SILICIOUS AND HORNY SPONGES WILSON. 375 



(d). Protriaenes and prodiaenes of the fringes and general sur- 

 face of the oscular areas, thickly crowded and like those guarding 

 the poriferous pits. 



3. Anatriaenes of radial bundles like those of type; some projecting 

 from general surface. Anatriaenes of under surface like those of 

 type. 



4. Sigmas of ectosome and interior show the same contrast in size 

 and shape as in the type. Those of the ectosome measure 20-32 [jl 

 in length, those of the interior 16-20 [>.. 



Holotype.— Cat. No. 21310, U.S.N.M. 



TETILLA (CINACHYRELLA) PATERIFERA, new species. 



Plate 39, figs. 6, 8 ; plate 48, fig. 4. 



Station D5169, three specimens. 



Sponge massive, somewhat elongated vertically, larger and round- 

 ed above, narrower below where the body is probably naturally 

 buried in the sand. The largest specimen is 95 mm. high with a 

 greatest diameter of 60 mm., the others not far from these dimen- 

 sions. A single osculum, terminal in two, lateral in one specimen, 

 leads from a cloaca. In one specimen the osculum is 4 mm. wide, 

 the cloaca 6 mm. deep, 5 mm. wide. In a second specimen the dimen- 

 sions are about the same. But in one specimen the osculum (terminal) 

 is 12 mm. wide, the cloaca 25 mm. deep, with a width of 12 mm. The 

 oscula are without fringes. The surface of the cloaca shows the 

 apertures of a few small efferent canals. 



The poriferous pits are very numerous, distributed over the whole 

 surface except the base, or only over the upper and lateral surfaces. 

 They are shallow, obviously sphinctrate, having a sharp margin 

 when they are contracted (pi. 39, fig. 6), a vague and rounded margin 

 when not contracted (pi. 39, fig. 8). The largest measures 8-10 mm. 

 in diameter, with a depth of 2-3 mm. They range down to small 

 ones about 1 mm. wide. In two of the specimens the pits do not 

 exceed 4-5 mm. in diameter. There is no fringe. The floor is smooth 

 and so perforated with pores as to be sieve-like. As bearing on the 

 ontogenetic and evolutionary origin of the pits, it is interesting to 

 note that over the lower lateral surface there are pits that are 

 scarcely depressed and other similar smooth pore areas that are not 

 depressed at all. Microscopic preparations show that between the 

 poriferous pits there are also some scattered pores. 



The surface in general between the poriferous pits is glabrous, 

 very feebly and minutely conulose. But over the lower lateral sur- 

 face are areas that are hirsute or produced into long downwardly 

 projecting slender root processes which include bundles of root 

 spicules. Such areas are more or less covered with shelly debris. 



