12 
outer surface, the outline at the opposite end of the diameter being semi- 
circular, the sides of the prolonged portion varying from flat to slightly 
convex. Cup deep, almost straight sides. The characteristic feature 
of the species, however, is the prolonged cardinal septum, a feature which 
becomes accentuated with age. In many cases the septum itself is broken, 
leaving a deep, pronounced fossula. Septa alternating, shorter ones 
almost rudimentary, only seen in the younger examples, becoming amal- 
gamated with the thickened wall in older specimens. Primary septa 
35 to 55 twisting slightly at the centre, 10 to 14 on each side of the cardinal 
septum directed toward the centre at different angles. Upper septa 
fan-shaped. Dissepiments numerous, becoming more or less contiguous 
in the visceral chamber, but never developed into true tabulae and with the 
twisted ends of the primary septa forming a very cellulose structure which 
rises above the level of the cup floor in a persistent but not very pronounced 
pseudo-colufmnella. The twisted ends of the septa show the development 
of delicate, little, plate-like standards that flaunt themselves at various 
angles, making a remarkable and beautiful interior shown in the bottom 
of the cup of any well-preserved specimen. 
S. prolongatum in outward form is quite distinct from any other 
described species. The closest in form is S , trilobatum, but its proportions 
are different and the Rocky Mountain species, although having in a much 
more pronounced degree the angular lobe due to the prolonged cardinal 
septum, lacks the two other side lobes with the troughs between, and 
it has nothing of the approximately equilateral form of the Stony Mountain 
species. 
Horizon and Locality. Richmond: Beaverfoot. From the Stoddart 
Creek and Fairmont Springs sections in Windermere district; at 163 feet 
above the base of the Beaverfoot near the head of Windermere creek 
in the Stanford range; at Harrogate; and at Palliser pass, Rocky 
mountains, British Columbia. 
Streptelasma distinctum n. sp. 
Plate I, figures 6, 7 
Corallum simple, enlarging rapidly, not complete in any specimen, 
the largest being about 1§ inches in length. Epitheca somewhat wrinkled, 
showing the vert cal striation of the septa. On the exterior surface there 
is a slight angle, rather rounded, along the edge of the cardinal septum, 
in some cases giving the cross-section a semi-rhomboid form, the subdued 
angles being at the ends of the alar septa, at the cardinal angle and opposite. 
The short diameter passes through the cardinal septum. Some specimens 
appear to be almost straight, but a few show a slight tendency to curve 
away from the cardinal angle. Cup at least two-thirds length of whole 
height, bottom convex when seen in section. Septa primary and secondary, 
the latter in some cases becoming amalgamated with one another and the 
primary septa, forming a complete inner wall beyond which they do not 
project, the primary septa thirty to forty in number extending to the 
centre where they are somewhat twisted. 
