SPENCER — NIAGARA FOSSILS. 609 



cross the sides of the shell and bend abruptly at medial lines. 

 These are again traversed by shallow longitudinal striae situated 

 closer together than the transverse ridges, but which do not 

 penetrate them to a depth of the separating transverse grooves. 

 But, where the longitudinal slriag cross the transverse channels, 

 there are punctures in the grooves ; and where they cross the 

 ridges, there is a depression in the centre of the ridges. 



I have only seen one specimen, which is not entire. The frag- 

 ment is 13 centimetres long, with two sides partly remaining ; the 

 greatest width at base of side (visible) is about five centimetres. 

 In some places the shell is crushed, bringing the ridges and 

 grooves together very closely in a wrinkled manner ; and, where 

 not crushed, the surface presents a wrinkled appearance. There 

 are ten transverse ridges and furrows in one centimetre of length. 

 The longitudinal strias and the punctures in the transverse grooves 

 are situated one-ha'f millemetre apart. 



For^nation and Locality — This species was obtained in the 

 Niagara limestone at Hamilton, Ontario, and presented to me by 

 Mr. Turnbull of that city. 



CONULARIA WILKINSI, nOV. sp. 

 Plate 8. Fig. 3. 



Shell short, broad, pyramidal ; each side marked with an in- 

 conspicuous medial depression ; transverse strias very fine and 

 arranged in a direction from edge to edge of valve, but bending 

 at a considerable angle away from the apex in the region of the 

 medial depression; punctures in the shallow stris of interior sur- 

 fiice of shell present, but indistinct. 



This shell is usually as broad, or broader, than long. Length 

 is usually between two and three centimetres. There are from 30 

 to 40 transverse strise in every centimetre of length. Never more 

 th.Tn two adjacent valves of shell are exposed. 



Pormation and Locality. — Niagara limestone at Hamilton, 



Ontario. 



Orthoceras bartonense. 



Plate 7. Fig. 7. 



This shell is cylindrical, small, and tapering very slightly. The 

 siphuncle is apparently subcentral. The surface is strongly annu- 

 lated, and the crests are somewhat angular and situated at about 

 2.5 millimetres apart. The annular crests are marked by swell- 

 ing waves (giving a nodular appearance on the margin), whose 



