672 H. M. WOODCOCK. 



vidiials the undulating membrane is narrow and incon- 

 spicuous (figs. 40 and 5), but with the increase in size of 

 the body it becomes wider and more prominent. The kineto- 

 nucleus may be relatively large, more particularly in the small 

 individuals; in the parasite of fig. 5 it appears to be four- 

 lobed, as if it were composed of four small masses. The free 

 flagellum is fairly long, varying from 6^ to 9^ f.i. A modifica- 

 tion of this type occurs, but it is very uncommon in this 

 series ; certain pai-asites are relatively very wide, and have 

 the afiagellar end very short and abruptly conical, which 

 gives the trypanosoiue a stumpy appearance (fig. 41). The 

 dimensions of this individual are: Total length, 18i//; of 

 the flagellum alone, about 3^ /u ; while the width is as much 

 as 5^ jii. 



Comparing now the small forms present in the earlier 

 case (case A), the parasites are quite numerous in the bone- 

 mai'row, and to this situation they appear restricted. They 

 are of varying size, but I have not found individuals quite so 

 minute as the smallest of those above mentioned. Parasites 

 which are fairly small, nevertheless, are shown in figs. 46 

 and 47. The former is 25 fi in length and 3j n wide, the 

 flagellum alone being as much asOiju; tliese two trypano- 

 somes coiTespond fairly closely with that of fig. 6 from the 

 other series, the chief difference being the longer flagellum. 

 Here, again, it will be seen that there is considerable difference 

 in the size of the kinetonucleus in the parasites compared. 

 But on the same slide as the parasite of fig. 46, actually only 

 two or three fields away, is another individual almost identical 

 except that its kinetonucleus is nearly twice as large. Com- 

 pare also figs. 44 and 45, and again, figs. 52 and 53. 



Rather larger forms are seen in figs. 49-51. Most of the 

 parasites in this earlier case, however, are comparable rather 

 with the wide, stumpy form alluded to above, than with the 

 fusiform individuals. Typical examples are seen in figs. 

 52-54. The parasite in fig. 54 has a total length of 27 /u, 

 the flagellum being 9ju, and its breadth is 5f to 6ju; the 

 corresponding dimensions of the trypanosome in fig. 53 are 



