Plaie 13 

 Cellarinella rossi, new species 



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



Figure A: Colon}' sprig showing two internodes and nodes. Scale d of plate 12. 



Figure B: Enlargement of internode showing six zooecia. Some frontal pores are in 

 slight swirling grooves. Zooecia! boundaries indeterminable externally. Scale a of plate 12. 



Figure C: Zoid frontal wall as seen from inside. Central area of upper frontal expanded 

 and imperforate, lower frontal narrower and perforated by many frontal pores. Two small 

 calcareous processes project over a sieve plate in end wall. Region of orifice, oral ledge, and 

 internal avicularium were obscured by broken fragments so are blacked out here. Scale b 

 of plate 12. 



Figure D: The strongly arched peristome is flanked on one side by a very tall, sharply 

 pointed, naked mucro; on the other by a lower, avicularium-bearing mucro. Lower proximal ! 

 edge of orifice is as\'mmetrical. Scale b of plate 12. 



Figure E: Inner surface of zoid, in vicinity of orifice, shows shape and size of internal 1 

 avicularium and its position relative to diagonal frontal oral ledge. Scale c of plate 12. i 



Figures F, G: Two external avicularial mandibles drawn directly from their places in i 

 the colony (i. e., not dissected out). Rims and curved tips are chitin-reinforced. Scale c " 

 of plate 12. I 



Figure H: Peristomial area seen from side. A very well developed, calcareous, visorlike 

 peristome shades the orifice. To one side of it is a prominent mucro. The other mucro is 

 barely indicated diagonally downward from the left. Above the peristome is nonporous ; 

 area under which lies the ovicell. Peristomeal visor extends considerably beyond primary 'i 

 orifice. Scale b of plate 12. 



Figure I : View, slightly from the side, of nonovlcelled zoid tipped downward to show 

 asymmetrical orifice with its diagonal frontal oral ledge that contributes to the almost 

 channeled effect at lower right corner. The "channel" is on same side of longitudinal 

 midline as internal avicularium and on opposite side of midline from the external 

 avicularium. Peristome In this zoid Is not so well developed as that In figure H but still is 

 of considerable size. Scale b of plate 12. 



Figure J: Nonovlcelled zoid tipped backward and a bit sideways to show shape of stout 

 bare mucro and medium-sized peristome. Avicularium-bearing mucro may be on either 

 right or left side of orifice. Here It is shown at opposite side from those in figures D and I. 

 The avicularium does not point downward In this zoid. This avicularium direction is not i 

 common. Scale e of plate 12. 



Figure K: Nonovlcelled zooecium tipped forward so Interior of orifice is visible. The 

 peristome Is worn down or broken off in this well calcified specimen; diagonal frontal oral 

 ledge is quite thick. The internal avicularium, not visible, is behind and below this ledge but 

 is invisible from this view; a mucro Is over this area. External avicularium is heavily calcified 

 and has a strong cross-bar against which the mandible would normally rest. One of the 

 larger avicularia of the colony. Scale c of plate 12. 



