TRIP LOP HYLLITES 



41 



Externals. — Curved ceratoid ; epitheca 

 rather smooth, with sparse encircling rugae ; 

 calyx deep, sloping toward cardinal quad- 

 rants; cardinal fossula on concave side; 

 major septa extend upon floor of calyx but 

 do not reach center; minor septa appear as 

 septal ridges. 



Transverse sections. — In late ephebic 

 state, thin major septa extend three-fourths 

 of the radius; cardinal fossula prominent; 

 minor septa very short. 



In middle ephebic stages, cardinal fos- 

 sula may be curved, with thickened area 

 at inner end where thin major septa meet; 

 minor septa as septal crests ; cardinal septum 

 very short. 



In late neanic or early ephebic stage 

 cardinal fossula is narrow, major septa fuse 

 around fossula ; alar pseudo-f ossula present ; 

 cardinal septum rather long; no minor 

 septa; tabulae present in all stages; dissepi- 

 ments sparse. 



Occurrence. — Localities 1, 14, 15, ?52, 

 67, 90. 



Material. — Specimens studied, 4. Mil- 

 ler's figured specimen (here designated the 

 holotype) University of Cincinnati No. 

 7391 ; Weller's cotypes, University of Chi- 

 cago No. 4705; Worthen's specimen (1890, 

 pi. 10, fig. lb), Illinois State Geological 

 Survey (Worthen collection) No. 2570 — 

 the others shown in figs. 1, la of pi. 10 are 

 missing. 



Remarks. — The above description is mod- 

 ified from data presented by Grove (1935, 

 pp. 347, 348). Zaphrentis wortheni Weller 

 was renamed Z. welleri by Grove because 

 the former name is a junior hononym of Z. 

 wortheni Nicholson. 



This species can be distinguished from 

 7\ cliff ordanus by the thin septa (rather 

 than thick short septa), by the presence 

 of minor septa in early ephebic stage, and by 

 the weakly developed cardinal fossula 

 present in an ephebic stage. The shape of 

 the fossula of T. exiguus in early ephebic 

 stage is the same as that in adult stages of 

 T. cliff ordanus, according to Grove (1935, 

 p. 348). 



Worthen's specimen has the characteristic 

 reddish-brown color of many Fern Glen 

 fossils; the locality on the label is merely 

 "Kinderhook, Monroe County, Illinois." 



Zaphrentis exigua of Keyes (1894, p. 

 112) and Moore (1928, pp. 97, 154, 195) 

 are omitted from the synonymy because 

 specimens cannot be located for checking; 

 it is highly improbable that these citations 

 are equivalent to Z. exigua Miller which 

 is based upon a single young specimen. In 

 the same lot with this specimen, but of 

 uncertain value as types (because of lack 

 of numbers or other identifying data), were 

 specimens of Meniscophyllum minutum and 

 Hapsiphyllum (n. subgen.) n. sp. 



Triplophyllites IDA (Winchell) emend. 

 Easton 



Plate 11, figures 3-6; Plate 17, figures 6, 7 



Zaphrentis Ida Winchell, 1865, [in part], Acad. 

 Nat. Sci. Philadelphia Proc, p. 111. 



Non Zaphrentis Idaf, Winchell in Safford, 1869, 

 Geology of Tennessee, pp. 441, 444. 



fZaphrentis Idaf, Winchell, 1870, Am. Philos. 

 Soc. Proc, vol. 11, p. 247. 



Zaphrentis Ida, Kindle, 1899, Bull. Am. Paleon- 

 tology, vol. 3, bull. 12, pp. 12, 176. 



Triplophyilum cliffordanum var. Iiespere Grove, 

 1935, Am. Midland Naturalist, vol. 16, p. 

 346, pi. 8, fig. 6; pi. 18, figs. 9-11. 



Externals. — Curved ceratoid to trochoid ; 

 epitheca moderately thick, with encircling 

 striae and rugae, rejuvenation and as- 

 sociated geniculation common, interseptal 

 ridges faint; calyx apparently deep. Great- 

 est diameter of holotype, 27 mm ; length of 

 convex side, 60 mm (incomplete). 



Transverse section. — Holotype in middle 

 ephebic stage (diameters 10.4 by 10.7 mm) 

 with approximately 26 major septa greatly 

 thickened, extending nearly to center ; cardi- 

 nal septum rather thin, long, occupying nar- 

 row fossula on concave side ; tabulae sparse. 



Paratype in late ephebic stage (diameters 

 15.6 by 16.4 mm), with 31 major septa; 

 cardinal septum very short, thin ; all septa in 

 cardinal quadrants thin; counter septum 

 longest, it and septa of counter quadrants 

 much thickened, some notably thickened 

 near tips ; minor septa rudimentary ; tabulae 

 sparse, four intersections in fossula, one 

 across center of corallite. 



Tangential section. — Edges of tabulae 

 concave upwards, 3 to 7 in 5 mm. 



Occurrence. — Localities 6, 12, 13. 



Material. — Specimens studied, 4. Holo- 

 type, University of Michigan No. 5396; 

 paratype, University of Michigan No. 

 23237; third original cotj'pe (Amplexus 



