36 McMURRICH 



Genus Anthopleura Duch. & Mich. 



Synonyms. — Aulactinia, Verrill, 1 864. 

 .'Egeon, Gosse, 1865. 

 Bunodosoma, Verrill, 1899. 



Cribrinidai with true acrorhagi, usually with numerous per- 

 fect mesenteries, sphincter strong, column destitute of an epi- 

 dermal covering and provided with verrucae arranged more or 

 less definitely in vertical series, tentacles simple. 



5. Anthopleura xanthograininica (Brandt) 



Synonym. — Actinia (Taractostephanus) xanthogrammica, Brandt, 1835, 



This species was found in only one locality, under the slaughter 

 house at Port Townsend, but it occurred there in large num- 

 bers. An excellent figure of it is among the drawings kindly 

 lent me by ^Ir. Agassiz, the individual figured having been ob- 

 tained at San Francisco. Dr. Calkins states that evidences of 

 multiplication by fission w^ere not unfrequent among the Port 

 Townsend specimens. 



External Form. — The base is adherent. The column (PI. II, 

 Fig. 17) is provided with rows of tuberculiform verrucae, to 

 which particles of sand and small stones adhere and which are 

 arranged in distinct vertical rows extending to the limbus as a 

 rule, though in the upper part of the column shorter rows alter- 

 nate with the longer ones. The margin is separated by a dis- 

 tinct though shallow fosse from the bases of the outermost ten- 

 tacles, and from the margin of the outer wall of the fosse there 

 project blunt processes, one of which corresponds to the summit 

 of each row of verrucae (Fig. 19, a, r). These are undoubtedly 

 acrorhagi. They are much more distinct in some of the pre- 

 served individuals than in others and, indeed, may be more 

 prominent at one portion of the margin than at another in the 

 same individual, here appearing as mere hemispherical elevations 

 and there as distinct blunt tentaculiform projections, or again 

 having a distinctly lobed form. 



The tentacles in the preserved specimens are very moderate 

 in length, conical and rather obtusely pointed. In Mr. Agassiz's 

 drawing they are represented however as rather long and slender, 



