232 
Trypanosoma lewisi 
periphery of the nucleus two chromatic rodlets may be seen, having the 
appearance of a membrane (Fig. 3 d, Se, 4a). Often only two chromatic 
granules (Fig. Se, 36, 46), or three of different size (Fig. 3a) are present. 
When comparing Fig. 2a, 26, 2c7 with Fig. Se, 4a, 46, the similarity of 
the results obtained with dry fixation-Giemsa’s stain and with sublimate 
fixation-Heidenhain’s stain, will be evident. 
Giemsa’s stain following fixation in Schaudinn’s liquid does not give 
satisfactory results. Good preparations for demonstration may be 
obtained, but for the study of the nuclear structure they are useless. 
No better results follow staining by Giemsa’s recently described method 
(1909). The nucleus looks like a dark red spot, in which no structure 
whatever is to be seen. 
Tig. 5. a, c, Hermann’s fixation; b, d, Flemming’s fixation, 
followed by Heidenliain’s stain. 
Fixation with Flemming’s and Hermann’s solutions produces more or 
less considerable shrinkage. The volume of the nucleus is reduced and 
the latter is surrounded by a bright halo, thus simulating a nucleus with 
a large karyosome as may be found among Amoebae. Hermann’s 
solution gives better results than Flemming’s. An advantage of these 
fixatives is the beautiful Heidenhain stain, which may afterwards be 
obtained. The nucleus is stained very deeply and so a very sharp 
differentiation is possible. The nuclear structure is the same as that 
obtained by the two methods described, as may be seen when comparing 
Fig. 5a, 5c (Hermann’s fixation) and Fig. 56, 5 d (Flemming’s fixation); 
Giemsa’s stain gives no better results than after corrosive-alcohol. Its 
only advantage is that it gives sharp outlines to the nucleus. 
Very sharp differentiation may be obtained with Heidenhain’s stain 
after fixation in Rath’s solution ; no shrinkage of the nucleus was 
