128 
Sherriffs refers ten specimens to the Section Glomeratae and the species clavata 
(Kiikenthal), but a re-examination of them and a number of others in the collection has led us 
to the conclusion that, although they agree with Kukenthal’s description to a certain extent, 
they are really Umbellate and belong to the spinu losa-gr oup. There are marked differences 
from the species described in that group which justify us in making a new species. For example, 
(i) the polyp stalk is much longer, (2) the supporting bundle is much less strongly developed, 
(3) the points consist of about six and certainly never more than eight double rows, and (4) 
the spicules of the sterile stalk are very characteristic, even diagnostic. They consist of irregular 
multiradiates, suggestive of actively moving amoebae, and similar forms with a distinct median 
constriction. Hence the specific name. 
Diagnosis: Umbellate; polyps in dense groups at the ends of the terminal branches ; 
polyp stalks very long ; supporting bundle weak; point spicules 6—8 pairs ; Grade II ; spicules 
of the sterile stalk: (1) irregular multiradiates suggestive of actively moving amoebae-, (2) similar 
forms with a distinct median constriction and (3) capstan-like bodies. 
Anthocodial Grade and Formula : 
II = 6—8 p -fi- o Cr -}- weak S. B. 
Descriptive Notes: 
Colony as a whole. Seventeen specimens from Station 302 range from 1.5 cm. in height 
to 17 cm. The mode of growth in all the specimens is noteworthy. The relative proportion in 
the various parts is fairly constant. In the largest specimen, the basal part of the sterile stalk 
bears numerous stolons, and is 3.5 cm. long. It is markedly flattened (or collapsed) and is 
3.5 cm. in breadth. From this arises a hard densely spiculose collar 6 cm. across. Surmounting 
this is a long sterile stalk 6 cm. in length which gradually tapers to 1 cm. and then again expands 
to carry the true polyparium, which is v loosely glomerate and extremely soft and limp. In this 
(the largest) specimen two limp branches arise at the upper junction of the collar and stem. 
Branching. The polyparium is strongly branched. The main branches subdivide several 
times. All the branches are limp and in the preserved specimens collapsed. 
Colouring. The colour of the stalk and branches is a dirty white. The collar is a con¬ 
spicuous red with white anthocodiae. The stalks of the polyps in the polyparium contain numerous 
small red spicules, but the anthocodiae are white. 
Polyp stalks and their spicules. The length and the spiculation of the polyp stalks varies 
markedly in the collar and polyparium. In the collar they are very long, often 3 mm., and 
densely spiculose. In the polyparium they are much shorter and contain only a few red spicules. 
In this region the length seldom exceeds 1.5 mm. 
Polyps. The polyps are clustered in small umbels at the ends of the branches in the 
polyparium, and on offshoots from the foliaceous collar. 
Supporting bundle. In the polyparium the supporting bundle is weak and in many cases 
takes the form of a dorsal ridge or an ensheathing narrow triangle of 3 — 5 pairs; but in the 
foliaceous collar it is much stronger, with the uppermost one or two spindles projecting beyond 
the base of the anthocodia. 
Anthocodise. In the polyparium the armature consists of about six very indistinct double 
rows, and on the ventral surface the spicules of a row are reduced in number. In the foliaceous 
