264 
thick. In life it was white; the consistency was 
extremely slimy but, at the same time, sticky 
or glue-like. The surface is smooth and 
lipostomous. 
The ectosome is not sharply set off from 
the endosome. The latter is microcavernous 
with some vague tracts, about 100 to 125 m 
apart and 20 fi in diameter, and containing 3 
to 10 spicules per transverse section. 
The skeleton, other than the ubiquitous 
colloidal stuff, consists of spicules which may 
be regarded as comprising only a single cate- 
gory but with much individual variation. 
Some are simple, smooth, sharply pointed 
oxeas 4 by 112 )U. Others, probably juvenile, 
are as small as 1 by 85 m- Many are as large as 
from 5 by 117 to 6 by 150 ju, and the larger 
ones frequently have unusual shapes. It is 
common for them to be centrotylote, and 
some are also strongylote. Many, not centro- 
tylote, have two distinct angular bends near 
the mid-point. 
I 1 I I I I I I I I I 
Fig. 12. Khaphisia myxa: spicules, from camera lucida 
drawings. (The scale shows 100 microns by tens.) 
All the sponges now in Rhaphisia, except 
the genotype, have much larger spicules than 
those of this new species. The genotype is 
Khaphisia laxa Topsent (1892: xvii) from the 
Mediterranean region and is clearly the 
closest relative to the Hawaiian form. It also 
was viscous, but lacked the peculiar spicule 
shapes of myxa. 
The species name here selected is derived 
from the Greek for slimy, and refers to the 
extreme development of a viscous colloid by 
this species. 
PACIFIC SCIENCE, Vol. V, July, 1951 
Spirastrella keaukaha new species 
Fig. 13 
The type specimen of this species is U. S. 
National Museum, Register Number 22777 
(My No. H. 78), collected at Keaukaha, 
May 15, 1948, far back from the surf on vol- 
canic rock barely below low tide. This species 
was found also at Kaalualu and at Honaunau 
and is abundant all around Hawaii. 
This is an incrusting species often as much 
as 3 mm. thick, spreading laterally in- 
definitely. In life it was orange-brown to red- 
brown, with a paler interior, but often with a 
very dark layer about 0.6 to 1 mm. below the 
surface — a layer about 50 to 120 p. thick. The 
consistency was rather like that of cheese. 
The surface is smooth and lipostomous, but 
subdermal canals (which doubtless terminated 
at oscules which close quickly and readily) are 
easily visible. 
The ectosome is characterized by greater 
density and pigmentation than the micro- 
cavernous endosome. The microscleres are 
exceedingly abundant in the dermal layer. 
Fig. 13. Spirastrella keaukaha; spicules, from camera 
lucida drawings. A, Tylostyle; B, larger spiraster; 
C, smaller spiraster. (The scale shows 100 microns by 
tens.) 
The skeleton is composed of tylostyles and 
spirasters. The former are smooth and straight, 
8 by 328 p., usually in confusion but oftenest 
with points directed toward the surface of the 
sponge. The microscleres are of two size 
ranges. The larger spirasters are about 40 p 
long, the smaller about 16 p long. Both kinds 
are astonishingly nearly straight, only slightly 
spiral. The smaller variety has spines which 
are more obtuse than might be expected. 
