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IX. On the Actinkm Buuocleopsis globulifeva, Ven'ill. By J. E. Duerden', Pli.D., 

 A.It.C.Sc.{Lond.)., Bruce Fellow, Johns Hopkins TJaiversity. {^Communicated by 

 Prof. G. B. HoAVES, F.B.S., Sec. Linn. Soc.) 



(Plates 25 & 26.) 



Read L'Oth rebruary, 1902. 



In a preliminary paper on the Jamaica Actiniaria (1898) I briefly descril^ecl a new West 

 Indian Bunodeopsis, without assigning it any specific name. The year previous I had 

 given a fuller account of two other species of the same genus, and it was intended to 

 institute a comparison with these. In 1899, Prof. A. E. Verrill figured, without any 

 comment in the text, a Bermudas Anemone which he identified as the Viatrix (jlohuli- 

 fera of Duchassaing and Michelotti (1860). Upon the appearance of the paper I drew 

 Prof. Verrill's attention to the similarity between his drawing and the new Bunodeopsis 

 which I had obtained, and the year following appeared his description of the form as a 

 new species, Bunodeojisis globulifera. The description is limited, however, to an 

 account of the excernal characters, and gives no attention to the peculiarities of 

 anatomy and minute sti'ucture. 



A study of the internal structure and histology of the two species of Bunodeopsis in 

 1897 had revealed the presence of a well-developed ectodermal muscle and nerve-layer 

 on the column- wall, along with several other exceptional features, Avhose significance 

 was not then realized. About this time Dr. Oskar Carlgren (1893, 1900) was directino- 

 attention to the importance in Actiuian phylogeny of the occurrence of an ectodermal 

 columnar musculature, and its usual association with the absence of gonidial grooves in 

 the stomodseum, absence of ciliated bands from the mesenterial filaments, the non- 

 development of the basilar muscles, and the occurrence generally of a weak internal 

 musculature. Every species of Bunodeopsis thus becomes of special interest in 

 connection with this latest jihase of the morphological study of the Actinians. 



The genus Bunodeopsis has been thus defined by me (1897, p. 6) : — " Tissues very 

 delicate. Tentacles elongate, readily retractile. Column short, beset proximally with 

 pedunculate or sessile vesicles, the vesicular area much broader than the capitulum. 

 Sphincter muscle feebly developed. More than six pairs of perfect mesenteries." 



The genus at present is included within the family Aliciidae, which in the same paper 

 (p. 2) is characterized as follows : — " Ilexactineoe with a large, flat, contractile base. 

 Tentacles simple, subulate, and entacmseous. Column with simple or compound 

 outgrowths or vesicles over more or less of its surface, arranged mostly in vertical rows. 

 No cinclides. Sphincter muscle endodermal and diffuse, variable in amount of 

 development. Perfect mesenteries few or numerous. No acontia." In addition to 



SECOND SERIES. — ZOOLOGY, VOL. VIII. 4-J, 



