SPONGES OF BEAUFORT (N. C.) HARBOR AND VICINITY. 151 
jecting lobes like those of the younger stages. A characteristic specimen (Pl. LXI, fig. 26) measured 
roo millimeters in its greatest diameter. Masses with diameter twice as great occur. 
Color white, frequently with a green or blue cast. Sponge comparatively firm and brittle, and 
generally dirty. It is much infested with worm tubes and overgrown with hydroids and polyzoa. 
Over the entire surface are numerous tubular translucent papillae (Pl. LXI, fig. 27), perforated by 
numerous pores. The papilla may be simple or branched, often bifurcated. They are contractile 
and may almost entirely disappear. 
Oscula 1 to 2 millimeters in diameter are scattered over the surface and often develop at or near 
the ends of lobes. The pores are distributed over the general dermal membrane and papille. Over 
the papillz they are abundant and in an alcoholic specimen measure about 20 » in diameter. In the 
same specimen the pores over the general surface are almost all closed. The few found open measure 
up to 100 w in diameter. The dermal membrane is translucent, showing anastomosing subdermal 
canals, commonly about 0.5 to 0.75 millimeter wide. 
Spicules (Pl. LXVI, fig. 62a, b, c, d, e).—Megascleres: (1) Style, smooth and slightly curved. 
Range of size, 160 to 180 w by 5 to 8 wu. (2) Tylote, smooth. Range of size, 160 to 190 w by 5h. 
Microscleres: (3) Isochelz arcuate 12 to 264 long. (4) Sigmata 18 to 36 u long. 
Skeletal framework (Pl. LXVI, figs. 27, 28).—Internal skeletal framework is a loose, irregular 
reticulum formed by styles, which may in places develop into spiculo-fibers. Meshes of reticulum are 
three to five sided; side of mesh about the length of a spicule, formed by one, two, or three spicules. 
Spongin present at the nodes (stained sections show it). In addition to the skeletal reticulum, the 
parenchyma contains some scattered tylotes. These may be grouped to form loose tracts. The tylotes 
are especially abundant in collenchymatous regions, and are more abundant in the ectosome than 
elsewhere. 
The megascleres of the dermal membrane are tylotes. In places they are scattered tangentially 
in the membrane, but very generally they project more or less radially, forming bunches or ridges. 
The wall of the papilla (Pl. LXI, fig. 26) is an extension of the dermal membrane, and the megascleres 
here, too, are tylotes, tangentially arranged and forming a reticulum, in the meshes of which are the 
pores. 
The whole parenchyma is loaded with sigmata; isochele abundant, but less abundant than the 
sigmata. Both sigmata and isochele are abundant in the general dermal membrane. ‘The wall of the 
papillz contains moderately abundant isochele and very few sigmata. 
Topsent established Lissodendoryx first as a subgenus of Dendoryx (1892) and later 
(1894a, p. 9) as a separate genus, for species which differ from Dendoryx (=Myxilla 
sens. str., Thiele, 1903; Lundbeck, 1905; Topsent, 1913) in having smooth styles as the 
skeletal megascleres. 
Dendy (1895, p. 29) would include the genus, and Dendoryx as well, under Myxilla, 
Schmidt. Topsent (1901), p. 19; 1904, p. 173) retains the genus as originally defined. 
Lundbeck (1905, p. 153) again brings up Dendy’s contention (1895) that the smooth- 
ness of the styles can not be used as a generic character, since species occur with styles 
that are intermediate between spined and smooth ones. From this point of view the 
genus should be merged in Dendoryx (= Myzxilla sens. stv.). But the Dendoryx species, 
Lundbeck maintains, are separable into two groups, in one of which the microscleres 
are ancore, in the other chelz arcuate. For the former Lundbeck reserves the name 
of Myxilla (sens. str., Topsent, 1913, p. 623), for the latter Lissodendoryx. 
