696 
DR W. T. GORDON ON CAMBRIAN ORGANIC REMAINS 
with one of Bornemann’s figured types (Taf. vi, figs. 3 and 4). The vertical character 
of the irregular septal plates is specially evident towards the base, where the section 
is more tangential. In transverse section the septa are seen to form an irregular 
meshwork (PI. VI, fig. 65), which is crossed by delicate curved plates forming 
dissepimental tissue. The outer wall is well marked, as also is the inner. The septa 
are plates with irregular vertical corrugations which form a series of inosculating 
partitions between the two walls. Irregular emergencies near the base appear 
to have fixed the whole cup (PI. VI, fig. 66). A closer examination of the inner 
wall (fig. 65) shows that between the main septal plates small projections stretch 
into the intervallum, so that the inner wall becomes very conspicuous. In PI. Ill, 
fig. 36, an enlarged view of the cup of PI. VI, fig. 66, is given, and the inner wall 
is now seen to be porous. These pores (p) are small, probably 3 or 4 to the 
intersept, and this accounts for the presence, in transverse section, of the small 
structures between adjacent septa. They are really the divisions between the 
pores. But this figure illustrates another feature — -the central cavity is filled 
by oblique cross partitions ( Boden of Bornemann) between which numerous 
waved, vertical rods are clearly visible. Both the tabulae and the rods are out- 
growths from the walls, and the whole completely fills in the central space. It 
would be difficult, however, to call this a coralloidal growth such as has been noted 
in Thalamocyatlius trachealis, Taylor, sp. 
Protopharetra radiata, Bornemann. 
1886. Protopharetra radiata , Bornemann, “ Yerstein. Sardinien,” Nova Acta der Ksl. Leop.-Carol. Deut. 
Akad. der Nat., vol. li, p. 48, Taf. vii. 
Several specimens of a rather larger form belong to this second species. The 
largest cup was 1 cm. in diameter, and indeed it was the largest complete cup 
obtained from the material. It is represented in PI. Ill, fig. 35, and illustrates 
most of the features already described in P. polymorpha. The septa show a 
certain amount of thickening, and there is no sign of infilling material in the cup. 
Another specimen (PI. VII, fig. 72) presents a good example of the branching 
in this species. The lowest section shows two cups joined together. Of these, 
one, a, has a clearly marked inner wall and the central cavity crossed by two 
tabulae, while the ends of a few vertical rods are also visible. The central cavity 
of the second cup, b, is more completely filled, and consequently the inner wall 
is not so prominent. In the succeeding section (fig. 73) a has disappeared, b is 
cut at a higher level, and a third cup, c, with rooting process r, has joined itself to 
b. In the third section (fig. 74) c is cut at a higher level (very similar to that 
of a, fig. 72) and b has now disappeared. At d and e, however, sections of the 
presumed fixing strands are evident. The only distinction between P. polymorpha 
and P. radiata is one of size, the latter being larger in every way. 
