PORIFERA. II. 



I 4 I 



Locality: The Faroe Islands, 6 miles north to west of Kalso, depth 60 fathoms, 2 miles off 

 Borovig, depth 20—30 fathoms, at the north end of Nolso, depth ca. 100 fathoms (Th. Mortensen); 

 northwest of Stromo, depth 60 fathoms (Ad. Jensen, the cruise of the Michael Sars 1902). 



Geogr. disfr. This species, which was originally only known from the Mediterranean, seems to 

 be rather widely spread. Triest (Lieberkuhn); the canals of Venice (Schmidt); Algeria (Schmidt); at 

 the Azores, depth 69 fathoms, off the northern coast of Spain, depth 72 fathoms, 45 48' Lat. N., 5 58' 

 Long. W., depth 85 fathoms («l'Hirondelle», Topsent); at the French coast in the Channel at Luc and 

 Roscoff (Topsent). The species is thus at present known from the Azores to the Faroe Islands. Its 

 bathymetrical range is from ca. 5 fathoms (in the Channel) to ca. 100 fathoms (at the Faroe Islands). 



3. M. fimbriata Bow. 

 PL IV, Figs. 9—10. PI. XIV, Fig. 5 a— i. 



1S64. Isodictya fimbriata Bowerbank, Mon. of Brit. Spong. II, 337, 43. 



1874. Bowerbank, ibid. Ill, 147, PI. LVIII, figs. 7—14. 



1880. Amphilecfus fimbriatus Vosmaer, Notes from the Leyden Mus. II, 116, 20. 



Cushion-shaped or formed as a round lump, sometimes slightly lobed. The surface even, very 

 slightly shaggy. The dermal membrane solid, supported by penicillate bundles oj dermal spicules. Oscula 

 scattered on the surface. The skeleton a polyspicular, most frequently irregular network of triangular or 

 quadrangular meshes. Spicnla : Megasclera: the skeletal spicules acanthostyli , rather densely spined, 

 0-26 — 0-4 j""", the dermal spicules toruo/a 0-2 j — o-j2""" ; inicrosclcra two forms of ancora spatulifera, 

 large ones 0-064 — o-oq""", small ones 0-022 — o-ojj""". 



This species has a more or less lumpy, sometimes somewhat lobed form. It may be attached 

 to different things; when growing on a rather extended substratum, as shells, it has often a flat, 

 cushion-like form, but when it grows 011 worm-tubes, Hydroids, Bryozoa or the like, it becomes more 

 roundish and lumpy. The smaller specimens seem to be the more regular ones, while the larger ones 

 most frequently show the lobed or more irregular form. The specimens figured by Bowerbank 1. c, 

 which are all small, are thus rather regularly roundish, and he describes also the form as snearly 

 globular, or more or less roundish-. The largest specimens mentioned by Bowerbank were of the 

 size of a walnut, whereas I have before me considerably larger specimens; the largest one, which is 

 of an irregular, longish form, has a greatest extent of about 8o mm , and then we have a series of speci- 

 mens in evenly decreasing sizes, the smallest one has a greatest extent of i2 mm . The colour (in spirit) 

 is most frequently more or less dark-brown, to almost black, a few specimens are of a lighter tawny 

 colour. I suppose that the fresh sponge after its death becomes dark by the influence of the light or 

 in spirit, as the dark specimens, when cut through, are seen to be lighter inside, and the light colour 

 begins just under the surface. As stated by Bowerbank, the sponge also becomes dark when dried. 

 The consistency is somewhat elastic, and the sponge may be rather hard and firm, or softer and looser. 

 The surface is even and apparently smooth, but under the magnifying glass it is seen to be slightly 

 shaggy from projecting spicules. The dermal membrane is a rather solid and not especially thin film, 

 which may very easily be isolated; it is supported by projecting bundles of dermal spicules spread in a 

 penicillate way. These bundles are most frequently very close-set; they may be erect or more or less 



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