EXPLANATION OF PLATES 



The drawings of details were made by the writer. The photo- 

 graphs were made in the photographic laboratory of the United States 

 National Museum, ^\^th exception of plates 43, 65, 66, and 68 by 

 G. E. MacGinitie and plates 58 and 60 by Beauford B. Fisher. 



Plate 34 



Allopora carnpyleca: 1, Portion of branchlet of male colony showing two cyclo- 

 systems and associated ampullae, X 20; la, type, longisection of a cyclo- 

 system from side of rather email branch that necessitates the sharp curvature 

 of gastropore, X 20, gastrostyle 0.68 mm; 16, a cyclosystem from main stem 

 of type, with three male ampuUae (two opened), X 20; Ic, type, three dactylo- 

 tomes, X 60, showing relatively siBall pores and small dactylostyle spicules; 

 Id, branchlet of female colony, showing C5'closystems and associated female 

 ampullae, the lowermost sectioned, X 20, longest diameter of cj'closystem 1.2 

 mm; le, type, style and rudimentary style chamber characteristic of male 

 colonies, X 30, gastrostyle 0.68 mm; 1/, style characteristic of female colonies, 

 X 30, style 0.5 mm; Ig, longisection of a cyclosystem of female colony, X 20. 



Plate 35 



1-ld, Allopora polyorchis: 1, Type, a cyclosystem from the posterior face of a 

 larger stem, X 20, cyclosystem 0.93 by 1.1 mm, three male ampullae; la, 

 X 60, section of a style chamber viewed from above as well as from side, so 

 that the style is considerably foreshortened, spicules shown projecting 

 downward from gastropore wall; 16, X 20, cyclosystem and two female 

 ampullae of specimen mentioned in text; Ic, type, X 20, lateral face of a 

 branchlet showing three irregular confluent cyclosystems and an independent 

 system wath the more robust gastrostyles often found in irregular systems, 

 male ampullae above on front of colony, those below on the back; Id, type, 

 X 20, section of a rather deep cyclosystem with also on left a section of a 

 dactylopore. 



2-2c, Stylaster cancellatus: 2, Type, X 20, lateral face of a small t^Nag showing five 

 cyclosystems and female ampullae on front and back of twig, an ampulla 

 opened on left, and end of branch at right; 2a, male specimen, X 20, a shallow 

 cyclosystem viewed in section, with two dactylopores in section; 26, male 

 specimen, X 20, the terminal deeper gastropore of a small twig; 2c, male 

 specimen, X 10, lateral view of a fairly straight branchlet of the twig-net 

 showing three cyclosystems and male ampullae, the gastropore set obliquely 

 as in 2a (note that this figure is half magnification of others). 



Plate 36 



Allopora campyleca: 1, Type, portion of male colony, front view; 2, fragment of 

 female colony, back view showing ampullae. Natural size. 



Plate 37 



Allopora polyorchis: 1, Front view of type colony, male, 390 mm wide and 278 

 mm high; 2, tip of a terminal branchlet enlarged to show characteristic 

 distortion of cyclosystems (this is possibly from a different colony). 

 548 



