SPONGES FROM THE ABKOLHOS ISLANDS. 505 
the pore-areas. The sieve-membrane of these areas is free from spicules, 
except for numerous isochelse. 
Spicules : — (1) Tornotoxea (PL 26. fig. 13 a) ; smooth, slender, usually 
straight ; ends hastate but unequal ; size about 0"4 by 0'006 mm. 
(2) Acanthostyli of two kinds — (a) (Pi. 26. fig. 13ft) with short, straight 
or sotnetiraes slightly curved sliaft, which is slightly swollen at one end and 
sharply pointed at the other, covered with small, slightly recurved spines ; 
size about 0-14 by 0-013 mm. : (6) (PI. 26, fig. 13 c) with long, slightly 
curved shaft, the curve being most noticeable just above the slightly swollen 
base ; the spines are very small and only extend for about two-thirds of the 
shaft from the base, thus leaving the sharply-pointed apical end quite smooth. 
These longer acauthostyles, which measure about 0'35 by O'Ol mm., are found 
only in the larger s|)ecimen (R.N. VI. 4). 
(3) Tridentate isochelse (chelae arcuatse) (PI. 26. fig. Vid), with stout, 
slightly curved shaft and short teeth ; measuring about 0*024 mm. in length. 
These spicules are very abundant in the dermal membrane, especially in 
the pore-areas, but occur also scattered through the choanosome. 
This species agrees very closely with the European Anc/dnoe fictitius 
(Bowerbank) J. Stephens [1921] as regards its pore-areas and spiculation, 
but differs widely in its mode of growth, which closely resembles that of 
Yvesia [Grayella) spinulata Hentschel [1911], also a S.W. Australian 
and Indian Ocean species (vide Dendy [1921 A]). Indeed, Yvesia spinulata 
differs from Atichinoe /ictitioides in little if anything- more than the replace- 
ment of the acanthostyles by acanthoxea, and may probably be regarded as a 
direct derivative of the latter species. 
Register Nos. and Locality. VI. 4, VI. 11, Sandy Isle. 
38. Dendokicella schmidti [Ridley). 
Crella schmidti Ridley [1884]. 
Damiria australieitsis Dendj [1896]. 
Damii'ia Schmidti Tnpsent [1897]. 
Damiria australiensis Lindgren [1897, 1898]. 
Dendoricella Schmidti Hentschel [1911, 1912 A]. 
The larger of the two specimens (R.N. IV. 9) in the collection consists of 
five erect, digitiform processes springing from a thin, common base ; the 
processes measure about 8 mm. in diameter, and four of them divide at their 
ends into a varying number of slender, secondary, digitiform processes. The 
second specimen (R.N. III. 10) consists of a portion of a single lobe, dividing 
above into four slender, digitiform processes. The general surface of the 
sponge is covered with narrow, meandering ridges running longitudinally ; 
the dermal membrane, which is smooth and transparent, is interrupted by small 
pore-sieves, visible with a lens. A number of small oval vents, sometimes 
lying in slight depressions, are scattered singly on the processes. Colour in 
spirit light greyish brown ; texture very soft, spongy, friable. 
