68 



with the greatest difficulty, while at the other end they are very large and crooked inwards. 

 Usually only 3 such teeth appear; but in some (fig. 32 b) it was evident that behind these 

 there were still a couple of teeth; so that the teeth were on the whole 5 in uuniber. Whether 

 this applies to all or only to some, the position of which happened to be more favorable, I 

 am not able with certainty to decide. By means of these innumerable microscopic „claws" 

 which project everywhere from the surface of the sponge, all the more minute animals and 

 the light floating particles which come into immediate contact with the sponge, become atta- 

 ched to it, and thus probably fulfil an essential condition for its nourishment. The specimens 

 which I got up in the dredge shewed also a very peculiar appearance; an infinity of small 

 creatures adhering to it, especially various sorts of Calanus, small Amphipodes, and young 

 Annelides, which adhered so closely that I had the greatest difficulty in cleansing the sponge 

 from all these extraneous bodies. These small animals came probably for the most part in 

 contact with the sponge, by being taken up in the dredge together with it; but that a similar 

 occurrence, even if on a smaller scale, would take place normally in the deep, I consider very 

 probable. As there appears here no trace of any pores interior cavity or oscula, the ali- 

 mentation must be supposed to be eft'ected by a process dift'erent from that which takes 

 place where these apparatus exist. 



If a small piece from the end of a branch is taken and treated with a weak solution 

 of caustic potass to make it transparent, there will appear in it under the microscope (fig. 

 22) a peculiar structure of the parenchym, which is not found elsewhere. It will be observed 

 that there are imbedded in this part numerous small globular bodies, with finely granular 

 contents, occurring in greatest numbers near the surface, but which seem also to be found 

 in the central part. It seems indubitable that we have here the place from which the repro- 

 duction of the sponge proceeds. In one of the specimens obtained (fig. 16) there were ob- 

 served in the branches themselves, and partly also in the main stem, imbedded here and there 

 in the parenchym, between the interior spicular axis and the e.xterior skin, several globular 

 bodies many times larger, easily discernible by the naked eye from their darker yellowish red 

 color and greater opacity. These bodies, which under the microscope exlaibited a cellular 

 consistency (see fig. 34) are undoubtedly the fully developed eggs or gemmules. These had 

 certainly not developed themselves in the place where they lay imbedded, but had in all pro- 

 bability been generated at the extremities of the branches, and in the process of development 

 at last become free or released from the cellular tissue wherein they had originated, and 

 thence distributed themselves around in the soft parenchym of the sponge. 



I have only found this remarkable sponge in one single locality, namely at the fishing 

 station Skraaven in Lofoten at the great depth of 300 fathoms on soft clay bottom. The 

 specimens obtained are of very unequal size, but exhibit all the same characteristic shrub- 

 like form. The largest and most perfect specimen, which is delineated fig. 17, had 14 bran- 

 ches springing 'Out from the stem at dift'erent heights ; the lowest about half the length of 

 the main stem, not reckoning the root; the others successively shorter. Close under the 



