90 ANNALS OF SCOTTISH NATURAL HISTORY 



D. pyriformis, Perty. Orkneys, Shetlands. 



D. globulosa, Duj. Orkneys. 



Lecquereusia spiralis (Ehrenb.), Blochmann. Shetlands. 

 Nebela collaris (Ehrenb.), Leidy. Orkneys, Shetlands. 

 N. flabellulum, Leidy. Orkneys, Shetlands. 

 N. carinata (Archer), Leidy. Orkneys (Hoy). 

 Heleopera petricola, Leidy. Orkneys. 

 Quadrula symmetrica (Wallich), Schulze. Shetlands. 

 Hyalosphenia elegans, Leidy. Orkneys. 

 Euglypha alveolata, Duj. Shetlands. 



E. ciliata (Ehrenb.), Leidy. Shetlands. 

 Placocysta spinosa (Carter), Leidy. Orkneys. 

 Sphenoderia lent a, Schlumberger. Orkneys (Hoy). 

 Assulina seminulum, Ehrenb. Orkneys (Hoy), Shetlands. 

 Trinema enchelys (Ehrenb.), Leidy. Orkneys, Shetlands. 

 Cyphoderia ampulla (Ehrenb.), Leidy. Orkneys, Shetlands, 



Of the foregoing list some were found in the plankton of 

 various lochs, and these I have tabulated separately. Of 

 the species found in the plankton few can be regarded as 

 true plankton-forms. Only Cyphoderia ampulla and Euglypha 

 ciliata occurred in such quantity as to be unquestionably 

 true constituents of the plankton. 



RHIZOPODS IN THE PLANKTON OF LOCHS IN THE ORKNEYS AND 



SHETLANDS. 



