A Study of Sonic Grcganncs 15 



phenomenon readily explicable on the ground that food sub- 

 stances are imbibed in this region, the coarser granulations 

 precipitating in the deutomerite and the part with the finer ma- 

 terial in solution transfusing through the septum to the protom- 

 erite to be precipitated in this region as a finer granulation. 

 Between forms with anterior and posterior thickenings and those 

 with a thin, more or less uniform ectocyte it is likely that there is 

 a corresponding variation as to the extent and location of absorp- 

 tion. In Stcnophora juHpnsilH I fin^ a nearly uniform ectocyte 

 and a correspondingly uniform granulation. 



In the case of a transparent gregarine clouding up on being- 

 brought over the Abbe condenser light, I was unable to detect 

 any contraction of the body which might have accounted for the 

 opaque condition. It is just possible that light may influence the 

 physical condition of cytoplasm used to darkness and influence it 

 sufficiently to be observed. 



In young specimens the nucleus shows readily as a clear glassy 

 sphere lying in the entocyte and surrounded by a clear fluid. In 

 some nuclei, the so-called nucleoli are readily visible. In full- 

 grown specimens the nucleus may be faintly indicated in the en- 

 tocyte or wholly obscured. Sections of mature gregarines show 

 the nuclear structure which Griiber (1884) gives for gregarines 

 in general : a vesicular build, a membrane enclosing a clear nu- 

 clear fluid with the contained nucleoli. The nucleoli are very 

 numerous and arranged in involved loops. 



Delage and Herouard (1896) give the position of the nucleus 

 as slightly below the middle line of the deutomerite. While this 

 is the common position it may occur anywhere from near the 

 region of the septum to the extreme posterior portion of the deu- 

 tomerite and either centrally or peripherally within the limits of 

 the entocyte, a fact indicative of the loose structure of the ento- 

 plasm. Rolleston ( 1888) also notes the shifting of the nucleus. 

 Liihe ( 1904) has noted that the nucleus may occur abnormally 

 in the protomerite. It can be readily forced out of the body un- 

 der pressure and found intact in the extruded body content. 



This gregarine occurs typically in pairs of 'Tiead to tail" con- 

 jugates, the conjugates ranging from very small to those of fulj- 



T63 



