EXPLANATION OF PLATE XXXI. (continued). 



FIG. 



27, 28. VASICOLA CILIATA, Tatem. 27, Animalcule contained within its lorica, x 150 ; 

 28, free-swimming zooid (Tatem). 



29. STROMBIDINOPSIS GYRANS, S. K., x 200. 



30. TINTINNUS sp., C. & L., empty lorica, x 150 (Clap. & Lach.). 



31. TINTINNUS VENTRICOSUS, C. & L., empty lorica, x 200 (Clap. & Lach.). 



32, 33. CODONELLA GALEA, Hkl. 32, Animalcule fully extended beyond the orifice of 

 its lorica, x 200 ; 33, empty lorica, showing its tesselated character 

 (Haeckel), 



34-37. CODONELLA CAMPANELLA, Hkl. 34, Fully extended animalcule enclosing cen- 

 trally numerous ovate germs, x 200 ; 35, empty lorica ; 36, ovate germ, with 

 contained endoplast and contractile vesicle ; 37, earlier spore-like condition 

 (Haeckel). 



38. CODONELLA ORTHOCERAS, Hkl., x 180 (Haeckel). 



39-43. TRICHODINOPSIS PARADOXA, C. & L. 39, Adult animalcule, profile view, 

 x 200 ; 40, ventral acetabulum with plicate horny ring, x 300 ; 41-43, 

 internally developed corneous elements (Clap. & Lach.). 



44. TRICHODINA MITRA, Stein sp., x 300 (Clap. & Lach.). 



45. TRICHODINA STEINII, C. & L. Acetabulum with denticulate ring, x 250 



(Clap. & Lach.). 



46, 47. TRICHODINA SCORP^ENA, Robin, lateral and ventral views, x 400 (Robin). 



48-52. TRICHODINA PEDICULUS, Ehr. 48, Examples adherent in various positions to 

 the portion of a tentacle of a Hydra ; 49, two animalcules in lateral view, 

 x 150; 50, depressed free-swimming zooid; 51, conically contracted 

 animalcule showing at or oral aperture, as delineated by Busch ; 52, apparent 

 example of conjugation between a large and small zooid, a, after Busch. 



53. TRlCHODiNA-like larva, or Trochosphere of Polyzoon, Alcyonidium 

 gelatinosum, as delineated in note-book placed at the author's disposal by 

 H. E. Forrest. 



54, 55. SCYPHIDIA PHYSARUM, C. & L., expanded and contracted zooids, x 200 

 (Quennerstedt). 



