SPONOIIDA. 407 



name, for want of characters by which to identify species with 

 others which I know merely by descriptions ; I have, however, given 

 descriptions in these cases, in order that the species may be identified 

 (if possible) by future comparisons with specimens of species to 

 which I have not access at present. 



EENIERA, Nardo. 



This genus is distinguished by the regularity of its main skeleton, 

 the small size of its spicules, and the want of an evident distinct 

 dermal skeleton. The latter point, however, is not very satisfactorily 

 indicated in all the species which seem otherwise referable to the 

 genus. 



37. Reniera indistincta, var. 



Isodictya indistincta, Bowerhank, Man. Brit. Spong. ii. p. 290, iii. 

 pi. li. figs. 1-4, iv. p. 119. 



A small specimen in spirit, incrusting stones. The surface 

 is smooth, formed of a thin but strong membrane,i of grey colour 

 (in spirit), penetrated by moderately numerous round perforations, 

 ■5 millim. across. Vents few, occasionally slightly elevated, 2 to 3 

 mUlim. in diameter. Main skeleton agreeing fairly with the typical 

 specimen of the species ; a dermal network, uni- to bispioular (in 

 the type specimen it appears to exist, although Bowerbank denies 

 it, but it is somewhat irregular there). Barcode yellowish brown,' 

 slightly granular (it is more yellow in the type). Spicules ; shape 

 as in type ; size -16 by •0063 millim., the same as in the type. The 

 vents are rather smaller in the type, and the colour in the dry state 

 is reddish brown ; but the agreement in the characters on the whole 

 is so close that I have little hesitation in making this identifi- 

 cation. 



Hob. Prince of Wales Channel, Torres Straits, 7-9 fms. 



Distribution. British Islands and Guernsey (Bowerbank). 



A specimen without distinct vents, but with a curious system of 

 branching grooves on the surface, and of a dark greenish colour, 

 appears to be also referable to this form. 



Mab. Alert Island, Torres Straits, 7 fms. 



38. Eeniera scyphonoides. 



Spongia scyphonoides, Laniarck, Ann. Mtis. Hist. Nat. xx. p. 437. 



An elegant, slightly tortuous, tubular Beniera, 45 millim. high, 

 tapering from its subcylindrical basal portion, which is 3-4 nullim. 

 thick, to an elliptical, slightly bullate summit, preceded immediately 

 by a more decidedly flattened portion, the two diameters of which 

 are respectively 4 and 8 millim. Long and short diameters of mouth 

 of tube 2| and 4 millim. respectively. Two small vents, 1 millim. in 

 diameter, open on one margin of the compressed part of the sponge, 

 and one of about -4 millim. diameter on the opposite margin. 



