Prof. Bailey on the Crystals found in Plants. 27 



mistaken by some observers for right square prisms, although all 

 the modifications prove that they belong to the monoclinate sys- 

 tem. Again, the identity of the corresponding plane angles, in- 

 dicates that they may all be referred to the same set of axes. 

 They in fact, may all be referred to modifications of a right rhom- 

 boidal or oblique rhombic prism. But as these forms belong to 

 the same system as those of table A, and are therefore not in- 

 compatible with those forms, it is even possible that they may be 

 modifications of the same primary. I suspect that this is really 

 the case, for the following reasons. 



1. The form fig. 10, is sometimes found in plants whose crys- 

 tals generally belong to form A, fig. 5. 



2. The plane angles 70° and J 45°, as indicated on fig. 10, are 

 exactly those which would be given by the face P, of form A, 

 fig. 7, if the obtuse lateral edges were replaced by the planes e, e. 



The idea that forms A and B are derived from the same pri- 

 mary, is supported by the similarity in chemical composition, 

 which appears to be proved by the following experiments. 



1. Raspail states,* that the crystals of form B in Orris root, Iris 

 Jlorentina, proved to be oxalate of lime. 



2. Dr. Torrey informed me that the crystals (fig. 10) found in 

 the South American bark, [Quillaja saponaria,) were analyzed 

 by him, and proved to be oxalate of lime. 



3. The crystals in hickory, which agree perfectly in form with 

 some of those occurring in Iris and duillaja, were submitted by 

 me to all the experiments which I performed on those of locust 

 bark, and the results were identical, proving beyond a doubt, that 

 they were composed of oxalate of lime. 



The kind of crystals to which my attention was next turned, 

 was that of the stellate bunches, (conglomerate raphides, of 

 Quekett.) These I shall refer to as form C; (see fig. 15.) 

 These bunches, being mere aggregates of crystals, may be ex- 

 pected to occur in all plants which contain any crystals, and they 

 are actually found mingled with the crystals of forms A and B, 

 in many plants. Still there are certain families of plants, as the 

 Polygonae, Malvacece, Geraniaceas, &c., in which the bunches 

 either occur alone or greatly predominate. 



A list of all the plants in which these bunches were noticed 

 by me, is given in table C. 



* Nouveau Syst. Chim. Organique, Vol. Ill, p, 603. 



