202 The Philippine Journal of Science ms 



Subphylum MASTIGOPHORA — Continued. 

 Class Zoomastigophora — Continued. 

 Subclass Lissoflagellata — Continued. 

 Order Euglenida — Continued. 



is the point of discharge of the oontractile vacuole. Some forms 

 possess chromatophores, and colony forms occur. 

 Family Euglenidse. — These are elongated, more or less pointed, and 

 usually possessed of but one flagellum. Spiral stripings along 

 the body show the course of the myonemes. Green chroma- 

 tophores and red pigment eyespots or stigmata are usually 

 present, as are pyrenoids and granules of paramylum. Typ- 

 ical genus, Euglena Ehrenberg, 1830. 

 Family Astasiidae. — Body is colorless, elongate, and usually pro- 

 vided with a striped membrane. Eyespots (stigmata) absent. 

 Otherwise they resemble members of the family Euglenidae. 

 Typical genus. Astasia Ehrenberg, 1838. 

 Family Peranemidae. — Bodies usually symmetrical and either stiff 

 or plastic. Typical genus, Peranema Dujardin, 1841. 

 Order Silicoflagellida. — Forms found parasitic on Radiolaria. They 

 are of simple structure, having a peculiar latticelike silica skel- 

 eton and one flagellum. Typical genus, Distephanits Stohr, 1881. 

 Subclass Choanoflagellata. — These forms are distinguished by a proto- 

 plasmic collar, which surrounds the base of the flagellum, which 

 may be extended from, or withdrawn into, the body. They are 

 simple in structure. Colonies, which are frequently formed, are 

 embedded in a chitinous or gelatinous matrix. 

 Class Phytomastigophora. — Mastigophora, having marked plant character- 

 istics. The class includes many complex colony forms in which there 

 is division of labor and sexual dimorphism. The individual cells 

 composing these colonies are always of simple structure, possessing 

 eyespots, pyrenoids, and chromatophores, which may be brown, yel- 

 low, or green. 

 Subclass Phytoflagellata. — The chromatophores are yellow or green. 

 Order Chrysoflagellida. — The chromatophores are yellow. Typical 



genus, Synura Ehrenberg, 1833. 

 Order Chloroflagelllda. — The chromatophores are green. Typical 

 genus, Pleodorina Shaw, 1894. 

 Subclass Dlnoflagellata. — The organisms have an outer shell of cellulose 

 in the form of plates and include many fresh-water and marine 

 species, many of great beauty and some of bizarre form. Two 

 furrows usually cut the body. Of these furrows the transverse 

 is the most important. A flagellum lies in this furrow, while 

 another is directed forward in advance of the organism. These 

 flagella impart a rotation and forward movement at the same time. 

 The organisms contain yellow or brown pigment. 

 Order Adinida. — There are no furrows, the flagella lying free in the 

 water. The transverse flagellum has a movement the same as 

 though the furrow were present. Typical genus, Prorocentrum 

 Ehrenberg, 1833. 

 Order Diniferida. — Both longitudinal and transverse furrows are 

 present. 



