ME. P. H. CARPENTER ON THE GENUS ACTINOMETRA. 11 



usually large specimen of the Comatula Solaris of Lamarck — unfortunately, however, 

 only a dry one, which he found to differ so greatly from the other Comatulce then known 

 to him, that he described it under the name of Actlnometra imperialis \ " welche gene- 

 risch von andern durch die Bildung ihres Scheitels verschieden zu sein schien. Auf 

 dem Scheitel der mit hlumenartigen Kalkhlattchen bedeckt ist, ist keine Spur von den 

 Furcken zu sehen, die bei den Comatulen von den Arm en zum Munde fiihren. Auch ist 

 dort nichts vom Munde zu sehen. Die Mitte der Bauchseite nimmt eine Ptohre ein. 

 Die Arme haben die ventrale Furche der Comatulen, die Furchen der zehn Arme miinden 

 aber in gleichen Abstanden in eine die Scheibe am Rande umziehende Cirkelfurche. 

 Diese eigenthumliche Bildung Hesse sich durch eine unsymmetrischc Vergrosserung 

 desjenigen Intertentacularfeldes, worin die Afterrohre steht, iiber den ganzen Scheitel 

 unci auf Kosten der anderen Intertcntacularfelder erklaren, so dass der Mund aus der 

 Mitte des Scheitels ganz an die Seite zwischen je zwei Armen gerath ; es ist mir aber 

 nicht gelungen den Mund hier zu finden." (PL I. fig. 2.) 



In a subsequent visit to Lund, Muller examined two dry specimens of Comatulce, which 

 had been described by Eetzius 2 many years previously under the names of Asterias pec- 

 tlnata 3 and Asterias multlradlata. These he found to belong to the same type as the 

 Vienna specimen, which he had already designated Actlnometra imperialis, and which 

 he supposed to be distinct from the true Comatula Solaris of Lamarck. When he visited 

 Paris, however, in 1844, he examined Lamarck's original specimen of this species, and 

 convinced himself of its specific identity with his Vienna Actlnometra. Consequently he 

 withdrew the specific name "imperialis," and described the type simply as Actlnometra 

 solaris\ Muller was unable to determine the position of the mouth in the dry specimens 

 of the Lund aud Vienna Museums on which he founded his new genus Actlnometra; but 

 subsequently he was able to examine many spirit-specimens both of his typical species, 

 Act. Solaris, and also of other " Comatulen von jener Anordnung der Purchen, sowohl 



zehnarmige als vielarmige Siehe die beistehende Pigur von Comatula JFahl- 



berghil 6 " (PL I. fig. 3). This last species he describes a few pages further on as Coma- 

 tula (Actlnometra) JVahlberghll. 



He did not, however, appear to regard the position of the mouth as of any systematic 

 importance ; for he goes on to say : — " Der Mund ist bei der in Frage stehenden Ab- 



1 Wiegm. Archiv, 1841, i. p. 141 ; and " Neuo Beitr. z. [Eenntniss der Arten der G'omutalen," Wiegm. Archiv, 

 1843, i. p. 132. 



2 Dissertatio sistens species cognitas Astcriarum. Lundas, 1805. 



3 The specific name " peetinata" Linnasus, included both Retzius's specimens and the Decacnemus of Linck. 

 These belong, however, to two very different types of the genus Comatula, and must be carefully distinguished from 

 one another. The former is, as above mentioned, an Actinometra, while the latter was called Ahcto by Jfuller, 

 being simply the common Comatula mediterranea, Lam. Pennant, Adams, and others naturally employed the 

 Linnean name for this last species ; but Dujardin, following Eetzius and Muller, applied it also to Retzius's original 

 specimen, which is really an Actinometra, and not an Antedon, like C. mediterranea. This has given rise to much 

 confusion in the synonymy of these two species. 



4 Wiegiminn's Archiv, 1843, i. p. 133. ° ' Gattung Comatula,' pp. 12, 13. 

 6 Ibid. p. 9. 



