Sponges of Kaneohe Bay — DE LAUBENFELS 
violacea is derived from the violet hue of this 
sponge. 
Myxilla rosacea (Lieberkiihn) Schmidt 
Fig. 10 
This species is represented in the fauna of 
Hawaii by only two known specimens; both 
were collected at Moku O Loe in Kaneohe 
Bay. The first specimen was taken Septem- 
ber 10, 1947, at a depth of 1 or 2 meters, on 
pilings at the dock ( location 6, Fig. 2 ) . This 
is deposited in the U. S. National Museum, 
Register Number 22734. A second was 
found January 10, 1948, in the sluice-way 
from one of the small lagoons (location 4, 
Fig. 2). 
This sponge is massive. Our specimens arc 
each fist-size, but much of the bulk is due to 
contained lumps of dead coral. The color in 
life is bright orange-red, paler in the interior. 
The consistency is slightly spongy, not espe- 
cially remarkable. The surface is slightly and 
irregularly lumpy. There is a conspicuous 
translucent dermis pierced by microscopic 
contractile pores; through it the larger canals 
that lead into the sponge from the floor of 
the subdermal space are easily seen. These 
openings are about 0.3 mm. in diameter and 
1.2 mm. apart. The oscules are few and scat- 
tered, about 6 mm. in diameter, and closable 
by very thin membranes. 
The ectosome is packed with special 
dermal spicules arranged tangentially. The 
endosome is cavernous, "crumb of bread" 
type, with the skeleton in "log cabin" or mod- 
ified isodictyal arrangement about small gross 
chambers. 
The ectosomal spicules are smooth-shafted 
tornotes; their ends are just faintly micro- 
spined, their size about 3 by 160 g. The 
endosomal spicules are acanthostyles, 8 by 
140 g. The microscleres include anchorate 
isochelas, approaching the unguiferate type 
but only 15 g in total length, and also com- 
monplace sigmas, 18 to 30 g in chord length. 
17 
This species was first described from 
Europe, as Halichondria rosacea, by Lieber- 
kiihn (1859: 521). It was transferred to 
Myxilla (genotype) by Schmidt (1862: 71). 
It is abundant throughout Europe, on both 
the Mediterranean and Atlantic coasts, but 
appears to be absent from the Americas. 
The European specimens and these from 
Hawaii agree rather closely. The former have 
isochelas that are often nearly twice 
as large as those of the latter, but this is 
scarcely a specific difference in view of the 
other similarities. 
A 
Fig. 1 0. Myxilla rosacea, spicules, from a camera 
lucida drawing, X 444. A, dermal tornotes. B, en- 
dosomal acanthostyles. C, sigmas. D, anchorate 
isochelas. 
In reviewing the very numerous species of 
the genus Myxilla with a view to identifying 
the Hawaiian specimen, various items become 
noteworthy. The genus Burtonanchora de 
Laubenfels (1936: 94) was established for 
certain species formerly in Myxilla but differ- 
ing chiefly in that they have only smooth 
spicules, and thus passing over into the family 
Tedaniidae. Perplexing intermediate forms, 
having spicules that are only very slightly 
spined, exist; yet for convenience, if nothing 
else, the division is worth maintaining. The 
following additional species are now taken 
out of Myxilla to go into Burtonanchora: 
M. acrihria de Laubenfels, M. crihrigera Rid- 
ley and Dendy, M. mollis Ridley and Dendy, 
and M. novaezealandiae Dendy. Two species, 
D. inaequalis and D. simplex, first put in 
Dendoryx by Baer, are also placed in Burton- 
anchora. 
