PLATE XXX. 



» Ctathophyllum Houghtoni. 



Cyathophyllum Houghtoni Rominger. Geology of Michigau : PaljEontology : iued. 



Fig. 1. Lateral view of the upper part of a large specimen, showing the cup and the foliated edges 

 of the numerous inverted cones, of which the whole is composed. 



Fig. 2. Longitudinal section of the same, showing the depth of the cup and the strongly developed 

 rays. The interior cavities have all been filled with a calcareors deposit, obscuring 

 much of the structure ; but a few of the transverse plates can be traced near the base 

 of the cup, and their edges are seen distinctly for some depth near the margin of the 

 specitcen. Hamilton group, Livingston county, N. Y. 



This species presents external characters common to Chonophyllum, and may be 

 regarded as exhibiting a transition to that genus. 



Cystiphyllum conifollis n. sp. 



Fig. 3. Lateral view of an irregular erect growing specimen of the usual size, preserving the epi- 

 theca over nearly the entire surface. Town of Bosanquet, Ontario. 



Fig. 4. View of a sn.ali specimen, from Moscow, N. Y. <• 



Fig. 5. Lateral view of a specimen, preserving the epitheca. The cup is contracted at the summit 

 to less than half the size of the body below. Moscow, N. Y. 



Fig. 6. View of a specimen denuded of the epitheca, and showing the vesicular structure over 

 most of the surface. The calyx is contracted above. Moscow, N. Y. 



Fig. 7. Longitudinal section of a similar specimen, showing the cup-like arr.ingement of the cysts. 

 Moscow, N. Y. 



Figs. 8, 9. Two views, giving opposite sides of a long, slender specimen. One side shows the 

 irregular or intermittent growth, with epitheca; the other side weathered and show- 

 ing the cup-shaped arrangement of the vesicles. The calyx at the top is very small 

 and represents the contracted stage of growth. Town of Bosanquet, Ontario. 



Cystiphyllum Americanum ? 



Fig. 10. A lateral view of a large individual, which is referred with doubt to this species; the cup- 

 shaped arrangement of the vesicles presenting the features of the preceding form. 

 Hamilton group, Moscow, N. Y. 



