1 24 Cincinnati Society of Natural History. 



and a few remarks will here be made relative to them. One species, 

 also here noticed, belongs, perhaps, in Group 1 (Massive species) while 

 another, probably referable here, was originally described as a sea- 

 weed. 



Homotrypa obliqua Ulrich, (Jour. Cin. Soc. Nat. Hist., vol. 5, 



1882, p. 243) was described as dendroid with cylindrical or com- 

 pressed branches; surface with numerous conspicuous monticules, or 

 else smooth : cells polygonal : apertures more or less oblique ; tabulae 

 wanting in the axial region, but both straight and vesicular in the 

 peripheral ; connecting foramina are shown in tangential sections. 

 This last feature renders this species anomalous and apparently throws 

 it out of the Monticuliporoids. It occurs near Cincinnati. 



Petigopora gregaria Ulrich, (Jour. Cin. Sec. Nat. Hist., vol. 6, 



1883. p. 155) was described as parasitic, the corallum consisting of 

 patches from one to three lines in diameter and one-fourth of a line 

 thick : a narrow smooth or wrinkled membrane forms the outer mar- 

 gin, which is slightly elevated : surface smooth ; apertures equal : no 

 interstitial cells; spiniform corallites inconspicuous; walls thin and 

 flexuous ; tabulae apparently wanting. It occurs at Cincinnati. 



Monticulipo?'a hospitalis var. neglecta James and James, was briefly 

 desbribed in the paper on Monticuliporoids, (Jcur Cin. Soc. Nat. 

 Hist., vol. 11, 1888, p. 27.) In the absence of the type specimen it 

 is impossible to give any other details than those there given. This 

 description is as follows: " Corallum irregularly conical: surface with 

 many prominent monticules about one line apart : calices equal in size, 

 sub polygonal : corallites take a direct course from base to apex." 



A species described by Mr. E. O. Ulrich under the name of 

 Monotrypa rectimurahs (Geol. Sur. of Illinois, vol. 8, 1890, p. 462) is 

 similar in many respects to M. undulata Nicholson. Mr. Ulrich's 

 species is described as massive, varying from lenticular to subspherical 

 about four inches or more (10 cm.) in diameter: calices polygonal; 

 surface generally smooth but occasionally with faintly elevated clusters 

 of cells about one-half larger than the rest : corallites direct, with very 

 thin straight walls, angular; tabulae few, complete and horizontal; no 

 spiniform corallites. 



He records this species as occurring at Cincinnati and in Illinois. 



