156 On the Red Coloring Matter of the [No. 9, new series. 



groove, the lower lip of which is minutely ciliated. Furnished 

 with a long, large cilium, having a suctorial extremity, which ex- 

 tends backward from the groove on the sulcated side. Body lined 

 with granular protoplasm and chlorophyll, in which is a hyaline 

 vesicle with red eye-spot and a nucleus as in Euglena. Chloro- 

 phyll becoming of a golden yellow, then brownish, and lastly Ver- 

 million red, as the animalcule passes into the protococcus state. 

 Progression waddling the small end forwards, and the large cilium 

 floating behind. Length, 5 to 8-5600ths of an inch. Found in 

 salt-water pools, and in the sea on the shores of the island of 

 Bombay. 



What then accounts for the red colour in the sea ? Water and 

 salt in the salt-pans at Bombay may account for the red color'm the 

 sea- water of other parts, although the animalcules may not be the 

 same, viz., the formation of red oil in their interior. It is interest- 

 ing, however, to find Darwin's description of the animalcule, which 

 he found to color the sea red a degree south of Valparaiso (his 

 " Journal" on board H. M. S. " Beagle," p. 17). accord exactly 

 with that of Peridinium, as may be seen by comparing our descrip- 

 tions ; while it is not less so to find Salt, (Voyage to Abyssinia, p. 

 195), stating that the animalcules which produced the red color 

 in the Red Sea (15° N.) during the day, became luminous and 

 threw out sparks by agitation after dark ; because, most of Ehren- 

 bergs marine Peridinea are phosphorescent. In further confirma- 

 tion of which, Olafsen and Povelsen's statement may be adduced 

 respecting the red color of the sea on the shores of Iceland, viz., 

 that in 1649, in several gulfs " the night before, the sea appeared 

 all on fire and the day following as red as blood." But it is not 

 necessary for me to cite here all the observations in M. Dareste's 

 " Memoire" in favor of the red color of the sea being in many in- 

 stances owing to the presence of Peridinea, or the white color, to 

 the same animalcules. Suffice it to state that there are many. 



With the explanation of the red color then we have that of the 

 white, which is only seen at night, and appears to be produced by 

 phosphorescence generated in the midst of the oil-globules, be- 

 coming less and less powerful, probably as the Perdinium becomes 

 redder and more nearly approaches to the fixed or protococcus form. 



