P. E. Raymond — Fauna, of the Chazy Limestone. 359 



tocerium, Eospongia varians, Rafinesauina champlainensis, 

 Plcesiomys platys, Maclurites magna, Pliomerops canadensis, 

 and several cephalopocis are common. 



Division 3. — The Camarotoechia plena division is not very 

 well developed along the line of- the section at Chazy. The 

 thickness is 156 feet, but a large part of the strata is covered 

 with soil. At the base are about 25 feet of grey dolomite with 

 almost no fossils. The remainder of the rock, as far as exposed, 

 is an impure shaly limestone, abounding in Camarotoechia 

 plena. Zones 3 a , 3 & , and 3 C can not be distinguished just at 

 Chazy village, probably because the strata are so poorly ex- 

 posed. About 3 miles southeast of this point, however, in a 

 field near the lake shore, fine outcrops of zone 3 a occur, and 

 . here Glaphurus pustidatus, Amyhilichas minganensis, Illce- 

 nus globosus, and the cephalopods are common. 



Section, at Valcour Island. 



On Valcour Island, the whole of the Chazy is exposed, with 

 a thickness of 890 feet. In one section along the south end, 

 almost the entire thickness is shown, while nearly all the miss- 

 ing parts may be seen in other sections on the east and north 

 sides of the island. 



Division 1. — The strata of this division are well exposed on 

 the south end. The thickness is 314 feet. At the base is a 

 zone of sandstone and shale in which Lingula brainerdi is the 

 common fossil. Other fossils are rare, Isotelus harrisi and a 

 species of Eccyliopterus being the only ones thus far found. 

 Above this zone is that of Orthis acutiplicata, 10 feet in 

 thickness. 



The Scalites angidatus zone is not exposed on Yalcour 

 Island, the rocks usually containing it being absent at the peb- 

 ble beach on the south end of the island. The Lophospira 

 subabbreviata zone is not well developed, but may be indicated 

 by a fauna found on the middle of the west side. 



Division #.— The strata of this division are 406 feet in 

 thickness and are usually compact, dark blue and grey lime- 

 stones. The fossils are frequently coarsely silicified, but are 

 almost always difficult to extract. At the base, zone 2 a ,' the 

 Malocystites murchisoni zone, is well developed, and as the 

 fossils weather out in this locality, some 40 species have been 

 listed. 



While the rocks of this division usually afford poor collec- 

 tions, yet in favorable localities they are found to be extremely 

 rich in interesting species. Thus, one locality on the east side 

 of the island has yielded 60 species of fossils, among them such 

 rare trilobites as Asaphus marginalis, Isotelus f bear si, and 

 Remopleurides canadensis, and many species of pelecypods. 



