Plate 16 

 Cellarinella njegovanae, new species, and C. roydsi, new species 



(For explanation of abbreviations see key for plate 12. All figures drawn with aid of camera liicida) 



Figure A: CeUarineUa njegovanae, new species. Three zoids of medium calcification 

 Upper lip of orifice forms a faintly bulging horizontal pebbled roof over the deeply buried 

 oral ledge, here heavily shaded. Scale b of plate 12. 



Figure B: C. njegovanae. External avicularial mandible with hooked tip, and oval I 

 lucida area. Scale c of plate 12. 



Figure C: C. tijegovanae. Young zoid. Arched distal lip is characteristic of a youngiJ 

 orifice. Compare with orifices of older zoids shown in figure A. Scale e of plate 12. i 



Figure D: C. njegovanae. Primary orifice of a just-forming zoid, which is so young that ' 

 external avicularia are not yet formed. Zoid is located at distal growing tip of coloii\. 

 Scale e of plate 12. i 



Figure E: C. njegovanae. I'.nd walls of two zoids. A pair of heavily calcified processes 

 arch over sieve plates, which are here heavily shaded but not shown in detail. Scale b of 

 plate 12. 



Figure F: C. njegovanae. Sieve plate as seen from underside, the side away from the 

 pair of calcareous processes. Scale b of plate 12. 



Figure G: C. njegovanae. External avicularial mandible. Back area shown in solid 

 black for comparison of size and shape. Scale c of plate 12. 



Figure H: C. njegovanae. Cross section of part of branch cut at node, showing the 

 bilaminate, flattened character of the colony. Chief difference between sections made at ] 

 level of an internode (pi. 14, fig. G) and at a node (present figure) is in the reduction ol 

 zooecial cavity diameter at node. Only an 18-zoid fragment of the 27-zoid branch cmss 

 section is shown here. Scale a of plate 12. 



Figure I: C. njegovanae. A few incomplete zoids in process of formation and the calci- 

 fication of frontal wall. Lowest zooecium has advanced to stage where suboral avicularial 

 chambers are already outlined. Ovicells are forming on the three biggest zooecia. The 

 frontal wall still incomplete. Two upper zoids are in early stages of frontal wall formation. 

 Frontal wall here consists of two layers. Primary layer, olocyst, is thin, smooth, shiny; 

 secondary layer, tremocyst, is rougher, thick, and porous. Scale b of plate 12. 



Figure J: CeUarineUa roydsi. new species. A flat, broad, branching colony with chiti- 

 nous rootlets at its base. Scale a of plate 15. 



Figure K: C. roydsi. Another, broader, slab that is broken off at basal end and at 

 right branch. Scale a of plate 15. 





i 



