110 ROYAL SOCIETY OF CANADA 
Sculplure.—The texture of the inclosing matrix is rather too coarse 
to show the sculpture distinctly, but undulations of growth show only a 
moderate arch to the dorsal striæ and the lip. A few horizontal thread- 
like ridges can be seen on the ventral side, but a fine granulation seems 
to be the chief ornamentation on both sides. 
Size (including the supposed larval tube).—The length is 43 mm. 
and the width 4 mm. Of the length 13 mm. belong to the larval tube, 
13 mm. to the visceral cavity, and 17 mm. to the brachial area. The 
different parts show the usual variation in apical angle, the most rapid 
enlargement in the tube occurring along the visceral area (including 
the camerated part). 
Horizon and Locality—In somewhat hard sandy shale of Div. 1c 
at Rodney St., St John (West). Not rare. 
This shell does not differ much in general form from Orthotheca 
Hermelini, Holm, but the projecting lip distinguishes it. A shell from 
near the horizon of H. gracillimus is H. (O.) leretiuscula, Linds; but in 
that species the striæ on the dorsal side are only weakly curved, and the 
transverse section is round, while in this the dorsal side is flattened, as in 
H. (O.) de Geert, Holm. H. (0.) Stylus, Holm, of the P. Forchham- 
meri zone, also has the striæ only slightly arched, and has a nearly 
round transverse section. 

