"_'C)8 COXTEIBUTIOXS TO CAXADIAX PAL/EONTOLOOY. 



Ari'i-riiJdriJi- Dnvii/sdii.i and Ari'rr. jirofiinda, whicli latter," lie ccMisidei'.s 

 "merely as a variety of the former, are in structure identical with Gya- 

 tli()j)hiill iiiii nij/iis/un." "The genus Ai-iin:iilriri.<i. is i'c])i'e,s(!nted as having 

 its central portion of the polyp cells suri'ounded by an internal wall, but 

 neither the a))ove-mentioned corals nor the typical foi'ms of the genus 

 Ai-i'i-riil(iri(i {C i/dtli. jiciitagoniiin and (jyiitli.. (iiiiiiKisoi (hildfuss) exhiljit 

 an internal wall. In the circumference of tlieabrupt inner cell-iiits of all 

 tliese fiii'ms a sort of annular demarkation is conspicuous in transverse 

 si-cti(jns, because the shorter ones of the alternately laigei' and smaller 

 i-adial lanielhe terminate there M'ith somewhat thickened edges, l)ut thev 

 nevei' combine into a closed, i-iug-like wall." While following T)r. liominger 

 in regarding Aci'i-riiJnn<i jn'ofinir/n as a (Ji/iiflii>ji/ii///ii in, and Di'. Freeh, 

 who has seen the specimens collected by ^Messrs. Tyrrell and i)owling, in 

 reterring them to the groupi of '_'. Iip.iYii/ninnii, it is thought desirable to 

 retain Hall's specific name for these specimens, as they correspond much 

 better with his description and figures of ^1. pr<ifini.(/(i, than with those of 

 A. Dii rif-/s<iiii. 



CyATIIOPIIYLLL'M PEOFUXDUiM. (Va.i.) 

 I'late .34, figs. 4 mikI 4ii. 



Coi'allum large, composite, massive, in the only syx-cimen kjiown to tli(^ 

 writer d(!pressrd subsph:erical : corallites polygonal oi- rounded polygonal, 

 intimately united thi'oughout their length, and sejiara.ted only by a single 

 and extremely thin wall, unequal in size, the adult ones averaging froni 

 seventeen to nineteen millimetres in their maximum dia.nieter. (Jalyces 

 shallowly concaseexternally, the abruptly and not very deeply e\ca\'ated 

 central portion occupyiiig rather mcjre than one half of the entire diame- 

 ter of each c(j]-allite ; septa as many as fifty foui' in luindier in the la.igest 

 corallit(.'S ; at the bottom of the cup and below it many cjf tlje septa I'e.'ich 

 to llie centre, the others being shoiter but very uneipial in length. Inter- 

 jia,l structure, as shown in loiigitudinal sections, eonsisting of line \-esicu- 

 lar tissue between the septa, their being no tabuhe nor a.rehed carina'. 



Si.)iith end of Snake Island, L^d■:e Winnipegosis, J. I!. I'yrrell, ISSi) : ii 

 single colony, about six inches in length, live in breadth and two and a 

 half in height, a portion of which is ligured. The specimen seeiris to indi- 

 (•a,te or repi'eseiit a local variety (jf C. jn-aj'ii in/inii, in which the adult 

 eiii'allites are larger, their septa more numerous and the interseptal \-esicles 

 proportionately smaller and mcjre numerous than those of the typical form. 

 l)r. I''i-eeh thinks that the specimen is very nearly related to the ('. /iij/io- 

 crd/fri./iiniir of fjoldfuss. 



