though it would appear that this is really identical with the previously de-cribed S.i ' 

 I<>,i<,'n*i.< of Dale Owen. Lastly a species of the genus has been recorded by Me-sra. Meek A: 

 \Vorthen, from the Lower Helderberu group of Missouri, under the name of >'. .1, 

 (Geology of Illinois, Vol. III. p. 369. Plate VII. Fig. ! 



68. STRIATOPORA LINNF.ANA (Hillings). 



>7 ma (Hillings), ' ./,,,-/,.//, New Series, Vol. V. p. 25.1. FL. 1. 



"Stems, two or three lines in diameter, branching at an angle of 75 to 80 C ; cells variable 

 in size, the greater number with the expanded mouth one line wide, and the circular cavity at 

 the bottom from oae-third to one-half of a line; the smaller or younger cell<. of all - ; 

 somewhat uniformly distributed amongst the larger. In the perfect specimens the mouth- of 

 the cells are everywhere in contact with each other, the edges of the walls between them >harp. 

 and the form more or less polygonal, generally five or six-sided. In worn specimens the 

 cells are more nearly circular, and the walls obtusely rounded on the edge. The -ui;e in the 

 cell-mouths not observed " (Billings, loc. cit. p. -_'f)3). 



This species is by no means of common occurrence. The few examples which exhibit 

 the internal contracted aperture at the bottom of the expanded calice. can be detennine'l with 



; but those in which these apertures are concealed, can hardly be .-cparated i'n>m a small 

 undetermined I'm-n.-iii, .< which abounds in the same beds. The /'.' rib s in '|ii' -tion occur.- in 

 the furm of small .sub-cylindrical, irregularly lobed, or sub-palmate ma- 'icrally from an 



inch to an inch and a half in height, the corallites bein^ unequally sized, polygonal, and thin- 

 walled. The difficulty is still further increased by the fact that Striatopora Lu 'l"es 



not appear to p<sess the radiating striae which are so characteristic of the -.cnus. 



Locality and Formation. Rare, in the Hamilton Formation of Bartlett's Mill-, i, 

 Arkona, Township of Bosantjuet. 



Genus TRACHYPORA (Edwards and Ilaime). 



< 'orallum dendroid, the branches presenting calices which are only slightly -alient. ami 

 in which there are DO radiating .-epta ; cn-in-ncliyma ver\ abundant. solid, and with the Mir' 

 marked by Strong irregular, vermicular, and sub-echitiulated -tri;e. " tKd'.vanl- ami Hairn--. 



Pol. 1- ' Terr. Paltoz. p. 305). 



M. M. Kdwanl- and Ilaime have described one species of thi- genus / / ) from 



the J)evonian K'ock- of Kurope, and Mr. Billing- hi- reeordi-d another ; '/'. :i"in tin' 



BamiltOD group of Ontario. 



(','.'. TRACHYPORA ELBG \\ TOLA (l!illin 

 Tr<i'-/ii/jii,i-<i <l,,/<infiil<i (Hillings/, r,//,, /,//' Journal, New Sen,-, \'ol. V. p. -jr.!. 



Corallum solid. raUKMe ; th-- Stems from on.' and a half I.. I\\o liiif- ill diam. !,]-. brancli- 

 in- at an an-le of ?.' . ( 'orallite- arranged in four or five fOWS, parallel with tin- diivetion 

 of tin' axi- of tin- branch. < 'alier- excavated in th'- c. i-neneh\ ma. oval, about two third- "f a 

 line in their Ion- ,,] vertical diaiiidi-r. and half a line in tlirir .-hort or transvcr-.- diam. t. r. 

 Tin- calice- are -urroun-le.l by a pnniiineiM mar-in, and an- u-iiall\ -. -parated b\ inti-rval- of 

 about half a line \,,t uncommonly an extra corallite is intercalate, 1 betueen the regular 

 \.-rtical row-. The .-nrl'ace uf the CM-iiene|i\ ma i- ornamented with .-li'jlitlv flexiioii- br.'k.-n 

 -tri;'. four or live <,| which ..ccii|.\ th. .('one line. 



Thi- de-ant Bpeoiee i- readilv ili.-iin-ui-h. ! from the niiK other known form o| the 

 i/.. '/'. /' by it- e.il- arranged in a lineai and it- nmi .chinulate -! 



/.' llily and I Hamilton l-'ormatimi of I5aril.it - Mill-, near Arkona. T.>\MI- 



-lllp "I I 10 -ail' filet . 



i 11.1:1 MI I : 



'allum rani' r ineiu-tiir/. c, .in| ..,-, d of elmi-/:iie,| b:i-aliif..rm OO 



which are in el..-.- , ..... tad. an. I ar-- not unite, I |,\ :,n\ QQ n- neh\ m.i T.ibu ..t \\ 1, <! fdoj 

 -e|,ta ab-.-nt . n" mural p.| 



