REPORT OX THE HEXACTINTE 35 



endeavor to ascertain if any of the specimens collected by 

 Mertens were still in existence, but the endeavor proved futile. 



Genus Anthopleura, Duch. & Mich. 



In i860 Duchassaing & Michelotti established the genus 

 Anthopleura for a Cribrinid characterized by possessing verrucae 

 arranged in longitudinal rows and with tentaculiform acrorhagi. 

 In a later paper ('64) they added to the original single species, 

 A. Krcbsi upon which the genus was founded, other forms, one 

 of which at least possessed lobed acrorhagi, altering at the 

 same time the definition of the genus so that it became rather 

 indefinite. In 1864 Verrill established a genus Aulactinia for a 

 Cribrinid also possessing verrucse arranged in longitudinal 

 rows though becoming obsolete below and having prominent 

 acrorhagi which were distinctly lobed. The later action of 

 Duchassaing and Michelotti in including in their genus a form 

 with lobed verrucse led Verrill in 1869 to suggest the possi- 

 bility of the identity of the two genera, but Andres ('83), going 

 back to first principles, recognizes both, placing the forms with 

 simple acrorhagi in the genus Anthopleura, while those in 

 which they are distinctly lobed he refers to Aulactinia. Verrill 

 in his most recent papers ('99) considers the two genera dis- 

 tinct and adds a third Bunodosoma to which he refers the A. 

 gramdifera of Lesueur and his Buiiodcs cavcrnata, and which he 

 characterizes by possessing lobulated acrorhagi and verrucae 

 which are not adhesive. 



It does not seem to me that the simplicity or lobulation of 

 the acrorhagi is a feature worthy of generic importance when we 

 find as much general similarity in such forms as Aulactinia capi- 

 tata, Antlioplenra gramdifera and Bunodosoma cavernata^ all of 

 which forms I have had the opportunity of studying. iVs to 

 whether the adhesiveness of the verrucse may prove to be a 

 feature of generic importance, I feel more uncertain, but at pres- 

 ent am inclined to deny it that value. 



The genus ^geon described by Gosse ( '65) seems to be un- 

 doubtedly identical with Aulactinia and need not be discussed. 



I would then define the genus Anthopleura as follows : 



