PLATE LIV. 



.Fenestella (Unitrypa) fastigata. 



Page Ul. 

 VifT. 1. A fraj^ment, natural size, showinij the carina and connecting' processes. 

 Fig. 2. The same fragment, natural sizo, showing: the non-celluliferous side. 



Fig-. 3. A lateral view of a branch enlarg-ed. showing a transveree section of the dissepiments and con- 

 necting pi-ocesses or scalae. (X 6.) 

 Pig. 4. A transvei'se section of the bran(!hes, also showing the depth of the connecting scalse. (X 6.) 

 Fig. f). An enlargement of a portion of the non-cellnlifei-oiLs face of a frond. (X ti.) 

 Fig. 6. An enlargement of the summits of the cai-inaB and the connecting scalse. (X 6.) 

 Upper Helderberg group. ^alU of the Ohio river. 



FeNKSTELLA (UmTRYPA ?) CONSIMILI8. 



I'age 14i. 



Fig. 7. An enlargement of the 8UMimit.s of the carinte and connecting scalse. This form might very 



readily l>e mistaken for the non-celluliferous face of other Fenestelloid forms. (X 6.) 

 Fig. 8. An enlargement of the cellulifei-ous face of a frond ; the carina is broken away, showing the form 



and arrangement of the cell apertui-es. (X *"•) 

 Fig. 9. An enlargement; the two branchet* on the right have the surface broken away, showing the 

 inteiior ; the next two bran<'hes have the carina broken away and show the form and arrange- 

 ment of the cell apertuivs ; the left of the figure shows the siiniraits of two carinje and their 

 connecting gcalie. (X H.) il .'Kiirii'. 



Upi>er H-l.l.ii .' .'■•■•nn. Wnh"'!'\ ii.ilnr,,., Canada. 



i**wil ml 



FkNKSTKLLA (I.-i()IHVI'.\) CO.NMITNOTIVA. 

 I'nge US. 

 ^1^, 10. An erUargemeiit of a portion of the non-ctdluliferoiis side of a fi-oml, showing somewhat flattened 

 branches, with a row of nodes along the miiMle, .ind .i pdriforrn opening on nearly all the 



dissepiments. (X 6.) , . , 



« ' y^ ■• ' ,(!(niK 1.11.. 1' , . , • - 



Fig. 11. An enlargement, showing raanued branches without nodes aiul witl),yery conspicuous openings in 

 the dissepiments. ' 



Fig. 12. An enlargement, showing the angular and carinated branches and dissepiments, with a few open- 

 ings in the latter, and these on the lower portion ; in this respect differing from every other 

 specimen (X 6.) 



Fig. 13. An enlargement, showing a mold, in the rock, of the celluliferous face, and the summits of the 

 carinie. (X 6.) 



Fig. 14. An enlargement of the snmmit of the carina and connecting scalse. (X 6.) 



Fig. \ft. An enlargement of the celluliferous face, the carinae having been broken away, showing the form 

 and arrangement of the cell apertui-es. (X 6.) 



Fig. 16. A lateral view of the uj)|ier half of a branch. (X 6.) 



Fig. 17. A fragment of a fi-ond, natural size, showing the summits of the cariniE and connecting scalse. 



Fig. l!^. A fragment of the non-celluliferous face of a fi-ond, natural size, showing the size of the branches 

 and mode of growth. 



Fig. 19. An enlargement, showing angular, carinated branches, which are straighter than those rejire- 

 sented in fig. 12 ; the porifopra openings are on the upper side of the dissepiments. (X 6.) 



Fig. 20. An enlargement, showing the under sides of the summits of the carinae and their connecting 

 »cal«. (X 6.) 



Fig. 21. An enlargement of the specimen illustrated by fig. 11, to show more plainly the striations on the 

 branches and the character of the openings on the dissepiments. (X 18.) 

 Upper Helderberg group. Walpole, Ontario, Canada. 



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