THE MYXOSPORIDIA OF THE BEAUFORT REGION. 



207 



been seen moving rapidly forward when the posterior process extended out freely behind 

 and was attached to neither the slide nor cover glass. This was conclusively shown when 

 the trophozoite turned quickly to one side; the posterior process swept around and 

 continued to extend straight out behind, which could not have been the case if it was 

 attached. In a few cases in turn- 

 ing the process hit an object and 

 was then bent to one side. In one 

 instance a sporulating trophozoite 

 Off Leptotheca scissura, which was 

 entangled on the slide in a bit of 

 debris was observed. In its efforts 

 to escape the body became greatly 

 elongated by the pulling of the 

 pseudopodia at the anterior end 

 until it finally became small enough 

 to be pulled free. It is true that 

 the posterior process can some- 

 times be seen to elongate as the 

 trophozoite moves forward, but 

 that only occurs when it adheres 

 to some foreign object and is con- 

 sequently pulled out into a long, 

 slender process by the pseudopodia 

 at the anterior end. 



Under dark-ground illumina- 

 tion the long, filiform pseudopodia 

 can be seen to be thrust forward 

 and then sweep posteriorly toward 

 the sides of the body, as in figures 

 3-7, plate XVI, and figure 43, plate 

 XIX. Movements of these pseudo- 

 podia in all directions can be plainly 

 seen; in fact, they move about 

 much like flagella. It is also cer- 

 tain that the filiform pseudopodia 

 can be rapidly absorbed and re- 

 formed. Text figure i shows 

 clearly the formation of these 

 pseudopodia in a trophozoite which had been on the slide for some time, and conse- 

 quently the movements were so slow that they could be easily followed. 



In most cases, possibly in all, in addition to the filiform pseudopodia, short, conical, 

 and branched pseudopodia are formed at the anterior end. These are difficult to see, 

 as they are very transparent and continuously changing. They are simply an exagger- 

 ated form of the wavelike movements of the ectoplasm noted above, which are so char- 

 acteristic of pyriform trophozoites. In the intense light of the dark-ground illuminator 

 the filiform pseudopodia are often retracted after a short time, locomotion then being 



Fig. I. — Movements of pseudopodia in a vegetative trophozoite of either 

 Leptotheca or Ceratomyza sp. from the gall bladder of Cestracion tiburo. 



A, trophozoite with two long pseudopodia, a and b, at anterior end. 



B. 10 minutes later, a has moved to posterior end of body, b has elon- 

 gated and is also moving toward posterior end. C, i minute later, b 

 has nearly reached posterior end and 2 new pseudopodia, c and c, have 

 appeared at anterior end. D, 3 minutes later, c and c have fused, a and 

 b have nearly fused. E. 10 minutes later, a and 6 are completely fused 

 and c has increased in length. X 1000. 



