230 BOTANICAL MICROTECHNIQUE. 



ample, Saponaria officinalis. No certain statements can be 

 made as to its chemical composition (cf. J. Dufour II). 



b. Floridean Starch. 



411. Colorless granules have been observed in the cells of 

 the Floridea, which correspond, as Van Tieghem (I, 804) 

 recognized, in most of their chemical characters, especially 

 in their behavior with caustic potash and hot water, with 

 ordinary starch, and which show, under the polarizing mi- 

 croscope, a similarly oriented cross to that of the latter. 

 With iodine these granules, which are commonly termed 

 Floridean or Rhodophycean starch, usually take, however, 

 only a yellowish-brown to a brownish-red color. According 

 to more recent investigations of Belzung (I, 224), in many 

 Floridece the younger starch-grains, especially, are colored 

 blue by iodine. We have at present no more exact chem- 

 ical studies of the substance of Floridean starch. 



c. Phaeophycean Starch. 



412. Schmitz (I, 154 and II, 60) has observed in the cyto- 

 plasm of the Phceophycea colorless bodies quite insoluble in 

 water, but which are not colored at all by iodine. Berthold 

 has disputed (I, 57) the occurrence of such bodies. 



d. Paramylum. 



413. The paramylum-grains, recognized in the cytoplasm 



of the Euglence and by Zopf (I, 17) in 

 the amoebae and cysts of Leptophrys 

 vorax, have mostly a disk-shaped or 

 rod-shaped form (cf. Fig. 54, I) ; but 

 ring-shaped grains have also been seen 

 (Fig. 54, II and III). 



Klebs (I, 271) observed an evident 

 stratification in the large paramylum- 

 T grains O f Euglcna Ehrenbergii, which 



FIG. 54. Paramylum-errams. I, & . 



oi Eugiena acus- II, of Pha- j s however, very characteristic m its 



cus parvula :\\\, of Euglena * 



spirogyra; iv, a-c, of EU- arran rr e ment and differs markedly from 



giena Ehrenbergn seen from & 



sides (X 400> ' After that ^ the starcll -g rams - These para- 



mylum-grains consist, as is shown in Fig. 54, IV, a-c, which 



