[Annals N. Y. Acad. Sci., Vol. XIX, No. 1, Part 3, pp. 45-97.] 
STUDIES ON THE MORPHOLOGY AND DEVELOPMENT OF 
CERTAIN RUGOSE CORALS. 1 
By Thomas Clachar Brown, A. M. 
CONTENTS. 
Page. 
I. Introduction and Historical Sketch ....... 46 
Methods of Working .......... 49 
Sectioning of Corals ......... 50 
Grinding and Sketching.50 
Explanation of terms. ......... 51 
II. Ordovicic and Siluric Corals ........ 52 
Streptelasma profundum ........ 52 
Streptelasma corniculum ........ 56 
Streptelasma rusticum ......... 58 
Enterolasma caliculum ........ 58 
[Zaphrentis] racinensis ......... 64 
III. Devonic Corals ........... 64 
Enterolasma strictum 65 
Stereolasma rectum ......... 67 
Heterophrentis prolifica . . . . . . . 71 
Heterophrentis multilamellosa . . . . . . 75 
Heterophrentis wortheni . . . . . . . . 75 
Heterophrentis edwardsi . . . . . . . . 75 
Heliophyllum halli . . . . . . . . . 75 
Microcyclus discus . . . . . . . . . 78 
Hadrophyllum orbignyi . . . . . . . . 78 
IV. Carbonic Corals ........... 80 
Lophophyllum proliferum ........ SO 
Hapsiphyllum calcareforme ........ 84 
Hapsiphyllum spinulosum ........ 85 
Hapsiphyllum varsoviensis ........ 85 
V. Observations on Development ........ 87 
Conclusions ........... 94 
Genealogical Tree .......... 95 
Bibliography ........... 96 
1 Read at the meeting of the Academy, 1 March, 1909. 
45 
