1I>2 ACTINI.K OK Al;l?.VTi;OSS EXPliOUATlONS M'MUKKUJll. 



siplioiioiilypluvs aio, liowovcr, not piiiinnitcd, ;iimI constMnuMilly arc 

 very iiodccabli* whoii tlu> animal is opciUMl lon;^itU(liiiaIIy. 



Tliori^ are lour < ytlos of iiu'sont cries, of whirli the i>riniary cycle is 

 alone prrli'ct, ami a( tlie sanu^ time sterile; the fourth cycle mesente- 

 ries are small and are not .nonophoiic, tlu^ reproductive elements de- 

 velopinii' oidy in the mesenteries of the second and third cycles. The 

 lon.uitndinal nuiscnlature is Avell developed (IM. xwii, Fij;-. 10L»), but 

 can hardly betcrmcd ''Very stronji." The])ennon is not wide, the muscle 

 processes arisinj;' in bunches from one to three stout elevations of the 

 mesojjhea; it is much more marked in the upper portions of the meseii 

 ttnics than it is h)\ver (b)wn, where it becomes U)wer and at the same 

 time broader. 1 did not observe any extensive folding- of the trans- 

 verse muscles, nor could 1 find in sections any ]»arieto basilar muscle. 

 Acontia are present, lying in buiu'hes in the lower portion of the inter- 

 nal cavity. 



1 identify this form with llertwiji's riuilia spiniftra, with which it 

 ajirees closely. 1 have, however, accepted the possibility which llert- 

 wij^- sujijiests, that his F. spini/cra may be a variety of his J*, ptrtinata, 

 described in his lirst report ('Si'). The dissimilarity in the arrange- 

 ment of the tubercles in the two forms is to a certain extent, as he re- 

 marks, bridged over by the specimen obtained from station .'>L*(), and 

 the second and third Allxdro.ss spcciniens help to bring the two forms 

 inl(> closer connection. If the ditVerence in the nature of the disc nuis- 

 cnlature in the two forms holds throughout, it may be necessary to con- 

 sider them distinct, but since in all other i>artiiulars they shade into 

 each other so closely, I think it better to consider them for the present 

 identical. 



Gouiis STEPHANACTIS, lltrtwij,'. 



Chondractinina' in which the l)ody is elongated in the transverse 

 axis, the base inclosing a cylindrical body, such as an Alcyonaiian 

 stem; column with thick wall, but not covered by a mcH marked 

 cuticle; capitnlum smooth, sepaiatcd from the smooth seajjus by a 

 well marked circular swelling. 



In his report on th(> Acliniaria, obtained by the ChaUcniicy, iiertwig 

 ('SJ) established afamily Amphianthida> for two genera . I »//>// m»///M.s' 

 and SttpliaiKnl is, hoWx of which were characterized by the body being 

 transversely el(>ngated, the base clasping and inclosing the stem of a 

 (iorgonia. From his observations (Ui l!<t(j>han(ic(i>i ti(hini(lat<i he found 

 that in the arrangement t>f the nu'sentcries, and in the presence of a 

 sphincter muscle imbedd«'«l in the mesoghea, there was a great similar 

 ily to a Sagarti«l, but he faiU'd to discover acontia, altliough cincli<lal 

 oi>enings pierced the column wall. Previ«msly to llertwig's discovery 

 «»f these forms, von Koch ('78) had described an Actinian, adherent 

 to and embracing by its base the stem of Isis chutjdta, and in this he 

 fancied he had found a clue to the ancestry of the Antipatharia. This 



