202 ACTINLi: OF ALI{ATIU)SS EM'hi >K'A I'lDNS M'MnUKUll. 



36. Ceiianthus vas, sp. nov. 

 IM. x\xn. l'ij;N. 117-li;i; I'l. \\\\, Im^. I'JO. 



No. 726. Station L'S;>S. l,.il.l.'S IL' N. ; loiiji. 1 ir>();t W. l>.])lli, 1 1 fatlioms. Oiio 

 H|)('('iincn. 



The sin^lo Ocritviitlii«l whicli 1 louiul in tlio coUoction p:avo so nmcli 

 proiiii.^c of intciTstiiii;' icsiills tlcil 1 (IclcniiiiuHl lo sacriCico it f,o nil 

 ;iii;il(>iiii«';il in\ est ipit ion. Unlorhmatolv, however, it did not provo to 

 be well ])rosorve(l, and many ]>oinls on which I had hoped to»»hlain 

 definite intonnation n'niained ohsenre, partly owinj^' lo i\\r presei\ ation 

 and partly to the dilhenlties in the way'ol' obtaining all the. necessary 

 datai from a single specimen. .\ portion of the np|»er part I cut ill 

 loniiitudinal sections in the «'ndea\oi' to obtain, if p<»ssible, delinito in- 

 formation as to the absence of tentacles, an<l was thns prevented from 

 makinji" a thoronuh stndy of the arrangement of the mesenteries. 



The specinuMi (IM. XWIV, l-'i^-. 117) measured '_*.()"". in hMiyth ami 

 about 0.1)"". in dianietei', and had a decided \asc JilvC appeaiam-e. 

 The margin was sliiihtly reliccted, and there w as a «list inct neck like 

 constriction a little below it. Tlu' cttlnmn was cylindiical, tapering' 

 liradually below, where there was a lai.Lic widely open pore commnni- 

 catini;' with the interior ca\ity. The ectoderm had a pale brown color, 

 and its mnscidatnre was richly dcNcloped in the manner characteristic 

 of the ('crianthidie. 



N(» tnbe ac«'ompani(^d the specimen, nor ha\'e 1 any information as to 

 whether ther*' was one when it was t'oniul. 



A remarkable pccnliarily which attracted my att«Mdion at om-e was 

 the apparent absence (d' tentacles. Neither at the maruin noi' npon t he 

 disc coid<l any of these strnctnr«'s be found. It is ]>ossibIe that tln'y 

 may have fallen away, an idea to which the fact that any sections 

 Ihrouuh the margin did not show coidinnily of \\\v colnmn wall and 

 «lisc, except in one or two cases, <iives su])])ort. It seems hardly possi- 

 ble, how»'\t'r, that if they had been preseid t hey eonid ha\ e disai>|)eai'e(l 

 so c(»mpletely as t hey seem to have (loiM', and 1 am rather inclined to 

 bclicxc that they were absent or reduced to nu're rudiments. 



The stomatoda'um was narrow, extendinu" oidy a short distance into 

 the interior cavity, 'I'he portion which I used for lonj>itiulinal sections 

 proliably contaiui'd the siplnuioulyphe. I'pon the other sid«' of the 

 stomat«)da'nm lu) sii)h(>nonlyph(> occurred. 



In a sectiim thronuh the noddle of the column (Tl, wxv, I'Mu. 11*0) 

 twenty-two nu'senterics <'onld l>e «"onnted. They sh(tw«'(l a teudeney to 

 be arrauiicd so that broad and narrow mesenteries should alternate 

 with <me another, but this arrauji'cment was fretpn'utly marred by a 

 broad mesenl(>ry occnrrinu in thephn-eofa narrow on»>,and vice\ersa. 

 It is eviib'nt, howcN'cr, that two yrades ot' mesenteries are represented 

 in the section, one consist iuii' of about twelve mcsenteri(\s (piite wide 

 and bearing ri'prodiM'ti\o orgaus as a ruh', and one whose mesenteries 



