206 THE VOYAGE OF H.M.S. CHALLENGER. 



project freely, and, together with a dense dermal crust of small, projecting, tylostylote 

 spicules, give rise to the hispid character of the head. The interspaces between the 

 radiating bands of spiculo-fibre are occupied by loosely and irregularly scattered tylo- 

 stylote spicules. 



Spicules. — Megasclera ; (1) very long, straight, slender, smooth styli or subtylostyli, 

 very finely and gradually pointed at the apex ; size about 1'8 by 0'016 mm. (2) Much 

 smaller, straight, slender tylostyli with well-developed, subglobular heads, and very sharply 

 and gradually pointed at the apex ; size rather variable, about 0-35 by 0-0063 mm. 



As regards spiculation there is but little characteristic about this species ; the great 

 slenderness of the long stylote spicules, and the presence of a fairly well defined dermal 

 crust of smaller tylostyli may be noted. The external form, though variable, is very 

 characteristic ; the elongated oval shape of the head and the relative shortness of the 

 stalk being its prominent features. 



Zoca/%.— Station 75, July 2, 1873 ; lat. 38° 38' 0" N., long. 28° 28' 30" W.; off the 

 Azores ; depth, 450 fathoms ; bottom, volcanic mud. Eiglit specimens. 



Suberites sjni'alis, Ridley and Dendy (PI. XXV. fig. 1). 



1886. Suherltes spiralis, Ridley and Dendy, Ann. and Mag. Nat. Hist., ser. 5, vol. xviii. p. 486.' 



Sponge (PI. XXV. fig. 1) erect, stipitate ; cylindrical, with the stalk produced 

 upwards, as an axis, right through the body of the sponge. Height 88 mm.; length 

 of stalk 31 mm.; diameter of stalk 2 mm.; of body 6 mm. Colour in spirit pale 

 yellow. Texture of stalk and axis very dense and firm ; of body fairly firm, but rather 

 open and compressible. Surface very minutely hispid. Oscula scattered over the 

 body of the sponge. 



Skeleton. — Consisting of a dense, stout, central axis of longitudinally placed spicules, 

 from which, in the bod)^ of the sponge, radiate loose fibres to the surface, arranged in 

 a somewhat spiral manner and terminating in loose, radiating brushes of smaller spicules 

 with outwardly directed apices. 



Spicules. — Megasclera; (1) long, slender, straight, or nearly straight, sharp-pointed 

 tylostyli ; with well-marked, but not very large, subglobular heads ; size about 1 -0 ):)y 

 0'013 nmi. ; these constitute the skeleton fibres. (2) Similar, but much smaller spicules, 

 occurring in the surface brushes, length about 0'4 mm,, but not very constant. 



In the presence of a distinct axis with radiating fibres this sponge resembles the 

 Axiuellidaj. The habit is decidedly that of an Axinellid, and it seems to strengthen the 

 possibility of a close relationship between the Axinellidje and Suberitidae. The peculiar 

 spiral arangement of the skeleton fibres in the body of the sponge is to be found still 

 more distinctly shown in Stylocordyla stijyitata, var. glohosa {vide woodcut, Fig. 9). 



Locality. — Off the south-west coast of Patagonia. One specimen. 



