EXPLANATION OF PLATE XXV. 

 Fig. 



1-5. Peridinium tabulatum, Ehr., vol. i. p. 448.— I, Variety with rounded poles or 

 apices and no eye-like pigment-spot, ventral aspect, X 350 (Claparfede and 

 Lachmann) ; 2, variety with pointed apices, dorsal aspect (Ehr.) ; 3, 

 separate reticulated plate from cuirass, x 600; 4, encysted example, with 

 eye-like pigment- spot (C. & L.) ; 5, example with four pigment-spots, its 

 cuirass cast off (C. & L.). 

 6, 7. Peridinium apiculatum, Ehr. sp., vol. i. p. 449, x 400 (Ehr.), 

 3-13. Ceratium divergens, C. & L., vol. i. p. 453. — 8 and 9, Empty cuirass, dorsal and 

 ventral aspects, showing form and disposition of its component plates, 

 X 500 (C. & L.) ; 10, encysted animalcule (C. & L.) ; 11, example with 

 carapace cast off (C. & L.) ; 12 and 13, the same species as figured by Bailey 

 under the title of Peridinium depressum. 



Peridinium ^qualis, S. K., vol. i. p. 45 1. — Dimensions unrecorded (Will.-Suhm). 



Peridinium spiniferum, C. & L., vol. i. p. 449, x 400 (C. & L.). 



Gymnodinium fuscum, Ehr., vol. i. p. 443, X 300 (Ehr.).— 18, Example of con- 

 jugation or longitudinal fission. 



Gymnodinium pulvisculus, Ehr. sp., vol. i. p. 443, x 500 (Ehr.). 



Glenodinium acuminatum, Ehr., vol. i. p. 446, x 250 (Ehr.). 



Ceratium Michaelis, Ehr. sp., vol. i. p. 453, x 300 (Ehr.). 



Ceratium tripos, MUU. sp., var. macroceros, vol. i. p. 454, x 250 (C. & L.). 



Ceratium kumaonense. Carter, vol. i. p. 458, x 190 (Carter). 



Ceratium longicorne, Perty, vol. i. p. 457, x 300 (Carter). 



Glenodinium cinctum, Ehr. sp., vol. i. p. 446, x 400 (Ehr.).— 28, An example 

 of longitudinal fission or conjugation. 



Peridinium sp., encysted examples, vol. i. p. 447, x 250 (C. & L.). 



Ceratium FURCA, Ehr. sp., vol. i. p. 445, x 350-— 32, Central region, showing 

 more minute structure of the cuirass, x 600 (C. & L.). 



Ceratium tripos, MUU. sp., normal short-armed type, x 250 (C. & L.). 



Melodinium uberrimum, Allman sp., vol. i. p. 445, — 34, Normal animalcule, 

 X 300 ; 35, example dividing by transverse fission (Allman). 



Ceratium tripos. Mull, sp., var. arcticum, vol. i. p. 454, x 300. 



Prorocentrum micans, Ehr., vol. i. p. 461. — 37 and 38, Lateral and dorsal 

 aspects ; 39, empty cuirass, X 303 (C. & L.). 



Ceratium fusus, Ehr. sp., vol. i. p. 456, x 300 (C. & L.). 



Peridinium reticulatum, C. & L., vol. i. p. 449, x 300 (C. & L.). 



DiNOPHYSIS VENTRICOSA, C. & L., vol. i. p. 459, X 350 (C. & L.). 



DiNOPHYSis acuminata, C. & L., vol. i. p. 459, x 300 (C. & L.). 



DiNOPHYSIS OVATA, C. & L., vol. i. p. 460, ventral aspect, x 350 (C. & L.). 



Amphidinium operculatum, C. & L., vol. i. p. 461, x 300 (C. & L.). 



Peridinia sp., encystments, vol. i. p. 448, with contents variously divided, that 

 at 49 with the contained protoplasmic mass separated into eight minute 

 naked Peridinia, x 300 (after Claparfede and Lachmann). 

 51, 52. DiMASTiGOAULAX CORNUTUM, Ehr. sp., vol. i. p. 462, front and lateral aspects, 

 X 300, 



53. Gymnodinium roseolum, Schmarda sp., vol. i. p. 444, x 350 (Schmarda). 



54. Gymnodinium inerme, Schmarda sp., vol. i. p. 444, x 600 (Schmarda). 

 55-57. Peridinium tabulatum, Ehr., vol. i. p. 448, brown variety with cleft anterior 



border, x 300. — 55, Ventral, 56, dorsal, 57, lateral aspects, the example at 



56 enclosing a recurved band-hke endoplast. 

 58, 59. Gymnodinium Lachmanni, S. K., vol. i. p. 444.— At 58 an example dividing 



by longitudinal fission, x 300 (C. & L.). 

 60, 61. Gymnodinium marinum, S. K., vol. i. p. 444, x 600.— At 61 an example 



devouring a smaller monad. 

 62. Ceratium bicorne, Schmarda sp., vol. i. p. 453, x 400 (Schmarda). 



