SPONGES COLLECTED IN PORTO RICO. 
387 
spicules vary hut little. Total diameter from ray apex to ray apex is 28 jn or close to it, with a ray 
length of 6 fi. The spicule resembles that figured by Schmidt, rather than the other extreme present 
in Schulze’s specimens; differing from the latter in having a longer, sharper ray, outline of which is 
not convex, but is either straight or slightly concave. About nine rays are seen round the edge when 
the equator of the spicule is brought into focus. 
In the interior of the sponge the spicules vary more. Spherasters similar to those of the cortex 
are abundant, with a ray length 6 to 8 ju. Smaller sizes of same spicule, down to 10 ju diameter, are 
present. Forms with relatively larger body and shorter rays are also fairly common. In these, total 
diameter of which is 12 to 20 //, the rays are mere projections, 2 ju and less in length, on the surface; 
outline of ray straight or frequently convex. Such spicules resemble those described by Schulze. 
Intermediate forms between the two extremes are fairly common; total diameter, 28 to 32 ju; ray 
length, 3 to 4 ju; rays with straight or slightly concave outline. 
Order 3. M0NAX0NIDA Ridley & Dendy. 
Silicious sponges in which the megascleres are uniaxial. 
Suborder I. HADROMERINA Topsent. 
Compact sponges, with skeleton radiately arranged, or without order, rarely forming spiculo- 
fibers, not reticulated, and usually without spongin. Megascleres, monactinal or diactinal, as a rule of 
a single kind. Microscleres, when present, some form of aster or mieroxea, never chela; or sigmata. 
Family COPPATIIPTf Topsent. 
Megascleres diactinal. Body massive, rarely cyatliiform. Microscleres absent, or when present 
euasters with which streptasters may be associated. 
Genus COPPATIAS Sollas (1888). 
Megascleres arranged partly in radiating fibers, partly scattered loosely in the choanosome; in the 
ectosome they lie tangentially. Microscleres are euasters. 
Coppatias solidissima, n. sp. 
Station 6079, two specimens, both fragments. 
Both fragments elongated, flattened lobes, about 20 mm. thick and twice as wide, each prolonged 
above into a slender digitate solid process, rounded at the end. Total length of longest fragment 120 
mm. Oscula, few in number, about 3 mm. diameter, all on one side. Consistency firm and hard; 
surface nearly covered with incrustations. Color: Exterior, dark slate-brown, with tinge of purple; 
colorless within. 
Subdermal cavities fairly well developed. Granular pigment cells (brown), 16 to 20 // diameter, 
are scattered through whole body, but are densely crowded in dermal membrane, and internal to it 
for a varying distance, in places throughout the thickness occupied by the cortical brushes of spicules. 
Pores, about 40 // diameter, are grouped, four or live together, in small transparent pore areas, separated 
by heavily pigmented tissue. The arrangement is such that the pigmented tissue forms a network of 
trabeculae. (In this species, as elsewhere, the appearance of the dermal membrane must varv from 
time to time. ) 
Skeleton. — -Megascleres : (1) Oxea, smooth, somewhat curved, 1 mm. by 28 //. Smaller sizes, 
doubtless younger stages of this, the chief, spicule, are common. These large oxeas are arranged: a, in 
radial cortical brushes; b, from some of the latter, bundles are prolonged into the interior; c, in 
numerous longitudinal main bundles, which are not very distinctly marked off from one another, the 
bundle arrangement most distinct in transverse section; < /, scattered irregularly through the sponge 
body. The oxea is occasionally found with one rounded end (strongyloxea). It is noteworthy 
that occasionally a truene spicule is found properly placed among the cortical oxeas. In looking 
