SPONGES OF BEAUFORT (N. C.) HARBOR AND VICINITY. 139 
Topsent (1889; 1900, pp. 34, 55) has concluded that there is no valid reason for 
maintaining the American form (Spongia sulphurea Desor) as a species distinct from 
C. celata. ‘This, in fact, seems to be the case, although a careful and detailed compari- 
son of specimens from the two sides of the Atlantic would in all probability show certain 
constant, if minute, differences. The Beaufort specimens examined do differ from the 
European individuals (comp. Topsent, 1900) in the following points: (1) The inhalent 
papilla are tubular except at the very top, where the trabecule which pass out from the 
wall to support the pore membrane encroach upon the axial cavity. In the European 
sponges (Topsent, loc. cit., pp. 35, 47) these papill are filled with tissue except basally, 
where they are hollow. (2) In the Beaufort specimens the head of the tylostyle only 
rarely exhibits a distinct apical prolongation, whereas this is the rule in the European 
sponges (Topsent). 
Topsent (loc. cit.) gives the range in size of the tylostyles as 180 to 360 4 by 3 tog. 
The range in size for the Beaufort specimens is close to this. Moreover, the shape of the 
spicules is the same, except for the above-mentioned detail, in the two sets of specimens. 
In the European sponges this is the only spicule that usually occurs. In very young 
specimens, chiefly in the papille, Topsent finds, however, spinose spirasters. But . 
these spicules soon cease to be formed. No such very young specimens have been 
studied on this side of the Atlantic. In some European individuals of this species 
long, slender, smooth oxeas, generally in fascicles, occur. Sollas has grouped these as 
var. linearis, but Topsent thinks the point is only a character such as separates indi- 
viduals and is not the mark of a subgroup. 
Poterion Schlegel. 
Beginning as a boring sponge, the body becomes free, large, and vase-shaped, with 
the incurrent apertures on the outer surface and the excurrent apertures on the inner 
or cloacal surface. Skeleton made up of tylostyles. 
Poterion atlantica,n.sp. (Pl. LVI, fig. 1; Pl. LXVI, fig. 5ra, }, c.) 
A single specimen was trawled by the Fish Hawk on the “Fishing Bank’’ off Beaufort Inlet at a 
depth of 14.5 fathoms. 
The sponge is vasiform, about 12 centimeters across at the top. The vasiform cavity extends 
entirely through the sponge, which, however, has had its base torn off. Actual height of the specimen 
is 11 centimeters. The height of the uninjured sponge was probably considerably greater. 
The outer surface exhibits contiguous, or nearly contiguous, circular, or irregularly rounded areas 
about 5 millimeters in diameter. These in the preserved specimen are slightly depressed. The central 
and greater part of each area is porous and recticular, as seen with the lens and even with the eye, this 
part measuring about 3 millimeters in diameter. These are the pore areas. Micropscopic preparations 
of the surface and sections through the pore areas show that each area includes numerous pores 75 to 100 
in diameter. From each pore a canal of about the same diameter passes vertically into the cortex. The 
inner surface exhibits similar areas, the center of each occupied by an osculum o.5 to 1.0 millimeter in 
diameter. The osculum is the aperture of an oscular (chonal) canal which passes vertically through the 
cortex. 
The sponge has a gray, dense, cartilaginous cortex both on the outer and inner surface of the cup. 
The surface is now (in the preserved specimen), blackish brown, interior yellow. The interior looks 
fibrous and is comparatively solid. 
Spicules (P1. LXVI, fig. 51a, 5, c)—Smooth, slightly curved tylostyles, 210 to 460uby 4to8u. The 
head of the spicule may be globular (fig. 515), or there may be a slight constriction around it (fig. 51a), 
or the enlargement may be located a slight distance from the end (fig. 51c). There are no microscleres. 
