THE SPOROZOA 



217 



result, from the ordinary pattern, and marks the full stop to re- 

 production by schizogony. 



Each microgamete has a flexible, serpentine body, 6-7 //. in length by 

 barely 1 p, breadth in Coccidium, schubergi (Fig. 53, a, b, d, e). It may be 

 extended at full length, or bent up into the form of a U by its own activity. 

 The substance of the body consists principally of chromatin, which, however, 

 contains the above-mentioned vacuole in its interior, and is itself enclosed in 

 a delicate covering of protoplasm, 

 from which spring the two 

 flagella, one at each end of the 

 body. At the extremity, which 

 is anterior in movement, the 

 protoplasmic envelope is more 

 condensed to form a shining 

 point or rostrum (r). From the 

 base of the rostrum springs the 

 anterior flagellum (a.fl\ the chief 

 agent in forward movement ; it is 

 very fine and slender, about twice 

 the length of the body, planted 

 on the side which is convex when 

 the body is curved, and directed 

 backwards. The posterior flagel- 

 lum (p.fl) is a simple continuation 

 of the hinder end of the body ; 

 it is shorter than the anterior 

 one, and acts more as a rudder 

 (" Schleppgeissel "). The micro- 

 gamete as a whole thus bears a 

 striking resemblance to the an- 

 therozoid of a moss-plant. 



In Coccidium lacazeiand Adelea 

 ovata the formation of the micro- 



U 



FIG. 53. 



Microgametes of Coccidium schubergi, Schaud. 

 (a, b, d, e), and C. lacazei (Labbe), (c, /). a, 6, and c 

 are drawn from the living objects ; d, e, and /, 

 from specimens preserved and stained. After 

 gametes differs in One important Schaudinn [51], x about 2000. a.fl, anterior flagel- 



point from the ' process described ^^ 

 above. When the nucleus of 'ong enough.) 

 the microgametocyte breaks up, 



the karyosome divides up first, and its fragments travel to the periphery 

 and act as centres round which the chromatin is concentrated to form 

 the nuclei of the inicrogametes. Hence each microgamete possesses a 

 karyosome. The microgametes of C. lacazei (Fig. 53, c and /) are 

 smaller (3-4 //, in length) than those of 0. schubergi, though otherwise 

 similar, but those of A. ovata have no flagella, and move by undulations 

 of the whole body. 



The macrogametocytes are distinguished both from ordinary 

 schizonts and from microgametocytes chiefly by two points (Fig. 51, 



may be much less marked than is the case in Coccidium schubergi; compare especially 

 the case of Caryotropha mesnilii (p. 223 and p. 225). 



