FROM A DREDGING IN THE WEDDELL SEA. 
693 
the wall with the stirrup-pores has also the larger apertures, I incline to regard it 
as the inner, and that with the small pores as the outer. As mentioned above, no 
complete cups have been obtained, but the fragments exceed in length any other 
form present in the material. Even if the broken specimen of fig. 27 had been 
complete, it would have constituted the largest specimen in the whole of this 
collection. 
The species may be described as follows : — Walls folded gently ; inter vallum 
narrow (‘5 mm.). Outer wall simple, porous, pores 8 per mm. Inner wall simple, 
pores 6 per mm., “ stirrup ’’-pores on inner ends of septa. Septa imperforate except 
for stirrup-pores. 
Spirocyathidse. 
Spirocyathtjs, Hinde, 1889.* 
Spirocyathus atlanticus (Billings, sp.). 
1861. Archseocyatlius atlanticus, Billings, Lower • Sil. Fossils, p. 4, figs. 1-3. 
1865. „ ,, „ Palse. Fossils, vol. i, p. 5, fig. 5. 
1880. ,, „ Roemer, Letheea Geognostica. 
1886. „ „ Walcott, Bull. No. 30, U.S. Geol. Surv., p. 75. 
1889. Spirocyathus „ Hinde, Q.J.G.S., vol. xlv, p. 136, pi. v, figs. 8-10, 
1889. „ ,, Walcott, 10 if A Annual Report, U.S. Geol. Survey. 
1899. ,, sp., Yon Toll, “Sibir. Camb.,” Mem. Acad. Imp. des Sc. Petrograd, ser, viii, vol. viii, 
p. 45, pi. vi, fig. 8. 
1910. ,, radiatus Taylor, Mem. Roy. Soc. S. Australia, vol. xi, part ii, p. 147, text-fig. 35. 
1910. „ irregularis, Taylor, Mem. Roy. Soc. S. Australia, pp. 148, 149, pi. xvi, figs. 93, 94. 
Two examples of the above form were discovered in the material, and each was 
about 20 mm. in length. A transverse section, fairly high in the cup, is given in 
PI. Ill, fig. 32, and it compares well with the figures of the type specimen as given 
by Hinde. As in that specimen, the skeletal structures have been thickened by a 
coating of material, and the appearance is analogous to that produced on the septa 
of many rugose corals (cf. Aulophyllum) by “ callus” growth. But the chief points 
of interest in these new specimens lie in the nature of the fixing organs or processes, 
and in the apparent similarity to the genus Protopharetra which is shown by the 
lower parts of the cup. 
A cross-section at a lower level in the skeleton is shown in PI. IV, fig. 39, and 
the whole is very suggestive of a section from a Protopharetra type. In this 
connection it is interesting to recall Hinde’s words when describing the new genus 
Spirocyathus. He notes that he has “ considerable difficulty in determining whether 
Spirocyathus could be established as a genus distinct from Protopharetra .” t 
Bornemann, in erecting the new genus Protopharetra, considered that it was not 
an independent type, but merely the lower part or rooting part of other forms of 
* Hinde, Q.J.G.S., vol. xlv, 1889. 
t Hinde, loc. cit., p. 138, footnote. 
