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cular pattern , distinctly visible on the dermal surface, is concealed to 

 a great extent on the gastral, owing to the greater abundance of pinu - 

 les on this side. The root- tuft is free oi Palythoa, is laterally com- 

 pressed and of silky appearance , without the twisting of fibres but 

 showing a simple curvature in a plane perpendicular to the general 

 gastral surface. No marginal cuff is present. — A full-grown speci- 

 men measures: body 120 mm long, 66 mm broad and 46 mm thick 

 (at the thickest portion) ; the reflected portion of the gastral surface 

 33 mm broad on the lateral side; root-tuft 130 mm long and 6 mm by 

 10 mm thick. 



Within the body, the root- tuft breaks up into a number of slightly 

 diverging strands, without forming a solid columella. The root-fibres 

 are of three kinds: 1) thick smooth fibres, the lower ends of which 

 were always found broken off; 2) thinner pronged fibres with a two- 

 teethed anchor at the lower end; and 3) very thin wavy fibres, with 

 at least one end crooked in more than a semicircle. The last kind of 

 spicules is also abundant at the basal pad , where it seems to replace 

 the acanthophores of other Hyalonema species. — The pinuli are 

 0,2 mm high, with the arm of the basal cross 0, 1 mm long. Their free 

 ray, thickly beset with spines, presents a bushy cypress-like shape 

 0,04 — 0,05 mm broad at the middle. The dermal and the gastral pi- 

 nuli differ in so far that the spines of the latter are more strongly 

 developed and those more inferiorly situated start from the stem al- 

 most at right angles and then bend upwards, instead of being obliquely 

 directed from the point of origin. — Macramphidiscs sparsely present, 

 0,117 mm long, 0,06 mm broad; umbel bell-shaped, 17-rayed, about 

 as long as V4 of the entire spicule. — Mesamphidiscs 0,08 mm long, 

 0,025 mm broad; umbel 7 or 8 rayed, somewhat longer than '/s the 

 entire length. — Micramphidiscs of various sizes, down to those 

 0,025 mm long, are very abundant. — The micro-oxyhexacts of the 

 parenchyma are represented by numerous prickled oxyhexacts with 

 straight arms 0,08 — 0, 14 mm long. Together with these, there is also 

 found an abundance of thin, smoth, spindle-like needles 0,09 — 0,14 mm 

 long. — Parenchymal macrosclerae seem to offer but little characte- 

 ristic points. 



H. reflexum was obtained in several examples from depth of over 

 200 fathoms. Perhaps this species deserves to be erected into a se- 

 parate new genus. 



Hyalonema Oivstoni sp. nov. 

 In form this species somewhat resembles H. Thomsoni. The oscu- 

 lar area projects in a central-cone, 13 — 23 mm above the margin, at 



23* 



