MOSS ANIMALCULES (BRYOZOA) 



953 



II (12) Cuticula thick and brown, with a keel that broadens at aperture. 



Free statoblasts elongated; proportions i : 1.53 to i : 2.8. 



Plumatella princeps Kraepelin 1887. 



Tubes openly branched, repent, 

 with short lateral branches, antler- 

 like. . . . .Var. a, emarginaia. 



Colony robust, branched often ris- 

 ing from subtratum. Keel little de- 

 veloped. Statoblasts elongated. 



Var. j8, fruticosa. 



Vertical branches predominate, 

 forming an intertwined mass. 



Var. y, mucosa. 



Vertical tubes fused into a mass 

 from which only the aperture rises 

 free. . . . Var. d, spongiosa. 



Fig. 1^98. Plumatella princepSj var. a. (a) Portion 

 of colony, two-thirds natural size. (6) Branch much 

 magnified. (After Kraepelin.) 



12 (ii) Cuticida rarely browned or keeled. Free statoblasts nearly circular, 

 I : I to I : 1.5. . . Plumatella polymorpha Kraepelin 1887. 



Tubes creeping with short vertical side 

 branches. Cuticula semi-transparent; but 

 variable; keel not evident. 



Var. a, repens {= P .-arethusa Hyatt). 



Tubes repent, branching or thickly inter- 

 twined, covering the substratum. Few or no 

 vertical branches. Cuticula lightly colored to 

 transparent Var. /3, oppressa. 



Tubes repent, with many elongated and 

 branched vertical rami. Cuticula semi-opaque, 

 no evident keel Var. 7, caespitosa. 



Tubes repent. Vertical branches close to- 

 gether, even fused, forming great solidness. 

 Cuticula brown, aperture hyaline, slightly 

 elongated Var. a,/MngAsa. 



Fig. 1399. Ptfumatella polymorpka,v&i. a. (a) Young colony, two- 

 thirda natural size, (h) Branch much magnified, {c) Statoblast 

 X 40. (After Kraepelin.) 



