HYDROCORALS OF THE NORTH PACIFIC — FISHER 549 



Plate 38 



Allopora polyorchis: 1, Branclilet from type (pi. 37, fig. 1, arrow) showing abund- 

 dance of male ampullae and their distribution, front view, X 4^^; 2, terminal 

 twigs from same fragment as pi. 37, fig. 2 (note male ampullae), X 5. 



Plate 39 



Stylaster cancellatus: Front view of central portion of type fragment showing 

 orientation of cyclosystems on anastomosing branchlets and the characteristic 

 female ampullae, X 5. 



Plate 40 



Stylaster cancellatus: 1, Paratype, front of fragment of male colony, natural size; 

 2, back of same colony, X 5, this enlargement representing the obverse of the 

 lower left quadrant of fig. 1; the heaviest branch (arrow) is the ascending 

 central branch of fig. 1. 



Plate 41 



1-ld, Allopora campyleca paragea: 1, Type, one of the larger cyclosystems, with 

 two male ampullae, from a small branch, X 30; la, a branchlet showing 

 ordinary cyclosystems, X 20, to agree with magnifications of figs. 2, 2c, and 

 2d; lb, section of a small cyclosystem but not showing maximum curvature 

 of pore, X 30, style 0.5 mm long, (ip = dactylopore8, that on right is independ- 

 ent of a cyclosystem, section of male ampulla; Ic, style and style chamber of a 

 larger cyclosystem, X 30, showing maximum differentiation of style chamber; 

 Id, three dactylopores and gastrostome, X 60, showing the short dactylotomes 

 and maximum development of dactylostyles. 



2-2e, Allopora campyleca tylota: 2, Type, two of the pecuUar large cyclosystems 

 and associated female ampullae, the lowermost with roof removed to show 

 fenestrated wall, X 20, cyclosystem 1.5 mm in diameter; 2a, style and style 

 chamber of a cyclosystem from branchlet of male colony, X 30, showing 

 only moderate development of spicules on wall of style chamber; 2b, view 

 looking into gastropore from just above tip of style, showing the style chamber 

 and the spiniform outgrowths from its wall (c/. fig. 3), X 60, the outer Une 

 being the boundary of gastropore, here shown in cross section; 2c, a cyclo- 

 system at tip of a lateral branchlet of largest fragment (male colony), X 20; 

 2d, one of the small cyclosystems from a peripheral branchlet and two male 

 ampullae in profile, X20; 2c, section of a cyclosystem, gastropore 1.85 mm 

 deep, style 0.59 mm long, X 20; this view shows the deep-cut dactylotomes 

 for comparison with those of S. elassotomus. 



3, Stylaster elassotomus: Type, cross section of gastropore just above end of style 

 showing spiculate outgrowths from wall of style chamber, X 60 (c/. fig. 26) . 



Plate 42 



1-lc, StTjlaster elassotomus: 1, Type, a cyclosystem viewed directly from above 

 showing the short dactylotomes and the flaring gastrostome of the larger 

 systems, X 20; la, a portion of the above enlarged, X 60; 16, longisection of 

 gastropore, X 20, gastrostyle 0.45-0.5 mm long (see pi. 41, fig. 3) (the 

 shallow dactylotomes are shown at top) ; Ic, branchlet with two cyclosystems 

 and associated male ampullae, X 20. 



2-26, Allopora stejnegeri: 2, Type, a large cyclosystem from a main stem, X 20; 

 2a, two female ampullae and two small cyclosystems from branch, X 20; 

 26, section of cyclosystem and two ampullae, X 20, the right ampullae being 

 the normal female and the left the small sort mentioned in text. 



