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On Alcyonium pulmonis instar lobatum Ellis. 



By 

 R. Hartmeyer, Berlin. 



With one Figure in the Text. 



In the year 1755 Ellis described in his "Natural History of 

 the Corallines," as '' Alcyonium pulmonis instar lohatum," a "sea 

 production" from Whitstable, which the fishermen there had 

 brought to him under the name of " Sea-Fig." As regards the system- 

 atic position of this form, he expresses himself only in so far as to place 

 it with the Alcyonians, a group in which were united at that time, 

 along with true species of Alcyonium, Ascidians, Hydroids, Sponges and 

 even Algse. As a doubtful synonym of his species Ellis put forward 

 the Pulmo marinus of Rondelet (1555), which however has nothing 

 whatever to do with it and indeed cannot be certainly determined. 

 During the following years, Ellis' work was translated into several 

 languages. A Dutch and a French translation, both dating from the 

 year 1756, are known to me, the former by Tak, the latter by 

 A 11 am and. There is also a German translation by Kriiniz dated 1767. 



Before I proceed with the history of this species it appears to me 

 advisable first of all to define it, so as to be able in the further course 

 of the discussion to deal with a fixed systematic conception. The 

 description and the figures which Ellis gives are so characteristic that 

 the '^ Alcyonium pulmonis instar lohatum" can only be identified as a 

 compound Ascidian. As such the species was recognised, as soon as 

 ever the close relationship of the colony-forming ascidians, which had 

 previously been regarded as Alcyonians, to the simple ascidians was 

 determined, that is to say about the year 1816. It is remarkable 

 however that the form has never since been the subject of a thorough 

 description, although it is mentioned in many textbooks and handbooks, 

 as well as in faunistic papers, during the following 30 or 40 years. In 

 more recent literature the species receives scanty mention, mostly only 

 as a list name or as an uncertain species, whilst it has practically 

 entirely disappeared from the most modern literature. 



My wish to clear up if possible once for all this form by the 

 examination of typical local examples has now been carried out through 



