1883.] Prof. Hillhouse, On the Swelling of Starch Grains. 399 



Desertion of Figures. 



Fig. I. Represents the germination of Phoenix Dactylifera. C is the 

 Cotyledons growing out from the seed s and enclosing the first leaves. R 

 the root. 



Fig. ii. The normal structure of the root. A the epidermis, E the 

 endodermis, Xy the Xylem, Py Phloem, B strands of sclerenchyma in 

 the ground tissue, a section through the plane n. n. in Fig. vi. 



Fig. in. A section through the plane m. in. in Fig. vi. The 

 Phloem has united and increased in size. A branch is being given off at 

 D to the Cotyledon. The Xylem masses are irregular and beginning to 

 branch. 



Fig. iv. A section through the plane iv. iv. in Fig. vi. The Xylem 

 is giving off branches to the Cotyledon. The Xylem branches turn off 

 nearly at right angles, as in Fig. vi. At their ends are seen the Phloem 

 bundles. 



Fig. v. A section through the plane v. v. of Fig. vi., showing the 

 irregularly scattered bundles in the centre and the bundles in the 

 Cotyledon F. 



Fig. vi. A diagramatic longitudinal section. CC section of the 

 Cotyledon. LL section of the first leaf. The bundle is drawn in the 

 plane of the paper, but in the Monocotyledonous plant the bundles do 

 not remain in one plane, but take a kind of spiral course. 



Fig. vii. The germination of Zea Mais. S the seed, Sc the edges 

 of the ruptured scutellum, C the Cotyledon, R the root, A A the node 

 from which the Cotyledon is given off, BB that from which the fibro- 

 vascular bundles are given to the scutellum. 



Fig. vni. Transverse section taken between the nodes AA and BB, 

 Ph the Phloem bundles, S spiral vessels, Xy Xylem vessels. 



(3) Some Observations on the Swelling of Starch Grains. By 

 William Hillhouse, B.A., Professor of Botany in the Mason 

 Science College, Birmingham. With Plate XII. 



Certain peculiar appearances which had come under my notice 

 as the result of the continued action of Chlorzinc Iodine (Schultze's 

 solution) on starch grains in the winter tissues of plants, prompted 

 me to undertake a few separate experiments with the reagent 1 , 



1 The following is the method, based on that of Eadlkofer, in which I prepare 

 this reagent : — Pure granulated Zinc is dissolved in Hydrochloric Acid at an ordi- 

 nary temperature ; the solution is evaporated, at a temperature of about 70° or 

 80° C, and under contact with metallic zinc, to a syrup which does not get muddy 

 on addition of much water, and has the sp. gr. 2-0. This syrup is poured off and 

 diluted with water to sp. gr. 1-8, that is, 12 parts of water are added to every 

 hundred parts of the zinc chloride solution. In 100 parts of the resulting fluid 

 dissolve at a gentle heat six parts of Potassium iodide, and then dissolve in the 



