their neighbourhood, and have requested me to describe the new species 

 collected by them. At this localit}'- Palaopliycus incijAcns, Obolella 

 cingulata, Olenelhis Vermontana and 0. Thomjjsoni occur in the black 

 slates conformably interstratified with the sandstones and magnesian lime- 

 stones which constitute the principal mass of the formation. It Anil be 

 observed that several other species are also found here ; but the prevailing 

 forms are the four above mentioned, and, as they are most abundant in 

 the limestones of the Straits of Belle Isle, there can be little doubt that 

 the two deposits, altliough 860 miles distant from each other, are of the 

 same age. The occurrence of Scolithus linearis and the general aspect 

 of the fossils, also show that these rocks must be very nearly, if not 

 exactly, in tlie same geological horizon with the Upper Primal sandstones 

 and slates of Pennsylvania. 



PLzVNT^. 



Scolithus linearis. (Hall.) 



Scolithus linearis.— {Rail.) PaL, N. Y. VoL I, PI. I. Figs. 1, a, b, c. 



This species occurs at Anse au Loup in the sandstone, but I have not 

 detected it in the limestone of that locality. The form differs from tlie one 

 which is so common in the Potsdam sandstone of Canada in being larger 

 and straighter. It is perfectly identical with that of the Upper Primal 

 sandstone of Pennsylvania, and also with that of the Potsdam sandstone 

 of Tennessee. (Formation III of Prof. Saiford.) 



Pal^ophycus incipiens. (N. sp.) 



Description. — This species consists of elongated straight or slightly 

 curved stems from half an inch to three-fourths of an inch in width. The 

 transverse section is irregularly oval, with two acute edges, but it is prob- 

 able that this flattened form is due to compression. Although numerous 

 specimens lying in the rock were examined, no indication of branching 

 was observed. The specimens are usually from four to six inches in length, 

 but some are more than one foot. They occur abundantly on the surface 

 of certain strata, and the specimens from Anse au Loup are perfectly iden- 

 tical with those which abound in tlie slates near Swanton in Vermont, 

 holding Conocephalites, Olenellus Thonipsoni, 0. Vermontana, kc. 



Localltij and Formation. — Anse au Loup, on the north shore of the 

 Straits of Belle Isle ; sandstone of the Potsdam group. Also 1^ mUe 

 east of Swanton, in the State of Vermont, in rocks of the same age. 

 Collectors. — J. Richardson, Ilcv. J. B. Perry, and Dr. G. M. Hall. 



