152 



SYS 



TILLÆG 



TIL 



GEPHYKEEBNE. 



i lmtrent et halvt Aar efterat vor Afhandling over Gephy- 

 ^reerne var afsluttet og overgivet til Trykken, *) have 

 vi modtaget 3 Arbeider over samme Dyrklasse, to af 

 Hjalmar Théel 2 ) og et af Dr. Teuscher 3 ). 



Da der i disse Afhandlinger findes enkelte Afvigelser 

 fra vore Observationer, have vi troet at burde gjøre nogle 

 Bemærkninger i den Anledning. 



Dr. Théel har dannet en ny Slægt af Phascolosoma 

 Strombi, hvilken han kalder Phascolion, og angiver som 

 Grund derfor, at den „i flere vigtige Punkter adskiller sig 

 fra Slægterne Sipunculus og Phascolosoma. " 



Allerede Keferstein har fremhævet disse Punkter, 

 men dog ikke trøstet sig til derpaa at grunde en ny Slægt, 

 idet han formener, at først naar andre nærstaaende Arter 

 ere nøiagtig kjendte, naar Exemplarer fra mange for- 

 skjellige Localiteter ere undersøgte, først da er Tiden 

 kommen til at afgjøre, hvorvidt Ph. Strombi bør danne 

 en ny Slægt eller ikke. Under vore Undersøgelser over 

 Gephyreerne have vi havt til Raadighed en stor Mang- 

 foldighed af Exemplarer af Ph. Strombi fra de forskj ei- 

 ligste Localiteter, lige fra Vadsø (Finmarken) til Christi- 

 ania. Vi vare ingenlunde fremmede for de Forskellig- 

 heder, Ph. Strombi frembød ved at sammenligne den med 

 andre Phascolosoma-Arter, hvilket forresten klart nok var 

 fremhævet af Keferstein; men jo flere Exemplarer vi un- 

 dersøgte, jo tydeligere viste det sig, at den var under- 

 kastet mange Variationer baade i det Ydre og Indre, — 

 saa vi enten af disse Varieteter maatte danne mange Ar- 

 ter — ja endog enkelte Slægter, dersom vi betragtede 

 hver Afændring for sig uden at sammenholde den med 

 andre, eller da maatte vi, som flere andre Forfattere 

 have gjort, blive staaende ved den gamle, gode Art, -- 

 og forsaavidt Afvigelserne bleve altfor store, da danne 

 særskilte Afarter. I denne vor Opfatning bleve vi end 



2 ) Indsendt til Magazin for Naturvidenskaberne i Midten af Ja- 

 nuar, 1875. 



2 ) Kecherches sur le Phascolion (Phascolosoma) Strombi, Mont. 

 par Hjalmar Théel. Communique ål'académie des sciences de Suéde 

 le 10 Février 1875. — Etudes sur les Géphyriens inermes des mers 

 de la Scandinavie, du Spitsberg et du Groenland par Hjalmar 

 Théel. Communique å l'académie des sciences de Suéde le 10 Mars 

 1875. 



3 ) Notiz über Sipunculus und Phascolosoma von Dr. R. Teu- 

 scher. Jenaische Zeitschrift für Naturwissenschaft, 8 Bd., 4 Heft 

 Pag. 488. 



APPENDIX 



T0 



THE GEPHYREÆ. 



A bout half a year after our treatise on the Gephyre£r 



was terminated and delivered to the printer l ) we re- 

 ceived 3 works on the same class of animals: 2 by Hjal- 

 mar Théel 2 ), and 1 by Dr. Teuscher 3 ). 



As in these treatises there are found a few diffe- 

 rences from our observations, we have thought it right to 

 make some remarks on the occasion. 



Dr. Théel has formed a new genus of Phascolosoma 

 Strombi, which he calls Phascolion, and gives as his rea- 

 son that „it differs in|many important points from the 

 genera Sipunculus and Phascolosoma." 



Keferstein had already noticed these points, but had 

 not ventured on the strength of them to establish a new 

 genus; being of opinion that only when other nearly re- 

 lated species are more accurately known ; when specimens 

 from many different localities shall have been examined, 

 only then will the time be come to decide how far Ph. 

 Strombi should form a new genus or not. In the course 

 of our examinations of the Gephyreæ, we have had at 

 our disposal a great variety of specimens of Ph. Strombi 

 from the most various localities, even from Vadsö (Fin- 

 mark) to Christiania; we were by no means unaware of the 

 differences which Ph. Strombi exhibited, when compared 

 with other species of Phascolosoma, which moreover 

 had been very distinctly noticed by Keferstein; but the 

 more specimens we examined, the more evident it became 

 that is was subject to many variations both external and 

 internal; so that from these varieties we must either 

 have formed many species, nay even a few genera, if we 

 had considered each variation for itself without compa- 

 ring it with others, or else we must have kept to the 

 good old species, as many other authors have done, and, 

 for as much as the differences- became too great, formed 

 separate variations. In this our conception, we were 



) Sent to the Magazin for Naturvidenskaberne in the middle 

 of January, 1875. 



2 ) Recherches sur le Phascolion (Phascolosoma) Strombi, Mont, 

 par Hjalmar Théel. Communique å l'académie des sciences de Suéde 

 le 10 Février 1875. — Etudes sur les Géphyriens inermes des mers 

 de la Scandinavie, du Spitsberg et du Groenland par Hjalmar 

 Théel. Communique å l'académie des sciences de Suéde le 10 Mars 

 1875. 



3 ) Notiz über Sipunculus und Phascolosoma von Dr. R. Teu- 

 scher. Jenaische Zeitschrift für Naturwissenschaft, 8 Bd.. 4 Heft r 

 Pag. 488. 



