23. HELIOPIIYLLUM EXH.I ;r.\i (Billings). 



Hellophyllum exiijnuia( Billings), (,'<!/;<?//" J<nu-. New Series, Vol. V. p. 201. Fi::s. 9 

 & 10. 



" Small, turbinate, more or less curved, often flattened on the side of the convex curva- 

 ture ; radiating septa between sixty and ei-hty ; about MX ..b-eure arched -tiia- to one line 

 on their flat sides, and the same number of -pines on their edtres. The depth of the cup is 

 equal to one fourth or one third of the whole length of the coral. In small specimens, the 

 mar<_ r in of the cup is thin and sharp ; but in lame MI. - muml. d. and one line or a little inure 

 in width. About one half of the radiating .-epta r.-.a-h the c> ntre, and form a small muu 

 elevation on the bottom of the cup. There is a septal f'o-.-ette on one side, which, in all the 

 specimens I have seen, reach'-s the centre. The surface exhibit- a few sharp constriction - 

 grow th. with rounded annulations between them, tin' latter often abruptly terminated OD their 

 upper sides. In very ; -linen-, line encircling striae of variable >i/e. apparently from 



ei"ht to fifteen in the width of one line. The horizontal stria), whu-h indicate tin- number of 

 aepta, are distinctly visible but not strongly marked. The p"-i:ion of the septal foffl 

 indicated on the outside of the cup by two septal ridges which extend the whole length of the 

 1, and constitute one of the lines aloiiLT which the younger -epta were added 1'rom lime to 

 time. 



The irreater number of the specimens are from >i\- to nine lines in length, but some are 

 full one inch. The width of the cup i< always a litrle less th m th len-th of the entire li,-.-il. 

 The most common number of septa is sixty. The arched strut- and -pines are nut often pro- 

 s:rve 1 " ( Billings). 



I have been tlius p irti'-ular in i|Uotin_' the de-eri ;ven hy .Mr. llillin--; of tliis 



species at full length, as in studying it, I have met wiih -real difficulties, wliieli I cannot \et 

 entirely explain. The few exatnples whieh 1 i.-olle.'t.-d at Rama's l-'.-u-m, 1'ort ( 'olhorne. itlie 

 locality ^iven >jy Mr. Billin-.- .. th ( 1 should b" di^po-ed to refer to this -p. Tie-, exhihi' only 

 the form of the oorallum, tip- epitheea, and th<' edje of the e ml the characters oftl 



are Hlln'ei.'iitly distiln-ti ..-. - i :ar at any rate, a- tin- other Canadian speeies of // in 



are con,-erned. The coral is -in il and turhinate. aiel i- di.-tinetK tl ittened alon- its con 

 curvature; the epitheea is thick and continuous, and i- thr w i into strong encij cling rid 



and annulations of <_ r rowth. tlie vertical line- indieat in- the >epta heinir very fiintiy mark, d, 

 an 1 the --jita are alternately 1 ir-e and small, and are not denticulated on their tla' 

 One } ;.eeimen only >V\^. 'ij hive | obtained. >howini_ r all the internal eharae 



from the ('-rnii'-rous Lime-tone ,,)' 1 | ij.T>ville ; and thi- shows eonelu-i vely the di-'ineti 



of II. .</<""/' as a separate specie: ofHeh / um. 'l'bi> -pe.-imen is small, turbinate, \\ith 



a con-trieted pedunculate base, the lonje-t side being tlitt.ned. Tlie total l.-n-tli alon- the 

 lon-e-t -id. lit line-,, nu the >borte-t >ide foiii- li diameter of the ealiee I,,. 111.4 



seven lines. The ealiee i> di-tiuetlv i|iiadraiiL:ular, moderately deep, with thickened mar_ins, 

 and a vi-rv well marl.i-d -,-pt d fosette. Tin- -ept'i :,! I'eiir in number. alt.Tiiat. 



and -m ill, with about live arched Striae OH their 11 it -ide, and tin- .-ame number ,.f >lmrt .-pine? 

 On their edges. The >--ptal lo--ule conv-pou.1- witM t\v > primary .-epta, which extend the 



who).- length of the corah and from the t\\ .. of which the other septa diverge ; a peon* 



liariiv which I have failed to ub-,-rve in ill-- examples from I Q6. Thecpiti 



ptal ,-tri. . and ein-ii eiin- annulations of growth. 



ompany ing the specimens of A Hill- 



iir_ r -i. at I'oi t t 'oliiortie. 1 h:.\e f. iiimla l:ir_ r e nnmlier of 



t men- wi ich ome striking characters with 



// ./-///I. but which differ from this in oilier 



char and that to ,-uch an c\!cnt 



that I do II" . b.' referred to the -emi 



II. ;/>/! <///iiiii at all, se.-miii- rather to b : . the 



-mil - / 'I'll-- di-crep incie, offl "ii indi- 



Oated le ! | ,]o !,> pret.-n.i but I shall 



1 -' fl - provi-ion dlv de-eribe the specimens in question a- div 



li ' l-'i'l-nn rzi : r"im (I'.illr tllict. under lie name tif ; . 'HI. 



'r.- I . . . u( III-: 



Ooi ' . 



