442 
tube should, I think, more easily be produced, than a new type 
of aster, involving a lesser alteration of the genotypical construc- 
tion; at least it seems that the cloacal tube may be an answer 
to environmental influence while we can hardly imagine envi 
ronmental influences to alter the asters; consequently an alteration 
of the asters must evidently be due to a higher degree of germinal 
variation than the production of the cloacal tube. 
Monosyringa Mortenseni nov. spec. 
(Fig. 4 a-g.) 
10 miles N.W. of Cape Maria van Diemen. 50 fathoms. Hard 
bottom, 5/1.1915. One specimen, but only the cloacal tube, 30 mm 
long, 3 mm thick. Three Kings, 65 fathoms, hard bottom, 5/1.1915. 
One specimen, likewise only the cloacal tube. Colville Channel, 
35 fathoms, sand and mud, 5/1.1915. One beautiful specimen. 
The body is spherical, 20 mm in diameter; the surface of the 
body is completely covered with sand, fragments of shells, etc.; 
the sandgrains can only with difficulty be removed from the sponge; 
where they have been there are seen small corresponding hollows 
in the surface of the sponge; other orifices than those at the top 
of the cloacal tube could not be detected; the cloacal tube is di- 
stinctly set off from the main body; it is completely free from 
foreign particles at the surface, white of colour, cylindrical, curved, 
ca. 30 mm long, 4.5 mm in diameter; the outermost part of the 
tube in all three specimens is, unfortunately, damaged, perhaps torn 
off. Consistence hard. 
The skeleton of the body is distinctly radially arranged; it con- 
sists of long spicula-fibres running from the center of the sponge 
to the surface, projecting a little beyond this; the fibres are com- 
posed of oxea and orthotriaenes, the latter mainly restricted to the 
outermost part of the fibres; there is a distinet fibrous cortex, 
about 0 , 5 —1 mm thick, and of a somewhat bluish colour, resemb- 
ling porcelain; all the sponge-tissues are crowded with microscleres; 
in the cortex the asters and trichodragmata are often lying in de- 
finite strands; both forms of microscleres, especially the tricho- 
1) Perhaps even many tetraxonoid sponges may be able to produce such a 
tube when covered by sediments, which has evidently been the case 
with the specimens found of the three mentioned genera. 
