence. — Locality 8. 



Material. — Specimens studied, 12. Holo- 

 type and paratypes. University of Chicago 

 Nos. 9678 and 9769, respectively. 



Position Unknown 



COLEOPHYLLUM ? GREENI Rowley 



Plate 15, figures 1-4 



Coleophyllum? greeni Rowley, 1901, Am. Geolo- 

 gist, vol. 27, p. 352, pi. 28, figs. 53-56. 



Description. — "This coral is elongated, 

 curved and without septa (lamellae). The 

 cup is shallow. The entire fossil is made up 

 of a series of invaginated tabulae, as seen 

 on the weathered specimens. The outer sur- 

 face is comparatively smooth except near 

 the calix where the edges of the tabulae 

 remind one somewhat of Cystiphyllum." 

 (Rowley, 1901, p. 352.) 



Occurrence. — Locality 29. 



Material. — Apparently two or more speci- 

 mens were known to Rowley, but the writer 

 understands they are not now available for 

 study. 



Remarks. — Rowley called this species 

 ^^Chonophyllum greenei" in the explanation 

 of the plate. The writer defers offering an 

 opinion as to the taxonomic position of this 

 species until the types or comparative mate- 

 rial can be studied. The figures resemble 

 stony bryozoa or Syringopora as much as 

 they do Coleophyllum or Chonophyllum 



