710 SCHUCHERT AND TWENHOFEL ORDOVICIC-SILURIC SECTION 



Feet 

 one largely of muddy bottoms. The fossils are plentiful and in 

 excellent preservation on Wreck Beach, the Gull Cape of Rich- 

 ardson. The section here beginning at the base is as follows : 



RhyncJionella fringilla-glacialis deds. 



Blue to gray shale with thin gray limestones 50 



Brownish gray nodular thin-bedded limestones 20 



Thick-bedded gray limestones with some corals 40 



Thin-bedded limestones and shales 30 



The shale zone or lower 50 feet has an abundance of Alveo- 

 lites laheclii, Favosltes gothlandiciis, F. cf. favosus, Rafines- 

 quina profunda, Schuchertella pecten, Rhipidomella cf. circula, 

 Rhynchonella glacialis, R. fringilla (both species are prolific). 

 From the limestone series are recognized Favosites goth- 

 landicus, Climacograptus n. sp., Brachyprion leda, Rhipidomella 

 circula, and Rhynchonella Mdens. 



D,s (^Dy-Ds). South shore. Gray and light blue thin-bedded lime- 

 stones and conglomerates with small flat pebbles in limestone 



matrix. Seen at Cape McGilverey 05 



The more common fossils are Pasceolus, Heliophyllum (6 

 inches long), Favosites gothlandicus, F. venustus, Haly sites 

 catcnulatHS, Climacograptus cf. ulrichi, Helopora fragilis, Schu- 

 chertella pecten, Trlplecia ortoni (first appearance and rare 

 here), StricMandinia lens (first appearance and rare here), 

 Atrypa reticularis (first time), Hyattella congesta (also the 

 var. quadricostata) , Rhynchonella Mdens, and small ostracoda 

 (common). 



D,s. North shore. These zones are well exposed in the cliff west of 

 Sand Top Bay. Here there are 150 feet of limestones and 

 shales. Between these strata and those of Wreck Beach there 

 is a concealed zone in which 50 to 70 feet of strata may be 

 hidden. The recognized fossils are Pasceolus, Favosites cf. 

 favosus, Rhynchonella fringilla (very rare), and StricMandinia 

 lens (common). 



Dg (nnDg-Dio) 01" Triplecia ortoni beds. South shore. Ash gray to 

 reddish gray thin-bedded limestones w^eathering to yellowish 



brown but generally whitish 92 



- Seen from 2i/^ miles west of Jupiter River to near the Jupiter 

 River Cliff. The fauna here listed is from the lower 65 feet 

 and the specimens are excellent. Among them are : BiloMtes 

 hilohus, Hedertella fausta ?, Leptwna rhomhoidalis, Plectam- 

 honites n. sp., Schuchertella pecten, Triplecia ortoni (common, 

 a variety of the Ohio form), Pentamerus cf. ohlongus (an 

 elongate early form), Clorinda n. sp. (not fornicata), Atrypa 

 cf. rugosa, A. reticularis, Anoplotheca hemispherica (first ap- 

 pearance), Nucleospira n. sp. (also in E3), Platyceras niagaren- 

 se, Illwnus cf. daytonensis, Acaste orestes, Cheirurus nuperus ? 



