XIV 



SYNOPSIS OF GENERA. 



Examples : Chatetes (Monotri/pella) arbusculus, pi. ix, figs. 1-3, 6-8. 

 ChcUeles {Monolrt/pella) abruptus, pi. ix, figs. 9-11. 



Ptychonema, n. s. g. [Type, ChiBtetcs tabulatus, H.all.J 



Coralluin niius.sive or ramo.se ; composed of thin-walled, strongly corrugated 

 cells which are apparently without diaphragms in the typical species. 



Example : Chatetes {Ptychonetha) tabulatus, pi. ix, figs. 12-15. 



Trematopora, Hall (Pal. N. Y., vol. ii, p. 149. 1852). 



[Type, Trematopora tuberculosa, Hall.] 



2k)arium ramose ; branches solid. Cells arising from the center of the branch 

 and continuing contiguous to each other until near the surface where they sep- 

 arate, becoming cylindrical and more or less surrounded by spiniform tubuli and 

 interstitial cells. Tabula) usually present ; no mural pores. Cell apertures 

 oval or circular. Interapertural surface sometimes showing evidences of the 

 interstitial cells beneath, but never with conspicuous open mesopores. 



Although no true examples of this genus has been noticed among the mate- 

 rials used for the present volume, it is thought best to give a brief .synopsis of 

 the genus for comparison with the sub-genera arranged under it and also other 

 closely allied forms. 



Trematella, Hall (Report of State Geologist for 1886, advance sheets. Expl. 

 pi. 25. 1886). [Type, Trematella annulata. Hall.] 

 Zoarium ramose, solid. Cells tubular, in contact below, diverging near the 

 surface, intersected by septa. Interapertural surface marked by pseudo-pores. 

 Examples: Trematopora {Trematella) annulata, pi. xxv, figs. 22,23; pi. xxvi, 

 figs. 1, 2. 

 Trematopora {Trematella) glomerata, pi. xxv, figS. 4, 5. 



Orthopora, s. o.. Hall (Report of State Geologist for 1886, advance sheets. 

 Expl. pi. 25. 1886). [Type, Trematopora regularis. Hall] 

 Zoarium ramose, solid. Cell apertures arranged in parallel longitudinal 

 rows. Intercellular space solid, or occupied near the surface by minute tubuli 

 destitute of septa. 



Examples : Trematopora {Orthopora) regularis, pi. ix, figs. 1-8 ; pi. xiii, figs. 

 1-3 ; pi. xxiii, fig. 1. 

 Trematopora {Orthopora) subquadraia, pi. Iv, fig. 10; pi. Ivi, figs. 1, 6. 



