492 PKOF. A. DENDY AND MISS L. M. FREDERICK ON 
Spicules : — (1) Orthotrisenes ; shaft straight, gradually pointed^ measur- 
ing about I'l by O'OIS mm. ; the cladi, which are about 0'3 mm. long, at 
first form with the shaft an angle of about 120°, but somewhere along their 
length they abruptly turn back so that their distal ends are at right angles to 
the shaft. 
(2) Anatrisenes ; shaft straight, gradually tapering to a sharp point, 
measuring about 1"1 by 0'03 mm. ; the sharply-pointed cladi, which are 
about 0'15 mm. long, curve outwards almost at right angles to the shaft and 
then run back parallel to it. 
Our specimen contains only a few of the irregular orthotritenes and of the 
sigma-like anatriasnes figured by Lendenfeld in his ' Valdivia ' report. 
(3) Oxea ; straight or slightly curved, bluntly pointed, measuring about 
1-1 by 0-015 mm. 
(4) Oxj'asters ; of two kinds — -{a) large, with 2 to 6 fairly stout, roughened, 
blitntly pointed rays, total diameter about 0'02 mm.; these are most abun- 
dant just beneath the inhalant chones : (b) small, with 6 to 10 thin, very 
minutely roughened rays; total diameter 0'014 mm. These are scattered 
through the choanosome, but not abundantly. 
Previously known Distribution. Dirk Hartog, W. Atistralia (Lendenfeld). 
Register Nos. and Localities. IV. 8, Wooded Isle ; VI. 18 c, Sandy Isle. 
16. Ancorina AUSTRALiENSis {Carter). (PI. 25. fig. 11.) 
Stelletta australiensis Carter [1883]. 
Ecioneina australiense SoUas [1888]. 
Ancorina anUraliensis Lendenfeld [1903]. 
There are four specimens in the collection. The largest (R.N. VI. 6 a ; 
PI. 25. fig. 11) forms an incomplete eone, 40 mm. in height, with a base 
measuring 60 by 70 mm. ; the apex is truncated, and over the flattened area 
thus formed, which measures 40 by 25 mm., are scattered numerous open 
vents which vary in diameter from 0'25 to 1 mm. Part of the side of the 
cone is encrusted by Spongelia dakini n. sp. The second specimen (R.N. I. 3) 
is irregularly massive and measures 80 by 60 by 50 mm. ; its upper surface 
is almost entirely covered by an encrusting Reniera and a mass of other 
debris. The third specimen (R.N. II. 6) measures 40 by 45 by 25 mm., and 
is largely overgrown by a mass of other organisms. The fourth (R.N. III. G) 
an irregular, cake-shaped mass, measures 85 by 50 by 40 mm.; its upper 
surface is uneven and slightly wrinkled. 
No vents are visible except in the figured specimen ; inhalant pores, 
visible with a pocket lens, are scattered in groups of two or three over the 
smooth upper surface of all the specimens ; they are most marked in the 
figured specimen. Colour in spirit purplish brown on outside, light yellowish 
brown inside ; texture firm and compact. 
The skeleton consists of radially arranged trisenes and oxea, with a layer 
of small ectosonial oxea vertical to the surface. The microrhabds are 
