Samtlige Svampe vare opbevarede paa Alkohol; aogle faa 

 vare indtørrede pan Grand af Karrenes mindre fuld- 

 stændige Lukning og Alkoholens deraf følgende Fordamp- 

 ning. Paa en hel Del Etiketter er Paaskriften skeet med 

 Anilin-Blæk, saa den for Tiden er ulæselig, og det er for- 

 gjæves forsøgt at fremkalde denne igjen ved forskjellige 

 Midler. Følgen heraf er. at Findestedet ikke kan angives 

 for en hel Del af de beskrevne Svampe. 



Hvorvel Svampene i det Hele er vel konserverede, har 

 det dog ikke været mig muligt af en eneste at faa Prepa- 

 rater, paa hvilke jeg kunde faa Rede paa Kanalsystem, 

 eller overhovedet paa Bløddelenes Struktur. Det eneste 

 Holdepunkt for Svampenes Bestemmelse har derfor været 

 Kiselnaalenes Form og Anordning. Den ydre Formgiver, 

 som bekjendt hos disse Dyr. kun i ganske faa Tilfælde 

 mere eller mindre paalidelige Holdepunkter. Kiselnaalenes 

 Form og Anordning synes derimod at maatte kunne bruges 

 som GJTundlag for en systematisk Inddeling. Det her be- 

 handlede Antal Svampe er imidlertid for lidet til at grund- 

 lægge et System paa. og jeg indskrænker mig derfor til at 

 oidne Materialet efter Kiselnaalenes Form. og vil jeg, hvor 

 det har lykkets mig at identificere en Form med en allerede 

 tidligere beskrevet, benytte dennes Navn. 



Det er ellers i Regelen yderst vanskeligt, for ikke at 

 sige umuligt. at kunne henføre noget af de undersøgte Dyr 

 til en allerede beskreven Form. speeielt gjælder dette de 

 af Bowerbank beskrevne; indenfor den samme Slægt fore- 

 kommer hos ham saa forskjellige Kiselnaaleformer. og 

 samme Naaleformer rindes hos forskjellige Slægter. saa det 

 bliver aldeles umuligt efter Naaleformerne alene at finde 

 frem i Bowerbanks System. Og heller ikke er Bowerbanks 

 øvrige Karakteristik af Slægterne af den Beskaffenhed, at 

 man kan tinde sig tilrette ved Hjælp af samme, og jeg 

 har derfor ganske maattet opgive at finde Rede i Bower- 

 banks System. Om to Svampe har sine ens spids-spidse 

 N~aale ens anordnede, men der hos den ene af dem til 

 disse Naale kommer en anden Sort. saa bliver det et 

 Sporgsmaal. om Anordningen eller Naaleformerne skal an- 

 sees som det væsentligste til at karakterisere Slægten, og 



IJen norske Nordhavsexpedition. ". A. Hanssen: Spongiadæ. 



All of the sponges wen' preserved in alchohol; a small 

 number of them were shrunk, however, owing to the 

 incomplete closing of the vessel that contained them, and 

 consequent evaporation of the alchohol. The superscrip- 

 tion on a large number of the distinguishing labels 

 had been effected with Aniline ink, and these labels 

 show, now, no trace of superscription, although several 

 means have, subsequently, been attempted, in vain, to 

 recall the writing. In consequence of this, it has become 

 impossible, now, to state the habitat of a large number of 

 the sponges. 



Although, upon the whole, the sponges have been 

 well preserved, it has not been possible, for me, to obtain 

 preparations from a single one of them, in which I could 

 trace out the canal system or, generally, the structure of 

 the soft parts. The only definite feature, therefore, for 

 the discrimination of the sponges, has been the form and 

 arrangement of the siliceous .spicules. As is known, the 

 external form of these animals gives, in only quite a few 

 cases, more or less trustworthy distinguishing characteristics. 

 Upon the other hand, the form and arrangement of the 

 siliceous spicules appear as if they might be used as a 

 basis for a systematic classification. The number of sponges 

 treated of in this report is too small, however, to establish 

 a system upon, and I confine myself, therefore, to arranging 

 the material according to the form of the siliceous spicules. 

 and where it has been possible, for me, to identify a form 

 with one already previously described. I will make use of 

 the designation of that one. 



It is, usually, however, extremely difficult, if not absol- 

 utely impossible, to assign any of the animals investigated, 

 to a. form previously described, and this is specially the 

 case in regard to those described by Bowerbank. In his 

 works we meet, included in the same genus, such divergent 

 forms of spicules; whilst, also, we find the same spicular 

 form in different genera ; that it becomes quite impossible 

 to trace out a path in Bowerbank's system, solely, by the 

 spicular form. Neither are Bowerbank's other generic 

 characteristics of such a nature, that we can see our way 

 by the aid they afford, and I have, therefore, been obliged 

 to relinquish the hope of assistance from Bowerbank's 

 system. When two sponges have their uniform acuate spic- 

 ules similarly disposed, and when to these spicules there 

 is, in one of them, added, also, another kind, it becomes, 

 then, a question, whether the disposition of the spicules, or 



l 



