REPORT ON THE HEXACTINELLIDA. 295 



at the bfise, but gradually decrease in diameter towards the pointed extremity, and are 

 laterally compressed like the blade of a knife, with the edge turned inwards and the 

 back towards the exterior (PI. LXXVIII. figs. 3, 5). 



The pentacts of the gastral skeleton generally resemble those of the dermal skeleton, 

 but more frequently exhibit a gently arched or even markedly protruding knob-like 

 elevation in place of the undeveloped sixth ray. The scopulse are tolerably abundant ; 

 and resemble the dermal forms of the first type. The expanded end of the posteriorly 

 pointed stalk bears a knot-like swelling with four to five slightly diverging prongs. The 

 slender stalk of the prongs exhiljits a club-shaped extremity beset with small barbs (PI. 

 LXXVIII. fig. 4). 



The structure of the soft parts does not differ in any essential feature from that 

 described in Eurete semperi. 



3. Eurete farreopsis, Carter (PL LXXIX. figs. 5-8). 



The species of Eurete figured in PI. LXXIX. fig. 5 is a tubular feltwork, which in 

 several places is firmly attached to the solid substratum. The tubes have a comparatively 

 small diameter (of 5 to 8 mm.) and only a moderate peripheral thickness. The form was 

 obtained near the Little Ki Island (Station 192, lat. 5° 49' 15" S., long. 132° 14' 15" E.) 

 from a depth of 129 fathoms and a blue mud ground. It was thus found in the same 

 locality as Eurete seynperi. In the structure of its skeletal elements it resembles very 

 closely the Eurete farreopsis described by Carter in 1877,^ and represented in a very 

 efi'ective figure (pi. ix. figs. 1-7). The identity of the two forms is unquestionable. 

 The dictyonal framework, in which the square form of meshes predominates, consists of 

 smooth or only slightly tubercled beams, and of more or less markedly thickened and 

 roughened nodes of intersection. Simple, rough, minute oxyhexacts occur in the 

 parenchyma, especially in the older and lower portions, and are in part fused by one ray 

 to the general framework. Besides these, the parenchyma includes small discohexasters 

 with terminal knobs on the four divergent, moderately long, often perianth-like, curved 

 terminal rays, and in sparse occurrence the familiar uncinates beset round about with 

 appressed barbs. 



The dermal skeleton agrees perfectly with the gastral. The pentacts are provided on 

 both sides with slightly curved tangential rays, somewhat rough at the rounded off" 

 extremities, and a somewhat longer straight radial, in which the narrowed, roughened, 

 terminal portion is moderately pointed or rounded ofi". 



Just as the dermal and gastral pentacts resemble one another, so do the peculiarly 

 shaped scopulse which occur beside them ; but the latter are characterised by the sharp 

 break-like bend of the terminal rays. Each of these thin bent stalks, w^hich diverge 



1 Ann. and Mag. Nat. Hist, ser. 4, vol. xix. i^. 122. 



