''"i;;!)^''] PROCEEDINGS OF THE NATIONAL MUSEUM. 123 



wards,* wiio divickMl liis group of the, Polypes parenchyma k's into tliree 



groups : 



Sortiilaiii'118. Zojinthairos. 



Alcyoiiiciis. 



Oftliese tlie first group corresponds to the Hydroidea, the second to 

 the Actiniaria and Ilexacorallia, and the hist to the Ah'yonaria. 



A most imi)<)rtant classiiica-tion api)eare(l in 184(1 as tlie result of the 

 extended study of the Zoiiphytes of the Wilkes exploring expcdilion 

 by Prof. -lanu's 1). Dana, Ilis groups are as follows: 



/.or>l'IIYTA. 



I. Order. Acl inoidia. 



I. Siilxn'tU'r. .Vi'tiuaria. 



I. Tiilx'. Asti'a'ac(!a — incliidiiiji; thi^ A(!tiiiiaiis with which Liiccrnaria was 



associated and tlic Astreid and Fiiii.i:;id corals. 



II. Tiibc. (!arvo])hyllac(^a—ill(•lMdinl;• besides the Caryoiiliyllids andCyatho- 



idiyllids, tlic Zoanthea". 



III. Tribe. Madreporacea — iiiciiidiiij;- Madrcjiorids, Kavositids, to which are 

 referred tiio Milh'pores and i'oiitids. 



IV. Tribe. Antipathacca. 



II. Sul>order. Alcyonaria. 



II. Order. Hydroidea. 



It will be seen fr<»m this that the orch-r Actinoidea. is ])i'a('tieally 

 erpiivalent to the grou)) Anlhozoa- of today, and that a clear distinc- 

 tion is made between the Actiniaria. and the Alcyonaria. The fornu'r 

 group includes all the Ilexacorallia and the Actiniaria of later authors, 

 as well as the Antipathacca, and it is interesting to note that Dana in- 

 sists npon the unimportaiK^' of the stony corallum, grouping together, 

 as De lUainville had done before; him, the nou-skelel<>gein)us Actinians 

 and the skeletogenous Ilexacorallia. 



Oiu' of the y)riiH'ii»al grou])s of the Anthozoa, the Alcyonaria, being 

 thus delimited, and a second, the Antipatharia, alsonnu'ked out, though 

 not considere<I of e(pnil value, it will be well to go back some distance and 

 note tin; gradual discoveiy of various forms recognized now as distinct 

 groups, but included so far as known in the fust two tribes of Dana's 

 Actiuaria. 



The earlier authors recognized a single genus oi Aciiiiiu only, though 

 other names, — e. //,. (^rtiai, Hijiiro, and I'riKpKs — had been proposed. 

 In 1801 Lamarck separated the genus Z<K(nflius for tJie form described 

 by Ellis as Acdnid sociafd, aiul thus paved the way for the distinction 

 which later authors nuule between this and similar forms and the 

 Actinia' proper. Cuvier also iccognizcd the genus Mun/as, referring 

 it, however, to the Holothnrians, its true position not being recognized 

 until later by Lesueur ('17). A further division of the genus Actinia 

 was inaugurated by Okeu in lSir», who est d)lished the genera Metrid- 

 ium and Cereiis, and set the example for the more accurate generic 



*I take this stateineut from Daua, not having access to Milue Edwards' work. 



