BOTANICAL MICROTECHNIQUE. 



342. On the other hand, it is in most cases difficult to 

 make the so-called achromatic figure clearly visible. It is, 

 to be sure, capable of staining to a certain degree, especially 

 when haematoxylin is used, or on double staining with 

 fuchsin and methyl blue ( 325), when the chromatic figure 

 is colored red, the achromatic, blue. But, even in these 

 preparations, it is difficult to clearly distinguish the separate 

 threads of which the achromatic spindle is made up ; and in 

 difficult cases, as in many fungi, it is usually impossible to 

 bring out this figure in this way, A preliminary treatment 

 with reagents will better produce this result. 



[Strasburger recommends fuming hydrochloric acid for 

 bringing out the structure of the " kinoplasm," which in- 

 cludes the achromatic figure.] 



How far the methods lately recommended by Flemming 

 and Hermann for animal objects (cf. 322324) will prove 

 of value in these cases must be determined by further re- 

 searches (compare also 348 a-e). 



IV. The Inclusions of tJie Nucleus (Protein Crystalloids). 



343. As recent investigations have shown, protein crystal- 

 loids are pretty widely distributed in the nuclei of the Pteri 

 <lophytes and Angiosperms (cf. Zimmermann II, 54, and 

 III, 112); but they do not belong to their constant con- 

 stituents, and it therefore seems to me better to treat them 

 as inclusions of the nucleus, like the starch -grains and 

 -crystalloids contained in the chromatophores. No other 

 heterogeneous inclusions have yet been recognized in the 

 nucleus. 



344. In the recognition of protein crystalloids their regu- 

 lar crystalline form is in many cases an aid. Thus the crys- 

 talline structure of the crystalloids from the leaves of Melam- 

 pyrum arvense and Candollea adnata, shown in Fig. 34, 2 and 

 4, can hardly be questioned. Besides, one very often finds 

 also needle-like or rod-like crystalloids, as in the ovules of 



