473 
the way in which Tedanione has probably developed from Tedania, 
viz. by an invasion of dermal diactinal spicules into the main 
skeleton; of course also the reversed process may have taken 
place: the evolution of Tedania from Tedanione by a stronger 
development of monactinals in the main skeleton; but a comparison 
with other Desmacidonidae seems to prove the other way of evolution 
as the more probable, since the styli in the main skeleton every- 
where seem to be the more primitive State of things. 
Covnulum novae-zealandiae nov. spec. 
(Fig. 26 a—d.) 
10 miles N.W. of Cape Maria van Diemen. 50 fathoms. 5/1.1915. 
One large beautiful specimen, about 200 mm in largest dia¬ 
meter, formed as a somewhat oblong pillow; it is torn loose from the 
body of attachment. The sponge is covered with numerous fistulae 
up to 30 mm in length, by a thickness of ca. 4—8 mm at the base; 
the apex of these hollow whitish fistules 
is often swollen button-like. I have not 
been able to see any oscula. Colour 
(formaline) light grey with a reddish tint. 
The main skeleton is a stout reticu- 
lation of smooth spicular fibres up to 
1000 ^ thick, thus easily seen with the 
naked eye; the fibres are branching and 
irregularly interwoven, often 6—8 mm 
apart. Under the dermal-membrane the 
fibres are expanding fanwise. The dermal 
skeleton and the skeleton in the fistulae 
consist of a dense feltwork of interwoven 
tylota, all lying tangentially. 
Spicules. a. Megascleres. Tylota 
(fig. 26 a—c), siender, slightly but ir¬ 
regularly curved, with beautiful, oval 
heads,. sometimes somewhat narrow just 
beneath the head; up to 870 x 15 
b. Microscleres. Isochelae palmatae 
(fig. 26 d), siender, short alae and teeth, 
ca. 27 fi in length. 
O 
Fig. 26. Corniiluni novae-zea¬ 
landiae nov. spec. a~b. Tylote 
(b from fistulae). c. Pinds of 
Tylota. d. Palmate Isochele. 
