348 KOFOID AND SWEZY. 



gallinarum and Trichomastix gallinarum. In one instance (PI. 7, 

 Fig. 80) it is divided into two granules but these are regarded by us 

 as the initial step in the prophase of mitosis. Its diameter is 0.5- 

 0:2 fi. 



The blepharoplast gives rise to the four flagella which pass across 

 the narrow film of cytoplasm and emerge at or near the anterior end. 

 Three of these flagella, the anterior ones, are shorter than the fourth, 

 and are usually directed anteriorly in a single cluster which lashes 

 from side to side, or which may spread out and each flagellum act 

 independently of the others in its position and movements. These 

 flagella are about 1.5 times the length of the axostyle in length. The 

 remaining flagellum is a trailing one but does not differ in diameter 

 or stainability from the others Its length, however, is nearly twice 

 as great, and in locomotion it trails posteriorly in a sweeping curve 

 at one side of the body. Its position and relative length suggest its 

 homology with the marginal filament and posterior flagellum of the 

 undulating membrane of Trichomonas though it exhibits no trace of 

 heavier caliber or greater stainability such as is characteristic of both 

 the marginal filament and cliromatic rod within the undulating 

 membrane of Trichomonas, though not of their extension in the free 

 posterior flagellum. 



The axostyle is a slender hyaline rod, of nearly uniform caliber 

 throughout, sometimes slightly tapering distally, sometimes slightly 

 enlarged in that region. Its length is about twenty times its diameter 

 and ranges from 10-15, rarely 18 /x. Anteriorly it terminates without 

 enlargement in the blepharoplast and posteriorly it contracts rather 

 abruptly to a sharp point. We have found no structure w ithin it. Its 

 shape is subject to considerable variation. It is straight or nearly so 

 in elongated forms (PI. 7, Fig. 80) and often much curved almost to a 

 semicircle or bent at right angles in rounded ones (PI. 7, Fig. 94). 

 In life it is subject to incessant turning from side to side in a fashion 

 difficult to follow in the combined rotation, amoeboid movement; and 

 axost^lar contortions of the organism. It appears to be the localized 

 center in which these powerful movements occur which resemble as 

 much as anything the labored strokes of a heavy stout flagellum. In 

 fact this axostyle more than that of any species we have exann'ned 

 resembles an intracytoplasmic flagellum whose movements are im- 

 peded by the tenacious medium in which it is imbedded. Its posterior 

 end often projects for a short distance as a naked shaft beyond the 

 cytoplasm, even for as much as 0.3 of its length. It forms the axis 

 along which blobs of cytoplasm may be severed by plasmectomy from 

 the body, and dropped off at the posterior end (PI. 7, Fig. 80). 



