THE ANNALS ^ 



AND 



MAGAZINE OF NATURAL HISTORY. 



[FOURTH SERIES.] 

 No. 8. AUGUST 1868. 



VIII. — On a remarkable Sponge from the North Sea. 

 By S. LovEN*. 



[Plate VI.] 



The Swedish Museum of Natural History at Stockholm pos- 

 sesses two specimens of a siliceous sponge which seem to well de- 

 serve a careful examination. One of them belongs to collections 

 made by myself long ago on the coasts of Finmark, while the 

 other was obtained last year by M. Gr. von Yhlen in the North 

 Sea, on the Storeggen, at the depth of about two hundred 

 fathoms, and presented by him to the Museum. Both are 

 preserved in spirits. 



The external form of this sponge is peculiar — a clavate 

 body, which may be called the head, supported by a slender 

 stem thrice as long, round, and somewhat curved, the inferior 

 end of which has been attached to the bottom of the sea by 

 numerous roots (PL VI. fig. 1). The whole sponge without 

 the roots is 52 millimetres high, the length of the head 13 mil- 

 lims., that of the stem 39 millims. The colour is pale yel- 

 lowish grey. The transverse section of the head is oval ; its 

 upper surface is flattened, and in one specimen quite plain ; 

 in the other (fig. 2) it has a large, oblong, well-defined aper- 

 ture, from which canals, separated by irregular partitions, are 

 seen to penetrate into the interior. This is the well-known 

 osculum (Bowerbank), which the living Sponge is capable of 

 opening and closing at will, and its interior canal-system. 

 The surface of the head (fig. 3) is smooth, finely and irregu- 

 larly reticulated, with scattered and somewhat larger lacunae, 

 and, when seen under the microscope, seems as if covered 

 with very fine hairs from projecting spicules. The stem, 

 which is hard, firm, and elastic, has a distinct, finely hairy 



* Translated from the ' Ofversigt af K. Vetenskaps Akademiens For- 

 handlingar/ Stockholm, 1868, p. lOo. 



Ann, & Mag. N. Hist. Ser. 4. Vol. i\, 6 



