Aquarium Sponges — DE Laubenfels 
339 
Fig. 2. Spicules of Kotimea tethya, camera lucida 
drawing. A, Style, X 180, B, spherasters, X 780. 
diate. Even when juvenile, specimens of Tethya 
are globular and rough, often already showing 
the tuberculate surface that is so characteristic 
of the adults. Many sponge species have ju- 
venile incrusting stages, but not so Tethya. 
Lest one assume that the specimen now 
under discussion might be a Tethya profound- 
ly modified by the artificial environment, it 
may be pointed out that Tethya diploderma is 
the commonest volunteer sponge in the Ho- 
nolulu Aquarium, one that continued to be 
found throughout subsequent years. In the 
same aquarium with this Kotimea on October 
6, 1947 , there were numerous specimens of 
Tethya, some obviously very young, others 
older and larger. All were typical, with globu- 
lar shape, pronounced cortex, and radiate in- 
ternal structure. 
There are two other species already in the 
genus Kotimea. The type is moorei, described 
as Hymedesmia moorei by Carter (1880: 472) 
from Ceylon. Its microscleres were much like 
those of Tethya. Its megascleres were about 
as long, but were twice as thick, and some 
were tylostyles. This latter difference is here 
regarded as significant. The other species was 
described as Hymeraphia spiniglohata by Carter 
(1879: 301 ) from the South Pacific. It had 
only tylostyles and only the largest sort of 
spheraster. 
The species name selected calls attention 
to the resemblance to Tethya. 
Terpios zeteki de Laubenfels 
This species was first described from the 
Pacific coast of Panama (de Laubenfels, 1936: 
450 ). It is abundant in Hawaii and therefore 
was redescribed (de Laubenfels, 1950: 28). 
This species is regularly yellowish as to 
endosome, but its exterior is in some spec- 
imens blue, in others red. The specimen in 
the Honolulu Aquarium was incrusting, with 
the normal endosome and a crimson-red 
ectosome. 
Tethya diploderma Schmidt 
This world-wide species is common in Ha- 
waii and, as already noted, even regularly 
invades the Honolulu Aquarium tanks. In the 
tank now under discussion there were nearly 
a score of specimens of Tethya, well distrib- 
uted about the walls, bottom, and loose rocks. 
This species was redescribed (de Lauben- 
fels, 1950: 30). 
Oscarella tenuis Hentschel 
This species was described by Hentschel 
( 1909 : 351 ) from Australian waters; this is 
its next recorded occurrence. In the Honolulu 
Aquarium it was represented by a single, 
opaque, whitish incrustation on the concrete 
wall, paper-thin and about 3 centimeters in 
diameter. Its flagellate chambers were 30 mi- 
crons in diameter. 
This genus .has no mineral or spongin skele- 
ton, consisting only of the protoplasmic 
structures and some inanimate colloidal stuff. 
It is doubtless much more abundant than 
the few records would seem to indicate but is 
ordinarily overlooked. Even when noticed, it 
is usually hopelessly ruined in the process 
of scraping it off rock or coral, so that the 
necessary histological study becomes im- 
possible. 
Leucosolenia eleanor Urban 
This species is abundant along the west 
coast of the United States; this is its first 
record from elsewhere. 
This is a calcisponge of the simplest, or 
Ascon, type. The Ascon tubes are long, how- 
ever, with many branches and anastomoses, 
so that a clathrous structure results. 
