18 
Diphyphyllum (?) 
The two following species, though differing in several respects from the 
typical Diphyphyllum , are provisionally referred to it. The external 
characteristics and mode of growth are similar to that genus. The typical 
Diphyphyllum has an outer vesicular zone and an inner zone characterized 
by well-developed tabulse. The two Rocky Mountain species appear to 
have a thick wall. If there is a finely vesicular area just within the outer 
wall the form of preservation has obliterated it, thickening the wall. Both 
species have long septa extending to the centre, a feature which is seen 
in several species of Diphyphyllum; the smaller does not perserve any other 
development in the inner side of the corallite, the larger shows the vesicular 
plates persisting into the interior part of the corallite, the resulting cell 
spaces being . coarser than is usual for the outer area of Diphyphyllum , 
a condition similar to that described in D. huronicum. It is possible that 
these differences are of generic value, but if so, better material would be 
required to warrant separation from DiphyphyUum , so that pending the 
discovery of more and better specimens the species are here referred to 
that genus. 
Diphyphyllum ? halysitoides n. sp. 
Plate II, figures 8, 9 
There is no specimen sufficiently well preserved to show the marginal 
area of the corallite. There are, however, several characteristics which 
are very evident. Corallum apparently massive. A weathered longi- 
tudinal section shows that the corallites increase by lateral budding. 
Tubes mostly circular, though some are oval; free, or in many cases just 
touching one another, forming a chain of coarse reticulations suggestive 
of a very large species of Halysites. Diameter of corallites 3 mm. to 5 mm. 
Septa, about forty in number, primary and secondary, the former very fine, 
reaching nearly to the centre. One corallite which is preserved almost 
to the centre shows a tendency for the gathered ends of the septa to make 
a very slight twist. Tabulse not preserved. 
DJ halysitoides can easily be distinguished from any other species 
of this genus by its form of growth. 
Horizon and Locality . Richmond: Beaverfoot. Twenty feet up in 
the light grey Halysites beds, Beaverfoot range, northeast of mount 
McMurdo, near Golden, and from Harrogate, B.C. 
Diphyphyllum ? primum n. sp. 
Plate II, figure 10 
Corallites larger than in the preceding species, circular, diameter 
from 3? mm. to 6 mm. Some contiguous, mostly separate, but irre- 
gularly connected at intervals by the prolongation of the rugose growth 
wrinkles. Increase often by lateral germination, the new corallites enlarging 
rapidly, but in many cases a number will arise from the side of a tube 
horizontal to their direction, very similar to the stolon root form in plants. 
