SrONGIIDA. 409 



4o. Reniera aquaeductus. 



Jleniera aquaeductus, Schmidt, Spong. Adr. Meer, p. ".'5, pi. vii. fig's, 

 ti, Cut, (')//. 



Two specimens, 65 and 70 millim. (2| and 2 J inches) long, 

 branched, forming very thick-walled tubes which open at the ex- 

 tremities of the branches, appear to represent this species. The 

 branches and stem are somewhat irregular in outline, and decidedly 

 compressed antero-postoriorly ; their surface is rendered uneven by 

 very low, almost obsolete ridges or eminences, though it is smooth 

 between these; maximum diameter of stem and branches 7 to 12 

 millim., that of lumen of tube 3 to 4 millim. Texture in spirit 

 firm, slightly compressible, moderately tough ; normal colour appa- 

 rently a pale brownish grey. Main skeleton — a rather irregular 

 network of primary and secondary spieulo-fibres, about 4 to 6 

 spicules broad, with much interstitial 1- or2-serial spicular network; 

 dermal skeleton composed of long compact spieulo-fibres, 6 to 12 

 spicules broad. Sarcode pale yellowish, slightly granular. Spi- 

 cules chiefly smooth acerate, curved, tapering gradually to sharp 

 points from about four diameters from ends, or subacuate, tapering 

 somewhat to the rounded end, or strictly acuate with well-rounded 

 head; size *17 to -19 by 'Oil millim. 



Hah. Port Darwin, between tide-marks. 



Distribution. Adriatic (Schmidt); Black Sea (Czerniavsl i/). 



The Adriatic form has a decided tough uniting material between 

 the ends of the spicules, and the tube is relatively wider in the speci- 

 men figured by Schmidt, otherwise the two forms appear to agree. 

 I find the spicules in a slide obtained from Prof. Schmidt to measure 

 •19 by -0095 millim. in average maximum dimensions ; he himself 

 gives (Atl. Geb. p. 40) •16S52 millim. for the length. 



"Reniera, yellow" of Carter (Ann. X. H. (5) vi. p. 48, pi. v. 

 fig. 17), from Ceylon, is probably not far from this species, but the 

 spicule appears to be about half as stout again as here. 



41. Reniera testudinaria. (Plate XXXIX. fig. D ; 

 Plate XLI. figs, u, a' .) 



Alcyonium testudinarium, Lamarck, Mem. Mus. Hist. Nat. i. p. 107. 



One of the present specimens originally formed part of a much 

 larger one, probably as much as 6 inches long by 6 broad by 2| 

 thick, covered with prominent jagged ridges ; the other is a fine 

 cup-shaped form, with wide mouth, thin edges, the ridges only ap- 

 pearing near the base. The skeleton-fibre is stout, strong, poly- 

 spicular, and of the Renierid type ; it is composed of stout, smooth, 

 cylindrical spicules, rounded at each end, sometimes tapering some- 

 what to the ends, and of a small number of smaller acerate forms, 

 tapering suddenly to their points ; average maximum size about - 32 

 by *016 millim. 



The species belongs to that group of Renierida^ which Mr. Carter, 

 in his "Notes Introductory to the Study and Classification of the 



