736 



MR. J. P, MCMURRICH ON THE SYSTEMATIC 



the shore at the station, again well above low-water mark, so 

 that they remained exposed to the air for several hovirs at each 

 tide. I am confident that they did not occur on these rocks in 

 the earlier years; had they then secured foothold upon them 

 they could hardly have escaped observation. The rock on Jesse 

 Island is not far from the station, but their extension to the 

 latter locality is of interest in connection with the migrations of 

 jS. htcice on the New England coast and at Plymouth. Many 

 years ago Mr. Alexander Agassiz gave me a number of drawings 

 of Actinians that he had collected in the Gulf of Georgia in 1859, 

 and among these there were two that were unmistakably 

 representations of the form under consideration. The drawings 

 were made from specimens collected on Galliano Island, and 

 furnish certain proof that the form has been in existence on the 

 Canadian Pacific coast for over sixty years at least. 



Diagrams showing the arrangement of the mesenteries in three individuals 

 from Departure Bay, British Columbia. 



As has been stated, these Pacific forms resemble aS'. lucice in 

 their external form and coloration ; their anatomical structure is 

 also the same. They shoAv a similar fosse, complete absence of a 

 sphincter, and a similar ari'angement of the mesenteries. The 

 iri-egularities of the mesenteries were not so marked as in the 

 Plymouth examples, but were nevertheless quite evident, as may be 

 seen from the diagrams (text-fig. 4), which represent the arrange- 

 ment observed in three individuals. In each case the individual 

 was monoglyphic, with but a single pair of directives, and in one 

 case there were only four pairs of perfect mesenteries, in the 

 other two five pairs. Two cycles of imperfect and fertile 

 mesenteries were present, in one case arranged symmetrically 

 with regard to the four perfect pairs, but in the others showing- 

 some irregularity, and in the example with four pairs of perfect 

 .mesenteries representatives of a third imperfect cycle, without 

 mesenterial filaments or reproductive elements, occurred in two 

 of the interspaces. Acontia were present, but not abundant. 



There can be no doubt as to the specific identity of the 



