274 

 6. „Branchlocerianthus" a Correction K fgl'.es b!^' 



By E. L. Mark. 



eingeg. 15. Mai 1899. 



The description of a supposed new genus of Actinians, yyBran- 

 chiocerianthus a , published last summer 2^ was based on external ana- 

 tomy. An examination of sections from several individuals which have 

 been prepared during the winter has, much to my surprise, revealed 

 no trace of the radial partitions which the external appearance of the 

 animal led me to suppose existed. In another point, too, I was unfor- 

 tunately hasty. I at first imagined that the peculiar organs surround- 

 ing the oral proboscis were reproductive in function, and consequently 

 made sections of them from an individual to ascertain if that opinion 

 were correct, but found the organs destitute of sexual products. This 

 fact, together with the uniform, or gradually diminishing, calibre of 

 the branches in the case of an individual which was dissected out 

 with some care led me to reject the idea of their sexual character. 

 It turns out, however, on examination of sections from other indivi- 

 duals that these are really sexual organs. 



It results from all of these errors of mine that I have needlessly 

 burdened the literature of Zoology with a new name, which no one 

 can regret more than I, though I believe that the description given is 

 fairly accurate as far as it goes. 



It is clear from what I have said that the animal in question 

 must be more nearly related to the Hydroidea than to the ActÌ7iìa^ 

 though its exact affinities I have not yet determined. 



1 may add that a similar, though much larger animal has been 

 recently dredged off Misaki in about 300 fathoms by my friend Pro- 

 fessor Mitsukuri of the University of Tokyo. 



Zürich, March 25, 1899. 



P.S. Since writing the above, and while waiting for an opportu- 

 nity to settle more definitely the relations of this animal, I have received 

 from Professor Mitsukuri a letter in which he says that he has 

 come to the conclusion that the animal dredged by him is not an 

 Actinian, but is allied to the Tubularian Hydroids, and that possibly 

 it is the same thing as the Tubularian caught by the »Challenger« at 

 about the same locality and named Monocaulus imperator. Notwith- 



* Contributions from the Zoological Laboratory of the Museum of Comparative 

 Zoology at Havard College, E. L. Mark, Director, No. XCVII. 



2 Mark. E. L., Preliminary Report on BrancJiiocerianthus urceolus , a new 

 Type of Actinian. Bull. Mus. Comp. Zool. Harvard Coll. Vol. XXXII. No. 8. 

 August, 1898. 



