698 SCHUCHERT AND TWENHOFEL ORDOVICIC-SILURIC SECTION 



Zones Bi and Bg. On the south shore but few fossils are seen in these 

 zones, and the same is true for zones B3-B5, all of which species are also 

 those of Division A. On the north shore zones B^ and Bg are of less pure 

 limestone with more shale and therefore yield more fossils. These may 

 be seen from White Cliff eastward to the trap dikes of West Cliff. The 

 more diagnostic fossils of these zones (especially of the north shore) are 

 the following: Favosites (?) prolificus, CUmacograptus putillus, Reteo- 

 crinus fimhriatus, 8ceptropora facula, Dinobolus n. sp. (Bg), Dinorthis 

 subquadraia, Strophomena neglecia, 8. hecuba, Rhyncliotrema anticosti- 

 ensis, R. perlamellosa (common here), Catazyga antic ostiensis, Byssony- 

 chia subrecta, Billingsites canadensis, Isotelus alacer (of susce group), 

 Cheirurus icarus, and Ceraurus pleurexanthemus. 



Zones B3, B4, and B5. On the south shore these zones are thin-bedded 

 limestones with almost no shale and furnish but very few fossils, while on 

 the north shore they are made up of an alternation of shales and lime- 

 stones abounding in fossils. At Observation Cliff these strata may be 

 studied to best advantage where there are 15 bands of limestone each 

 about 10 feet thick, alternating with thin limestone and shale zones each 

 about 20 feet in depth. The cliff here is about 350 feet high, at the 

 bottom of which is the "track bed" making the top of Division A. No 

 Beatricea were seen here, yet on the south shore they appear for the first 

 time in Bg, or 188 feet above the "track bed." Zones B3-B5 have there- 

 fore on the north shore fully twice as great a thickness as the equivalent 

 beds near the West End lighthouse of the south shore. At Cape Henry 

 the highest beds of zones B3-B5 may be seen, here consisting of 200 feet 

 of thin-bedded limestones of a drab or grayish brown color. 



The fauna of these zones is a large one, of which may be mentioned 

 Streptelasma angulatum, Calapoecia crihrifo7'mis, Columnaria halli, Palas- 

 terina rugosa, Dendrocrinus latihrachiatus, Reteocrinus fimbriatus, first 

 abundance of Nematopora. Arfhroclema, and Helopora, CornulHes rich- 

 mondensis, Lingula quadrata, Dinoholus n. sp. (rare), Dalmanella meeH, 

 Dinorthis suh quadrata, Hehertella maria, Rafinesquina imbrex, R. squa- 

 mata or ceres, Strophomena neglecta, 8. fluctuosa, 8. hecuba, Leptcena 

 nitens, Rhynchotrema perlamellosa, R. anticostiensis, Rhynchonella (?) 

 janea, Catazyga anticostiensis (ranges throughout these zones on north 

 and south shores), Conradella pannosa, Billingsites canadensis, Cheirurus 

 icarus, Calymene callicephala, Illcenus alacer, etcetera. 



Zone Bg. On the southwest end of Anticosti this zone is seen in the 

 abandoned sea cliff to the west of West End lighthouse. Here it is 102 

 feet thick. On the northeast end of the island the equivalent strata are 

 well exposed at Battery Point. At both of these places the Beatricea 



