PLATE LXVII. 



Page. 

 Fig. 1. Menophyllum (?) excavatum n. sp 511 



a. View of a typical example of this species. 



Madison limestone, Crowfoot Ridge, Gallatin Range, lower part of bed 27. 



b. Longitudinal section of another specimen, showing, but not completely, the depth 



of the calyce. 

 Madison limestone, Crowfoot Ridge, Gallatin Range, bed 31. 

 e. Transverse section of another specimen taken through the calyce, showing septa 



of two orders slightly developed. 

 Madison limestone, Crowfoot Ridge, Gallatin Range, lower part of bed 27. 



d. Transverse section of the same specimen, taken a little lower down. Indications 



of the fossula and the commencement of the fossular wall can be seen. Septa 

 of the second order are not shown in the drawing, but appear iu the original 

 section as small projecting points. 



e. Another section of the same, still more proximal. The large fossula is well 



developed; the fossular wall and aborted fossular septum are well shown. 

 Septa of the second order are represented by low ridges, two of which, not 

 shown in the figure, are found on either side of the fossular septum. 

 /. Transverse section through another specimen referred to this species. The fossular 

 septum here is extended clear through the fossula to the opposite wall, bisect- 

 ing it, and the whole is much thickened by stereoplasma. 

 Madison limestone, Crowfoot Ridge, Gallatin Range, bed 31. 

 Fig. 2. Clisiophyllum teres n. sp 514 



a. Transverse section showing fossula, columella, and tabula ('?). The latter is not 



adequately represented in point of continuance aud distinctness. Secondary 

 septa, not shown in the figure, can be seen in the original, x 2. 



b. Another section a little more proximal than the above, and showing much the 



same characters, x 2. 



c. Another section still more proximal, from the same specimen. The figure shows a 



somewhat too great development of dissepimental tissue, x 2. 



d. Another section of same, still more proximal, x 2. 



Madison limestone, summit of Three River Peak, Gallatin Range. 

 Fig. 3. Michelinia 2>l<*centa 510 



a. Lower or epithecal surface of a specimen. 



Madison limestone, divide between Gallatin Valley aud Panther Creek, near Big- 

 horn Pass, Gallatin Range, bed 24. 



b. Another specimen, showing size and other characters of the cell apertures. 



Madison limestone, east side of Gallatin River, west of Electric Peak. 

 Fig. 4. Syringopora surcularia n. sp 510 



a. Portion of a section showing size and arrangement of the coralhtes. 



b. An enlargement of the same. 



Madison limestone, Crowfoot Ridge, Gallatin Range, bed 28. 

 Fig. 5. Syringopora aculeata n. sp 509 



a. Portion of a section of. the type specimen, showing size and arrangement of the 



corallites. 



b. An enlargement of the same. 



Madison limestone, Crowfoot Ridge, Gallatin Range, bed 29. 



Fig. 6. Aulopora geometrica n. sp 508 



a. Portion of the coralluni of type specimen, showing size and arrangement of the 

 corallites. 

 Madison limestone, cherty belt, Bighorn Pass, Gallatin Range. 

 584 



