138 
MURIEL ROBERTSON. 
It seems to occur in the Trypanosome from Hyla 
arborea (Franya, ‘Bull. Soc. Portug. Sc. Nat./ 1907), also 
in T. granulosum (Franya), also in T. loricatum (Dutton, 
Todd, and Toby, ‘Ann. of Trop. Med. and Parasit.,’ No. 3, 
1907). 
The similarity between the life-history of T. vittatse and 
T. raim hardly needs emphasising. T. raiae, of course, 
shows clearly the adaptation to the peculiar habits of the 
Pontobdella, its relatively slow development and the long 
persistence of the resting phase being correlated with the 
stiffening of the blood in the crop and the very long period 
which the Trypanosome must pass in the leech owing to the 
extreme slowness of the digestion. 
The work here recorded was carried out partly at the 
Millport Marine Station, partly in the Zoological Laboratories 
at Glasgow University and the Lister Institute, Chelsea. 
Lister Institute ; 
April. 11*09. 
EXPLANATION OF PLATE 9, 
Illustrating Miss Muriel Robertson’s paper on “ Further Notes 
on a Trypanosome found in the Alimentary Tract of 
Pontobdella muricata.” 
Fi^s. 1 — 24 are drawn with 2 mm. apochr. immersion lens by Ziess, 
I'fO N.A. long tube and oc. No. 12, with the assistance of the camera 
liuada. The magnification is .approximately 4500 diameters. 
Fig. 25 is drawn with the No. 2 eyepiece ; the magnification is 
approximately IfiOO diameters. 
Figs. 1, 2, 3, 4, S, 9, 10, 13, 15, 17, 18, 19, 21 and 23 are from Heiden- 
bain’s bamiatox. preiiarations. The remaining figures are from Delafield 
preparations. 
All fbe figures, with the exception of 25, are from the leech Ponto- 
bdella. 
