THE MOUNT DESERT REGION 105 



This species was found only once in this region, at Station 

 97, in 72 feet of water, and it was encrusting an old barnacle 

 shell. In the living condition it is bright red. At Woods 

 Hole, and Beaufort, North Carolina, it is an erect, intricately 

 branched sponge. 



Skeleton. This consists of vertical columns or fibers, 2 or 4 

 spicules in thickness. Echinating spicules are arranged in 

 unilateral tufts. 



Spicules. Megascleres. 1) Styli are smooth, slender, 

 slightly fusiform, often rather bluntly pointed and are the 

 chief skeletal element. In some cases the head end is slightly 

 inflated with an indistinct neck between the fusiform shaft 

 and head of the spicules. No spines could be detected, 

 although they were sought for. These spicules vary from 

 .243 mm. to .324 mm. in length, with a mode at ,284 mm. 

 2) Small spinose styli, which frequently have slightly enlarged 

 heads, are present but are not so abundant as the larger 

 smooth styli. They taper gradually from the head to a sharp 

 point and vary in length from .105 mm. to .203 mm., with 

 the mode at .145 mm. 3) Large spinose styli, with slightly 

 enlarged and heavily spined heads, are about as abundant as 

 the small spinose styli. These spicules taper gradually from 

 the head to a sharp point. The spination becomes progres- 

 sively less heavy from the head to the tip. They vary in 

 length from .284 mm. to .405 mm. This class of spicules is 

 absent in specimens from Woods Hole, and the measurements 

 given by George and Wilson for the spinose styli from ma- 

 terial taken at Beaufort would not include them. 



Microscleres. These are stout isochelae, with no variation 

 in size, and measure .121 mm. in length. These isochelae have 

 usually 2 teeth, although a few with 3 or 4 teeth are found. 



Remarks. George and Wilson record the presence of toxa 

 in ^considerable abundance' in the Beaufort specimens, and 

 in an examination of material from Woods Hole these spicules 

 were found to be excessively rare. No toxa were found after 

 a careful search in the specimens from this region. Thus, 

 this specimen differs mainly in the presence of large spinose 



