78 Forty-fourth Report on the State Museum. 



nodes ; it has also a very close resemblance to S. recta^ but may be 

 distinguished by its less rigid appearance, much more frequent 

 bifurcations, and greater variation in size between the ordinary 

 cell apertures and those of the marginal rows ; from P. tumulosa 

 and S. suhrigida it may be distinguished by its more frequent 

 bifurcations, the oval cell apertures and the narrower ridges ; from 

 Ptilodictya parallela by the narrower frond, more frequent bifur- 

 cations, smaller, more elongate-oval cell apertures, more promi- 

 nent and more closely arranged longitudinal ridges ; from ;S'. incisu- 

 rata by its more frequent bifurcations, smaller and generally more 

 elongate-oval cell apertures, and the nodose, comparatively 

 stronger longitudinal ridges ; from S. sinuosa by the straight con- 

 tinuous ridges ; from S. trilineata and S. tumulosa by the narrower 

 form, more frequent bifurcations and much more prominent longi- 

 tudinal ridges ; from S. rigida and S. cresceiis of the Upper Hel- 

 derberg group it is distinguished by the more frequent bifurca- 

 tions, smaller cell apertures and comparatively stronger ridges ; 

 from ^S'. fruticosa and S. ovatipora by the much smaller cell 

 apertures. 



Formation and locality. — Hamilton group, near Muttonville, 

 Bristol township, Ontario county, N. T. 



Stictopora palmlpQS. 



Stictopora palmipes, Hall. Trans. Albany Institute, vol. x, p. 189, 1881. 



** " " Keport of State Geologist for 1883, p. 41, 1884. 



*' ** " Palaeontology of New York, vol. vi, p. 255, pi. 



Ix, figs. 19, 20, 1887. J 



*# * * -jf * 4e- ^ * 



This species resembles S. hifurcata in having oval cell apertures, 

 arranged in regular longitudinal rows, separated by prominent, 

 nodose ridges ; but it differs from that species in having lateral 

 branches, and in the non-celluliferous margin occupying the entire 

 space between them. S. recta and S. angularis have prominent 

 longitudinal ridges much elevated above the peristomes, but the 

 branches of those species are regularly bifurcating, are narrow, 

 rigid in appearance, and the margins are essentially parallel. 

 From all other species, at present known from the Lower and 

 Upper Helderberg and Hamilton groups, this one may be dis- 



