198 
ZOOLOCxY OF THE FAR EAvST. 
The skeletons of the different specimens exhibit the same variation as has been 
noted in specimens from other locahties. In one from Madras, which was preserved 
with great care so as to avoid all pressure, the skeleton, as in Schmidt's original 
specimens, forms an irregular network of single spicules. On the external surface 
single spicules also project outwards from the nodes of this network. In examples 
from Bombay, on the other hand , longitudinal spicule-fibres 4 or even 6 spicules thick 
are well developed. In the Perak specimens the condition is intermediate, for the 
longitudinal fibres, though they can be detected, are not at all well defined and have 
not more than 3 spicules abreast. 
Of all known sponges Reniera implexa has one of the greatest, if not the greatest 
of bathymetric ranges. It has been found in shallow water in the Adriatic and on the 
coasts of India and Ceylon, at various depths, aU considerable, up to 450 fathoms in 
the Atlantic, and now between tide- marks in the Straits of Malacca. Differences in 
size of spicules or in skeleton-structure are not correlated with depth of habitat, but 
it is probable that an upright growth is maintained only in very still water. 
Family AXINELLIDAE. 
Amorphinopsis excavans, Carter. 
1915. Amorphinopsis excavans. Annandale, Rec. Ind. Mits. XI, pp. 467-470, figs. 4, 5. 
I have redescribed this species, with a new variety, in the paper cited. Here I 
have to describe a second new variety. 
var. robinsonii, var. nov. 
(Plate II, fig. 3 ; plate IX, fig. i.) 
The sponge formed a layer about 5 mm. thick and of considerable area. It had 
a greenish-grey colour when alive and is grey in spirit. It is tough and rather elastic, 
not very hard. The surface is uneven, covered with a network of low ridges which 
often bear at the nodes short upright conical projections not more than 3 mm. high. 
These projections have a hirsute appearance under a hand lens. No orifices are appa- 
rent in the preserved sponge but the whole structure is pierced by a number of oval 
gaps of relatively large size. These, however, are not natural to the sponge but 
covered the burrows of bivalve molluscs burrowing in the wood to which it was 
attached. 
In internal structure the sponge closely resembles the typical A. excavans [op. 
cit., 1915). The upright spicule-fibres are well defined and below the external surface 
are splayed out as .shown in fig. i on pi. IX. There is also an irregular skeletal reticula- 
tion of spicules of various forms and sizes and a distinct external layer of small 
spicules arranged horizontally in the ectosome. The conical projections on the surface 
apparently represent conuli in which the orifices are closed by contraction. Large 
horizontal channels with a circular or horizontally oval cross-section run through the 
substance of the sponge, especially in the region immediately below the ectosome. 
There is a stout horny basal membrane. 
The normal spicules are of three types and each type is represented among those 
