NATURAL SCIENCES OF PHILADELPHIA. 119 



few specimens, however, may always be found which exhibit with sufficient 

 distinctness the outlines of the tissue vesicules. 



Trematopora tubulosa could, for this reason, with propriety, be placed under 

 the genus Diamesopora ; but Diamesopora itself, again, so much resembles 

 Trematopora ossiolata, that I would rather see the genus Diamesopora given 

 up, by amalgamating its only representative with Trematopora. 



The species named by Hall, Ccramopora foliacea, is, in all respects, corres- 

 pondent with the other Trematoporas. It grows in double leaves, which may 

 be separated in two folia, with a dermatic crust on the interior face of the. 

 two leases. Its tubules are, as in the former species, prostrate, and make an 

 abrupt bend to the surface ; the inter-tubular cell-mass exhibits its structure 

 with the greatest distinctness. 



Diameter of tubules one-sixth of a millimeter. From Ceramopora imbricata, 

 the type of the genus, it differs essentially. More natural would have been 

 its combination with Rhinopora verrucosa, which has the structure of Fistuli- 

 pora, and the exterior form in common with it. 



In Rhinopora verrucosa, the maculae are represented by elevated, branching 

 and anastomosing ridges, which are lined with tube orifices of somewhat 

 larger size. 



FlSTULIPORA NEGLKCTA nOV. Spec. 



Convex, undulating, laminar expansions of a few millimeters thickness, 

 with a wrinkled epitheca below. Tubules one-fourth to one-third of a milli- 

 meter wide, with quite projecting, oblique, oval orifices, forming a sharp lip 

 on the outer side, and gradually lost in the general surface on the inner side. 

 They are arranged in closely-set subregular rows, which are interrupted by 

 small, little conspicuous maculae. 



Locality. Waldron, Ind , and Rochester, N. Y., in the shales of the Niagara 

 group. 



Fistulipora Halli nov. spec. 



Undulated, free or incrusting expansions, with a wrinkled epitheca below. 



Tubules one-sixth of a millimeter wide, orifices oval, with au abruptly- 

 projecting lip on the outer side, and arranged in subregular rows, which 

 keep a distance of about one tube diameter. Macula; quite conspicuous, 

 sometimes slightly elevated, of irregular substellate form. 



This species has much resemblance to Ccramopora foliacca, but it does not 

 grow in double leaves as the latter. 



Locality. Waldron, Ind., Rochester and Lockpcrt, in the shales of the 

 Niagara group. 



In the upper strata of the Helderberg group, and in the Hamilton group, 

 Fistulipora is represented by numerous species. The smaller ramose forms, 

 which are so frequently met with in the Niagara group, are rarely seen in 

 this horizon ; larger laminar expansions, or massive tuberoso-globose forms, 

 prevail here. 



Fistulipora lunata nov. spec. 



It grows in tortuous thick laminap, with a wrinkled epithecal crust below, 

 or more frequently in distorted, very irregular masses, consisting of several 

 laminae, which are grown together with their epithecal sides. The tubules 

 are not angular to the surface, with prostrate basal ends as usual. Size of 

 tubules one-fourth of a millimeter. Orifices with moderately-elevated mar- 

 gins, rotundato-semilunar, with two dent-like projections into the tube 

 cavity at the concave or flattened side, which continue as longitudinal ridges 

 down the cavity of the tubes. Distribution of orifices without any apparent 

 order; distance a little over their own diameter. Tube diaphragms some- 

 times developed, frequently wanting. 



Intertubular tissue coarse-celled; cells arranged in subregular vertical 

 rows. 



1866.] 



