EARLY OEVONIC HISTORY OF NEW YORK AND EASTERN NORTH AMERICA 23 



lines and somewhat swollen at the top near the suture. It is an expression 

 unusual at this early age though well known in Carbonic shells of similar 

 type and as the departure from H. enjalrani is alone in the clustering 

 of the concentric growth striae into pilae, I should regard the shell a varietal 

 expression of that species. 

 Horizon. No. 12. 



Holopea cf. antiqua Vanuxem var. pervetusta Conrad 



Plate i, figures 14-16 



See Hall, Palaeontology of New York. 1859. 3:294, pi. 54, fig. 2, 3 



The shells of this type from Dalhousie are essentially like those figured 

 by Hall as Holopea antiqua but have the less marked difference in 

 size of body whorl which brings them into closer resemblance to the variety 

 cited but which was not well known to Hall. These shells are common at 

 Dalhousie, have uniformly convex whorls 3 to 4 in number, the last being 

 regularly rounded and transversely or concentrically striate. The aperture 

 is round or slightly oblique and the inner lip excavate. 



Horizon. No. 13. 



Coelidium strebloceras Clarke 



Plate 2, figures 7-9 



Coelidium strebloceras Clarke. N. Y. State Mas. Bui. 107. 1907. p. 189 



An extremely elongate and terete shell with not less than 20 volutions 

 at full growth. The best preserved specimen has a length of 70 mm, and a 

 width at the base of 1 1 mm. The latter whorls display a sharp median angu- 

 lation with a moderately broad and distinct slit band from which the slope to 

 the suture is abrupt, more distinct and flattened above, more convex below. 



This singularly delicate " Murchisonia" carries to an extreme the 

 expression presented by some of the species described by Hall from the 

 Guelph and by Lindstroem from the Gothlandian. 



Horizon. No. 1 1. 



Horizon. No. 11. 



Coelidium tenue Clarke 



See page 99 



Melissosoa compacta (Hall) 



Plate 2, figures 1-6 



Loxonema ? compacta Hall. Palaeontology of New York. 1S59. 3:297, pi. 54, 

 fig. 12 



Under the name cited Professor Hall described a shell from the Lower 

 Pentamerus (Coeymans) limestone of Schoharie, N. Y., which is peculiar 



