KOFOID AND SWEZY: UNARMORED DINOPLAGELLATA 



431 



to the left anteroventrallv or aiiterosinistrally. They are thus l)y structure 

 aud position more highly specialized for their function than the looser aggre- 

 gates of the more primitive species of Pouchetia, and than the less integrated 

 ocelli of Pouclietiella, such as P. maculata and P. voracis (figs. PP, 12, 2). In 

 these less integrated types the ocellus is usually farther posterior, smaller, both 

 relatively and aljsohitely, and may have an elongated lens more or less lobed 

 or trausverseh' laminated as in P. voracis (fig. PP, 2), P. atra, and P. maculata 

 (pLll, figs. 126 and 119). 



Fig. PP. Pouchetia Scbiitt and Proterytliropsis gen. uov. 1. Fouchetia funus Schiitt. After Schiitt (1895, 

 pi. 26, fig. 94,). 2. P. voracis sp. nov. 3. P. purpurata sp. nov. 4. P. poucJieii sp. nov. 5. P. atra sp. nov. 6. 

 P. parva Lohmann. After Lohmanu (1908, pi. 17, fig. 2,3). 7. P. j)anamcnsis Kofoid. After Kofoid (1907, 

 ]il. 1, fig. 7). 8. P. alba sp. nov. 9. Proterytliropsis crassicaudata sp. nov. 10, 11. Pouchetia schuetti (Schiitt), 

 After Schutt (1895, pi. 26, figs. 92,, ,„). 12. P. maculata sp. nov. X 500. 



The nucleus of Pouchetia always has distinct beaded, chromatin threads and 

 has not lieen found with the perinuclear mcmln-ane surrounding a hy;iline area 

 al)Out the regular nuclear contents. It is usually located anterior to the ocellus. 

 Tlie exception to this relation, seen in P. com pacta (fig. PP, 9), as oriented by 

 Schiitt (1895), may be due to an incorrect interpretation as to the anterior 

 and posterior ends of the organism. 



