424 REVISION of THE MONAXoKID SPONGES, ili., 



AxiNELLA AURANTiACA. (PI. xxii., fig.l; and text-fig.l9). 



Introductory. — Fortunately Lendenfeld has furnished us with a 

 figure of this species, and the actual specimen from which the 

 figure Avas taken is extant. Otherwise, owing to a mistake in the 

 original description, — wherein the spicules are stated to be styli, 

 instead of oxea (with only occasional styli) and flexuous strongyla 

 — the species in all probability could never have been identified. 

 But, with this exception, the description is fairly appropriate; 

 and the omission from it of any mention of strongyla is attribut- 

 able to the fact that these spicules are sometimes sufficiently scarce 

 to be easily overlooked. The inaccuracies in this case, therefore, 

 are to be explained as due to careless observation, and not to the 

 commingling of the descriptions of two different species. 



Description. — Sponge arborescent, erect, stipitate; with cylin- 

 drical pointed branches, which multiply by frequent dichotomy and 

 occasionally anastomose at points of contact. The branches in- 

 crease in stoutness towards the base, and may there attain a dia- 

 meter of 12 nun. The surface is minutely granular, owing to the 

 impingement upon it at very close intervals of outwardly running 

 skeletal fibres. There is present a very thin, but well-defined der- 

 mal membrane, which remains intact when the sponge is carefully 

 macerated with caustic potash solution. Small oscula, about 1 

 mm. in diameter, occur scattered at rather distant intervals. The 

 canals leading into the oscula, — not only the main canals which 

 open into the oscula, but also their chief tributaries — run for some 

 distance immediately beneath the dermal membrane, and are faintly 

 discernible through it. The specimen of Lendenfeld's figure 

 measures 120 mm. in height, and is in an unusual degree profusely 

 branched; large specimens may attain a height of 200 mm. The 

 colour in life, according to the original description, is bright 

 orange; spirit specimens are yellowish-gxey, and those preserved 

 in the dry state whitish. Except for a soft superficial layer about 

 1-5 mm. in thickness, the consistency is in alcohol very firm and 

 tough, particularly in the older portions of the sponge. Dry speci- 

 mens vary in consistency and texture, and present a very different 



