FIGURES 39-42 



Fig. 39. Peridinium truncatum n.sp. A, apical view of specimen from station 35 

 showing epithecal plate pattern and cross ribs in anterior cingular list; B, antapical view of 

 same with sulcal elements labeled; C, dissection of apex; D, dissection of ventral area and 

 adjacent plates; E, ventral view of specimen shown in A; F, left lateral view of separated 

 right sulcal plate showing internal processes and right accessory sulcal list; G, separated 

 girdle plates; cross ribs on outer surface of girdle plates indicated for only small part of one 

 plate; H, right lateral view of specimen shown in A. Magnification: x 340. Symbols: a, 

 anterior internal sulcal process; antl, ant2, first and second antapical plates; apl-ap4, first 

 to fourth apical plates; as, anterior sulcal plate; dl, dorsal segment of apical list; gl-g4, 

 first to fourth girdle plates; lal, left segment of apical list; la, left accessory sulcal list; 

 11, left sulcal list; Is, left sulcal plate; p, posterior internal sulcal process; pas, posterior 

 accessory sulcal plate; pal, posterior accessory sulcal list; pi, posterior sulcal list; pol, 

 po5, first and fifth postcingular plates; pp, apical pore platelet; prl, pr7, first and seventh 

 precingular plates; ps, posterior sulcal plate; ral, right segment of apical list; ras, right 

 accessory sulcal list; rs, right sulcal plate; vp, ventral apical platelet. Type specimen. 



Fig. 40. A, B, Peridinium truncatum n.sp. A, apical view of specimen with intercalary 

 zones from station 91; B, ventral view of same. C, D, Peridinium truncatum forma acutum. n.f. 

 C, ventral view; D, apical view of same. Magnification: x 230. C, D, type specimen, from 

 station 104. 



Fig. 41. Ventral area and adjacent regions in P. truncatum n.sp. Magnification: x 270. 

 (Cf. figs. 39D, E.) 



Fig. 42. Peridinium pallidum Ost. A, ventral view of specimen from station 13; B, 

 apical view of same; C, antapical view of same; D, dorsal view of same; E, right lateral view 

 of same; F, apical view of separated girdle plates; G, detail of distal end of girdle; H, dissec- 

 tion of ventral area and adjacent plates. Magnification: A-F, x 340; G, H, x 770. Symbols: 

 all, anterior segment of left sulcal list; antl, ant2, first and second antapical plates; apl, first 

 apical plate; arl, anterior segment of right sulcal list; app, apical pore platelet; as, anterior 

 sulcal plate; dl, dorsal segment of apical list; gl-g4, first to fourth girdle plates; i, inter- 

 calary zone; lal, left segment of apical list; HI, left lateral list; Is, left sulcal plate; pas, 

 posterior accessory sulcal plate; pi, posterior sulcal list; pll, posterior segment of left sul- 

 cal list; pol, po5, first and fifth postcingular plates; prl, posterior segment of right sulcal 

 list; prl, pr7, first and seventh precingular plates; ps, posterior sulcal plate; ra, right 

 accessory sulcal plate; ral, right segment of apical list; ras, right accessory sulcal list; rll, 

 right lateral list; rs, right sulcal plate; vap, ventral apical platelet; 1' -4', first to fourth 

 apical plates; la, 3a, first and third anterior intercalary plates; 1", 6", first and sixth pre- 

 cingular plates. 



110 



