D< 



'en samling af Ascidier, som forelaa fra den norske 

 !Nordhavsexpedition, blev mig i høsten 1894 overladt til 

 undersøgelse, og samtidig fik jeg til afbenyttelse nogle teg- 

 ninger, udførte af professor G. 0. Sårs efter levende indi- 

 vider. Jeg tillader mig herved at bringe Nordhavsexpedi- 

 tionens redaktionskomite, professorerne H. Moini og G. 0. 

 Sårs, min tak, fordi dette interessante materiale er bleven 

 mig overladt. 



I to andre afhandlinger i samme bind har Kiær og 

 Huitfeldt redegjort for de tidligere arbeider, som berører 

 Norges ascidier, og jeg finder det overflødigt her atter at 

 gjentage dette. For de arters vedkommende, som allerede 

 er beskrevne af Kiær eller Huitfeldt i en af de nævnte 

 afhandlinger. slutter jeg mig ogsaa til dem baade hvad be- 

 skrivelse, synonymi og literatnr angaar. 



Ved bestemmelsen af arterne iiar jeg rettet mig efter 

 Herdmans systematiske fremstilling. 



Det materiale af ascidier, som forelaa til undersøgelse, 

 bestod af 11 forskjellige arter af enkelte ascidier og 10 

 arter af sammensatte. Men flere af dem er desværre ikke 

 saa vel konserveret, at det er muligt at foretage nogen 

 nøiagtig undersøgelse af deres anatomi, og da der kun for 

 nogle enkeltes vedkommende medfølger tegninger efter de 

 levende individer eller kolonier, har jeg heller ikke kunnet 

 benytte farven som ledetraad ved bestemmelsen. Endelig 

 fandtes af de fleste kun et enkelt exemplar, og saaledes 

 har undersogelsen, især af Synascidierno men ogsaa af et 

 par af de enkle, havt sine vanskeligheder, og jeg er af den 

 grund nodt til at lade et par arter staa som usikre. 



T, 



ne coUection of Aseidire resulting from the Nor- 

 wegian North Atlantic Expedition, was submitted to me 

 in the autumn of 1894 for examination. and at the samt- 

 time I was permitted to make use of some drawings exe- 

 cuted by Prof G. 0. Sårs from living specimens. I ven- 

 ture here to express my thaiiks to the editing committee 

 of the Norwegian North Atlantic Ex|>edition. Prof H. Mohn 

 and Prof G. 0. Sårs, for having submitted this interesting 

 material to my inspection. 



In two other pajiers in this number, Messrs Kiær 

 and Huitfeldt give an account of the earlier works which 

 touch on the snbject of Norwegian Ascidiæ, and I tliere- 

 fore consider it superfluous to rejjeat this here. ^\'ith 

 regard to those species which have already been described 

 by Kiær or Huitfeldt in one or other of the above-named 

 • papers, I agree with them, as regards description, synonyma 

 and bibliography. 



In deterraining the species, I have followed Herdman's 

 systematic classification. 



The material to be examined consisted of 1 1 different 

 species of Simple Ascidians and 10 species of Compound 

 Ascidians. Several of them, however. are unfortunately not 

 in a sufficiently good state of preservation to allow of tiie 

 possibility of any minute examination of their anatomy, and 

 as only a few are accompanied by drawings from living 

 specimens or colonies, I have not been able to make use 

 of the colour as a clue to their determination. Lastly, of 

 most of the species there was only a single speeimen, and 

 thus the examination of two or three of the simple si)ecies, 

 hut especially of the Synascidiæ, lias been attended with 

 difficulty, and for this reason I am obliged to leave a few 

 of the species undetermined. 



Den norske NortUiavsexpedition. Kristine Bonnevie: Ascidiæ simplices og ascidiæ compositæ. 



