ART. 8 A NEW VARIETY OF SPOJfGE WILSON AND PENNEY 3 



8-10 mm. high and that the spicules composing it are to be classed as 

 ascending prostalia lateralia. 



There is no definite root tuft but there are some matted tangles 

 of long projecting spicules at the lower end of the body resembling 

 in appearance and composition those on the lateral surface. The 

 larger form of diact may reach in these basal tufts a length of 25 mm. 

 diameter at middle 100/x. These spicules commonly taper continu- 

 ously from the middle toward the ends, but in some spicules the 

 tapering ceases at a little distance from the extremity and the ends 

 are clavate. 



The parenchyma lia are diacts, stout and slender, strewn in all 

 directions through the parenchyma. There are many bundles of the 

 usual sort consisting of one stout diact (principal) accompanied by 

 slender ones (comitalia). The spicules are like those described above 

 as projecting from the lateral surface and basal end, except that the 

 class of stout oxydiacts includes relatively shorter and stouter spic- 

 ules grading down to 8-10 mm. by 40/x to 90/^, sometimes with smooth 

 ends. Just below the gastral surface and tangential to it still smaller 

 diacts of this class occur. They may be as small as 1 mm. by 28^ 

 near the middle; the actual middle as in the case of the larger spi- 

 cules may show bosses representing the vestigial rays; one end of 

 the spicule is occasionally rounded, the other end pointed. An 

 occasional stout hexact is found in the parenchyma ; these are prob- 

 ably autogastralia that have passed into the sponge wall during 

 maceration. Typically the parenchymalia in these sponges include 

 no hexacts. In the type Lambe finds the parenchymalia principalia 

 are stout smooth oxydiacts, 11.06 mm. by 100/*. Schulze notes the 

 occurrence of diacts, in general smooth but with roughened ends, 

 10 mm. long and over. Lambe finds the parenchymalia comitalia 

 are diacts up to 8.8 mm. by lOfi ; ends roughened, enlarged and blunt 

 pointed or rounded and club-shaped. The variety and the type 

 evidently agree well enough in these matters. Moreover the paren- 

 chymalia exhibit, in details, too much variation within the same 

 individual to afford good points for the distinguishing of species. 



The spicules regarded as of importance in the classification of these 

 sponges are the autodermalia, hypodermal pentacts, autogastralia 

 (there are no hypogastralia, paratangential bundles of parenchymal 

 diacts alone underlying the autogastralia, Ijima 1897, p. 47), oxyhex- 

 asters and discoctasters. 



Autodermalia. — As said, these have been lost over nearly the whole 

 surface. Fortunately they are still present in some small areas close 

 to the cloacal aperture. Both pentact and hexact forms occur. Four- 

 rayed forms (stauracts) were not observed but they may be normally 

 present. The rays are roughened (minutely spinose), blunt-pointed, 

 60/A to 70/t long. The spicules are similar to those recorded for the 



