32 Prof. Bailey on the Crystals found in Plants. 



in great quantity. I have, however, not been able to complete 

 my examination of the different anomalous forms just mentioned, 

 nor of the acicular raphides, (said by Raspail to be composed of 

 phosphate of lime,) which are so common in most monocotyle- 

 dons, and in many dicotyledons. I shall pursue this inquiry as 

 opportunity presents itself, and if any results of interest are obtain- 

 ed, I hope to make them the subject of another part of this memoir.* 



EXPLANATION OF THE FIGURES. 



The figures are all drawn to the same scale, shown in fig. 24. 



Figs. 1 and 2, a b. Different positions of crystals, form B, from 

 Hickory, Carya. 



Fig. 3. Crystals in situ, in bark oi Populus grandidentata. They 

 present the same appearance in the liber of the Locust, Chestnut, Wil- 

 low, and many other trees. 



Fig. 4. Unntiodified oblique rhombic prism ; occurs in Rosaruhiginosa. 



Fig. 5. The same form, with the acute edges replaced by the planes e, e. 



Figs. 6 to 8. Different positions of crystals of form A. 



Fig. 9. Compound crystal resulting from composition parallel to the 

 plane P ; a very common form. 



Fig. 10. Crystal of form B, from Quillaja, showing the plane angles. 



Fig. 11, a b. Crystals of form B, found sparingly in bark of Pine. 



Fig. 12. Portion of the inner layer of the bark of Firms strobus^ 

 showing a fragment of a latex vessel containing crystals. 



Fig. 13, Right rhomboidal crystals, isolated, from bark of Pinus 

 strobus. 



Fig. 14. Conical termination of a vessel from bark of Torreya taxi- 

 folia, covered with very minute crystals. 



Fig. 15. Bunches of crystals (form C) or conglomerate raphides of 

 Quekett. 



Fig. 16. Bunch of two crystals only, from Carya. 



Fig. 17. A single cell from the tubers of Potato, showing small cubi- 

 cal crystals, a a, occurring occasionally among the starch globules, b h. 



Fig. 18. Right square prisms in the cells of the outer coatings of the 

 common Onion. 



Figs. 19, 20, 21. Crystals in bark of Rhus typTiina. 



Figs. 22, 23. Crystals of oxalic acid. 



Fig. 24. Scale showing -jVVl^s of a millimetre, magnified equally 

 with the drawings. 



* All the results mentioned in this paper were obtained by me before I heard of 

 Payen's highly interesting researches upon crystals, with which I am even now only 

 acquainted by means of a brief notice in the Microscopic Journal, Vol. II, p. 213. 



