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Guldbrandsoerne) in a depth of 120300 fathoms on soft clay bottom. I have not yet found 

 it in any other place ; but it is probable that when the great depths off our coast shall have 

 been more closely examined, this sponge will also be found in many other places. 



As regards the systematic place of this sponge, it is according to the nature of the 

 spicula easy to see that it is a siliceous sponge ; likewise the arrangement of the spicula 

 shews that it belongs to the 1 s .' group or sub-order established by Bowerbank characterised 

 by ,,spiculo-radiate skeletons" ; it is further easy to see that it belongs to the group named 

 by Oscar Smith Corticata and for which the well known genus Tethea is the type. But on 

 the other hand it will not agree with any of the formerly established genera, from which it 

 differs as well by its characteristic form, as by its peculiar attachment and fistular oscula. 



The genus may be characterised in the following manner. 



Gen. Trichostemma. M. Sars. 



Spongia silicea, simplex, libera, in limo demersa et hie fimbria spiculorum setifor- 

 mium, flexibilium, radiantium sustentata, cortice crasso compacto circumdata, interiore multo 

 minus compacto, parenchymatoso, lacunis numerosis irregularibus trajecto. Oscula numerosa 

 tubifprmia in facie superiore libere prominentia. Sceletum ex spiculis acuformibus fasciculato- 

 racliantibus compositum, aliis brevissimis capite globoso in cortice densissime accumulatis, 

 aliis multo longioribus, fasciculos tenues parenchyma et corticem trajicientes formantibus. 



Spec. Trichostemma hemisphaericiim. M. Sars. 



Forma regulariter hemisplio?rica, facie inferiore plana vel paulo c-oncava, superiore 

 sequaliter convexa, limbo distincto circular! spiculis setiformibus tenuissimis et longissimis 

 ubique radiantibus fimbriam latam et elegantissimam formantibus ornato. Color albido-cinereus. 

 Diametros speciminum majorum fimbria exclusa 43 Mm. altitudo 20 Mm. 



Habitat non infrequens ad insulas "Lofotenses in profunditate 120300 orgyarum, 

 fundo argillaceo. 



13, Cladorhiza abyssicola, M, Sars, 



nov. o-pn. ct spec. 

 (PI. VI. fig. 16-34). 



This remarkable sponge living in the great depths at Lofoten, has also such a peculiar 

 and characteristic exterior, that it is immediately known from all other sponges; and indeed 

 one might, at a cursory glance, be tempted not to consider it to be a sponge at all, but rather 



some animal of the polyp kind, for instance a Sertularide. or a Polyzoon. 



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