AET. 4 SPONGES OF CALIFORNIA de LAUBENFEL8 49 



tered out of the running sea water. These coatings were washed off 

 by a stronger current directed across them. The second day in the 

 aquarium, areas adjacent to the cuts made in detaching the specimen 

 turned dull brown, as did bits plunged in formalin. On this day the 

 areas formerly lavender were clear blue. On the third day in the 

 aquarium the yellow areas were more ochraceous than before. The 

 oscules still opened and closed vigorously. On the sixth day the latter 

 evidence of vitality was still in evidence, but on the seventh the 

 oscules were closed and remained closed. On the twelfth day there 

 was still no odor of putrefaction, but a funguslike growth, or fila- 

 mentous bacteria, attacked the cut areas. On the thirteenth day the 

 entire specimen was a dull drab and was dead or nearly so. The 

 dried specimen became dull yellow, the alcohol specimen, dull brown. 

 Oscules, largely grouped on the summit, and when fully open nearly 

 10 mm in diameter. They are very readily closed by sphinctrate 

 tissue about them. Into many of them hung fleshy, membranous 

 sleeves, of very perplexing function. Why they did not act as valves 

 and close the oscule is a mystery. Perhaps in life, with a strong 

 current, they project as oscular chimneys; if so, they would protrude 

 2 or 3 cm. The aquarium specimen showed no strong oscular current, 

 but much evidence of strong inhalent current. This is probably be- 

 cause the exhalent current had much larger exit at the cut surface 

 than at the oscules. There were amoeboid cells and a few spicules 

 scattered in the otherwise homogeneous structure of these mem- 

 branous sleeves. Pores, in pore areas several centimeters square. 

 The pore canal is typically 1.5 to 3 mm. in diameter. It is closed 

 on the surface by a sieve with 3 to 6 round openings about 300/1, in 

 diameter. In the area between the pores and the oscules were a few 

 scattered round oi^enings about 1 mm in diameter. I could not de- 

 termine whether they were inhalent or exhalent. Surface, super- 

 ficially smooth. 



Ectosomal specialization, the surface for a depth of about 2 mm is 

 densely packed with spicules, the outer ones arranged points out- 

 ward as in Suherites^ but they are not smaller than the endosomal 

 spicules. Endosomal structure, resembling nonboring examples of 

 Cliona^ with some very large cloacal canals nearly 1 cm in diameter, 

 and with woody tracts of spicules about 2 mm in diameter making a 

 vague reticulation. 



Spicules, tylostyles (fig. 23) ; size, 14/a by 300/x to V6p. by 310;u. A 

 very few are much thinner and somewhat shorter, these are evidently 

 developmental stages. The uniformity in size of the spicules in 

 general is very remarkable. 

 107704—32 i 



