Hamilton Group, 



183 



angular pits ; there are also conical nodes, one or two at each aper- 

 ture, forming the most prominent feature of the surface. 



Locality — Darien, Y. 



Callopora hemispherica, n. sp. 



Hemispheric masses ; under surface a wrinkled epitheca ; cells tubu- 

 lar, cylindrical, at the center at right angles to the base, becoming 

 more and more oblique as they approach the margin ; cell walls 

 thin, septa wanting; apertures circular, very closely but irregularly 

 disposed , diameter 50 mm. : margins thick, strongly elevated ; inter- 

 mediate space with angular pits varying in size and shape; maculae 

 gently rounded, with larger cell-apertures ; interior intercellular space 

 irregularly vesiculose, or composed of tubili with regular septa. 



Locality — York, N. Y, 



LICHENALIA, Hall 



LiCHEXALIA STELLATA, n. sp. 



Expansions or masses ; cells tubular, cylindrical ; walls thin; septa 

 infrequent , intercellular space vesiculose ; cell-apertures circular, usu- 

 ally oblique to the surface ; diameter .33 mm., quite regularly arranged 

 in undulating intersecting rows, frequently alternating and subimbri- 

 cating, sometimes presenting an arched or triangular appearance; 

 centers of the maculae depressed, smooth, distant 6 mm., bases con- 

 tiguous ; apertures near maculae radiating, and presenting a stellate 

 appearance. 



LiCHENALIA FOLIACEA, ?l. Sp. 



Apertures circular or oval, regularly alternating and imbricating; 

 diameter .40 mm ; the upper portion of the cell walls are sometimes 

 exposed nearly their entire length, carinated, giving to the aperture a 

 triangular appearance ; maculae distant 10 mm., elongate, without 

 apertures , cell-apertures nearest the maculae larger. 



Locality— West Bloomfield, N. Y. 



LiCHEJf ALIA CONSTRICTA, U. Sp. 



Expansions or masses ; apertures circular, oblique to the surface, 

 very closely disposed , on a portion of the surface the intermediate 

 space is occupied by mmnte angular pits, on the highest portion of 



