Occurrence of Sponges in an Aquarium 
M. W. DE Laubenfels^ 
On October 6, 1947, nine species of sponge 
were found growing in one of the tanks of the 
Honolulu Aquarium. Two of these prove to 
be as yet undescribed. 
According to information furnished by Mr. 
Spencer Tinker, the director of the aquarium, 
none of these sponges were brought to the 
tank as adults. Most or all of them must have 
reached it as larvae in the running sea-water 
circulation. Some may have come as minute 
juveniles attached to marine objects which 
were placed in the aquarium. 
It is curious to note that this astonishing 
abundance of sponges occurred in only one 
of the many tanks of the aquarium. It ap- 
peared desirable to make a continuing study 
of this phenomenon, and instructions were 
left for careful preservation of it, but a few 
days later an attendant meticulously destroyed 
every bit of this sponge population. 
Study of sponges in the tanks of the Hono- 
lulu Aquarium was then continued for 3 years. 
For 12 months of the year, with some seasonal 
fluctuation in size, one might find a few small 
Tethya and an occasional encrusting sponge 
in the many tanks, but the sponges were 
consistently too small and juvenile for iden- 
tification. 
This latter situation is in harmony with the 
usual extreme scarcity of "volunteer” sponges 
in aquariums. 
The nine species may be described as 
follows : 
Haliclona permollis 
(Bowerbank) de Laubenfels 
This species was represented by thin, trans- 
lucent incrustations with lumpy or slightly 
conulose surface. Some were nearly colorless; 
one was bright violet, the typical color of this 
species. Many of the volunteers observed sub- 
sequent to October, 1947, may have been of 
this sort. It is described in Pacific Science 
(de Laubenfels, 1951: 258) from specimens 
taken elsewhere in Hawaii. It is an abundant 
species of world-wide distribution. 
Adocia gellindra de Laubenfels 
This species was described (de Laubenfels, 
1932: 114) from California and not recorded 
again until now. It is rather close to the wide- 
spread species Adocia cinerea (Grant), but its 
spicules are smaller than those of cinerea. In 
the Honolulu Aquarium it was represented by 
a single pale crust on a rock; it may have been 
fetched from the ocean along with that rock, 
but the rocks so brought in were so roughly 
treated, often out of water entirely, that this 
origin is not certain. In fact, it is more prob- 
able that this species is also a volunteer. 
^ Department of Zoology, Oregon State College, 
Corvallis, Oregon. Manuscript received June 25, 1953. 
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