SPONGES OF BEAUFORT (N. C.) HARBOR AND VICINITY. 163 
some of the peculiarities of the skeletal framework which Vosmaer has brought out in 
his stimulating paper are such as distinguish species rather than genera. 
In listing the sponge under Acanthella we rely for the present on the assumption that 
the cartilaginous consistency, and especially the aculeate surface, when coupled with a 
lamellate form and the general type of Axinellid skeleton, are signs of kinship. 
Species of Acanthella, in the usual sense, are known from the Red Sea: A. aurantiaca 
Keller (Keller, 1889-91; Topsent, 19066; Row, 1911); Mediterranean: A. acuta Schmidt, 
A. obtusa Schmidt (O. Schmidt, 1862; Topsent, 1901a); Australian waters: A. stipitata 
Carter, A. fenuispiculata Dendy (Dendy, 1896); Gulf of Manaar: A. carteri Dendy, A. 
flabelliformis Keller (Dendy, 1905); Torres Straits: A. pulcherryma Ridley (Ridley, 1884; 
Ridley and Dendy, 1887); Aru and Kei Islands: A. euctimena Hentschel, A. sp. Hent- 
schel (Hentschel, 1912). 
It would seem that Acanthella flourishes in warm waters, although Vosmaer some 
time ago (1885) referred a sponge taken in the Arctic Ocean, A. multiformis, to this 
genus. 
KERATOSA. 
Family DARWINELLIDA (APLYSILLIDZ: auct.). 
Keratosa with eurypylous and large flagellated chambers; with a skeleton com- 
posed of separate horny fibers that ascend from the base of the sponge and are simple 
or branched, or the skeleton may be reticulate; spicules of spongin may also occur; the 
spongin fibers contain a medulla or pith and lack foreign mineral particles. 
Aplysilla F. E. Schulze. 
Incrusting or lamellar forms; skeleton nonreticulate, composed of separate fibers; 
without spongin spicules. 
Aplysilla longispina, n. sp. (Pl. LXIV, fig. 42; Pl. LXV, figs. 45, 48; Pl. LXVI, fig. 64a, 6, c, d.) 
One large, incrusting specimen taken on the piles of the Morehead railroad pier, near the town 
end, just below low-water mark. 
Sponge (Pl. LXIV, fig. 42) 1 to 20 millimeters thick, covering an area 150 millimeters in diameter, 
apparently with unlimited lateral growth. The surface is covered with numerous slender, sharp conuli 
several millimeters high (the range is 1 to 5 millimeters, the common height about 3 millimeters) and 
a variable distance apart (often about 3 to 5 millimeters), frequently but not always connected by thin, 
sharp-edged ridges or folds. Conuli in general simple, but not uncommonly bifid or trifid at the apex. 
Surface very uneven because of numerous ascending portions, all of which are low, irregular, and so 
vaguely delimited as not to merit the name of lobes. A few oscula, 1 to 3 millimeters in diameter, are 
scattered over the surface. 
Color, sulphur yellow, turning instantly in alcohol to an indigo blue. Sponge soft and elastic; 
interior cavernous (Pl. LXV, fig. 45). 
The skeletal fibers are simple, or branched somewhat in elk-horn fashion (Pl. LXVI, fig. 64a, b,c). 
At the under surface of sponge they expand into thin, basal, horny plates, which sometimes, at any 
rate, connect with one another. ‘The fibers extend vertically upward into the conuli, reaching the apex 
of the latter (Pl. LXV, fig. 45). The simple fibers support each a single conulus, and each terminal 
division of a branched fiber supports a conulus or one of the subdivisions of a primary conulus. The 
more complex fibers thus support a number of conuli. 
The fibers measure 100,to 250 w in diameter just above the basal plate and 15 to 30 u near the tip. 
The pith, which consists of successive thimble-shaped segments of varying length, forms about half of 
the fiber in the basal portion. The spongin wall is clearly stratified (Pl. LXVI, fig. 64d). The fibers are 
generally smooth and have no inclusions, but occasionally foreign bodies are found in them. 
