REPORT ON THE HEXACTINELLIDA. 287 



spicules differ essentially from those of the corresponding portions in Farrea occa. The 

 anchor-hooks in many of the gastral clavulse seem to be especially long (PI. LXXIV. 

 fig. 12), and the hexasters are in part very divergent. Though most of the latter have 

 a general resemblance to the oxyhexasters of Farrea occa, they differ' from the latter in 

 the greater thickness of their principal rays (PI. LXXIV. fig. 8). Besides these, some- 

 what larger hexasters occur with weakly developed principal rays, which divide into four 

 short S-shaped terminals, disposed in a perianth-like whorl and tipped with a small knob. 

 (PI. LXXIV. fig. 9). 



4. Farrea clavigera, n. sp. (PI. LXXV.). 



Near the Banda Islands (Station 194, lat. 4° 34' S., long. 129° 57' 30" E.), from a 

 depth of 200 to 360 fathoms and volcanic mud ground, a Farrea was captured which in 

 external appearance differed essentially from all hitherto described forms. This sponge 

 forms a straiglit tubular stem about as broad and as long as a finger, with walls 1*5 to 

 2 mm. in thickness. It becomes gradually wider towards the upper end, attaining 

 a diameter of 20 mm., and rising at right angles to a compact smooth basal expansion, 

 which is directly attached to the solid substratum. Just above the solid base the internal 

 lumen has a width of 3 mm., and is continued obliquely downwards into an external 

 groove-like keel. At a height of 12 mm. the first lateral branch is given off, with a 

 diameter of 8 mm., while further up several branches fork off in irregular distribution, in 

 a somewhat transverse direction to the main stem. The latter seems to divide superiorly 

 into two large branches which are unfortunately broken ofi". While some of the transverse 

 tubes are broken ofi" quite close to the main stem, others exhibit dichotomy into two very 

 divergent branches. It is interesting that a very similar form has been described by 

 Oscar Schmidt under the title Farrea facunda from among the Hexactinellids of the 

 Bay of Mexico. It is figured in the work already referred to, pi. vii. fig. 1a. 



The dictyonal framework does not vary essentially from that described in Farrea occa. 

 Inferiorly it increases, on the one hand, in thickness, and on the other very markedly in 

 the fineness of its meshes. The basal portion becomes a thick, stone-hard, very finely 

 porous mass, in the meshes of which countless small hexacts occur, in part free, and in 

 part fused to the adjacent framework. Isolated parenehymalia are further represented by 

 uncinates and hexasters. The former seem to be comparatively long and narrow. Among 

 the latter I have observed the form which occurs so abundantly in Farrea occa, but in 

 much more sparse distribution. Whether a second form of hexaster, characterised by 

 short principals and very long terminals, and occurring abundantly in some regions (PI. 

 LXXV. fig. 6), really belongs to this Farrea, or has been intruded from some other 

 Hexactinellid, I cannot unfortunately determine with certainty. 



The dermal pentacts resemble in general the corresponding dermalia of Farrea occa. 



