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, emarginata. 



Colony robust, branched often ris- 

 ing from subtratum. Keel little de- 

 veloped. Statoblasts elongated. 



Var. /3, friUicosa. 



Vertical branches predominate, 

 forming an intertwined mass. 



Var. 7, mucosa. 



Vertical tubes fused into a mass 

 from which only the aperture rises 

 free. ..... Var. 5, spongiosa. 



Fig. 1398. Plumatella princeps, var. a. (a) Portion 

 of colony, two-thirds natural size, {b) Branch much 

 magnified. (After Kraepelin.) 



12 (11) Cuticula 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, repcns { = P .-arcthusa Hyatt). 



Tubes repent, branching or thickly inter- 

 twined, covering the substratum. Few or no 

 vertical branches. Cuticula lightly colored to 

 transparent Var. jS, opprcssa. 



Tubes repent, with many elongated and 

 branched vertical rami. Cuticula semi-opaque, 

 no evident keel Var. 7, cacspitosa. 



Tubes repent. Vertical branches close to- 

 gether, even fused, forming great solidncss. 

 Cuticula brown, aperture hyaline, slightly 

 elongated Var. b, Jiuigosa. 



Fig. i?99. PlumaleUa polymorpha, vnr. a. (a) Young colony, two- 

 thirds natural size, (b) Branch much magni6ed. (c) Statoblast, 

 X 40. (After Kraepelin.) 



