KOFOID AND SWEZY: UNAKMORED DINOPLAGELLATA 437 



Key to the Species of Pouchetia 



]. Ocellus diffuse, pigment scattered or amoeboid, lens in several pieces (subgenus 



Pouchetia) , 2 



1. Ocellus integrated, pigment mass compact, lens single (subgenus Pouchetiella) 3 



2. Melanosome ring-shaped, lens bipolar fusus Schiitt .... 



2. Melanosome not ring-shaped 4 



4. Plasma reddish or purplish 5 



4. Plasma greenish or yellowish 6 



5. Plasma rosy, antapical region not contracted, torsion 0.25 turn schuetti nom. sp. nov. 



5. Plasma purplish, antapical region contracted, torsion 0.50 turn purpurata sp. nov. 



6. Plasma pale yellowish, ocellus posterior, body wider posteriorly alba sp. nov. 



6. Plasma bluish green, ocellus median, body ellipsoidal poucheti sp. nov. 



3. Pigment mass rosy, not of melanin rosea (Pouchet) emend. 



3. Pigment mass with more or less melanin 7 



7. Large species, over 100//, in length, ocellus median, horizontal 8 



7. Less than lOO^i in length, ocellus posterior, or if median not horizontal 9 



8. No long apical loop of sulcus, faint striae posteriorly, plasma lavender. ...maxima sp. nov. 



8. Apical loop of at least 1 turn 10 



9. Ocellus far anterior compacta Schiitt 



9. Ocellus not premedian 11 



10. Apical loop of 1.5 turns, surface with longitudinal striae, plasma violet 



violescens sp. nov. 



10. Apical loop of 1 turn, surface with rounded platysomes, no striae June Schiitt 



n. Longitudinal striae present, body rotund striata sp. nov. 



11. No longitudinal striae 12 



12. Length more than 2 transdiaraeters, large species polyphemus (Pouchet) emend. 



12. Length less than 2 transdiaraeters 13 



13. Small species, less than 50/n in length 14 



13. Length more than 50/t 15 



14. Plasma rosy panamensis Kofoid 



14. Plasma ochraceous _. parva Lohmaiin 



15. Apical loop of 1.5 turns, ocellus far posterior atra sp. nov. 



15. Apical loop, if present, with less than 1.5 turns, ocellus not at postmargin 16 



16. Girdle displaced at least 0.75 total length of body purpurescens sp. nov. 



16. Girdle displaced less than 0.75 total length 17 



17. Length more than 1.5 transdiaraeters, lens elongated, granular black pigraent strands 



subnigra sj). nov. 



17. Length not more than 1.5 transdiaraeter, pigment not in amoeboid strands 18 



18. Diffuse rosy pigment throughout body 1<) 



18. Black pigment scattered in peripheral spherules maculata sp. nov. 



19. Ocellus median, displacement more than 0.5 length of body voracis sp. nov. 



19. Ocellus posterior, displacement less than 0.5 length of body rubescens sji. nov. 



