liG VEGETABLE ORGANOGRAPHY. 



form or position, that it is not necessary to describe 

 thenn As for Nyctago Jala2^2)ce, the bundles of Raphides 

 are presented to view immediately under the cuticle of 

 the leaf, where it is raised by the point of a knife ; they 

 are distinguished by the naked eye or lens, as little 

 white oblong spots pointed at the two ends. When the 

 tissue is placed under the microscope, the bundles of 

 Raphides are seen as layers under the cuticle ; they are 

 smaller than those of Triioma, but they are detached in 

 the same manner, and present the same appearance ; they 

 are also found in the articulations of the stem. Those 

 of the common garden Balsam ( Balsamina hortensis) 

 differ very little from the preceding, and are also found 

 under the cuticle of the leaves and in the articulations of 

 the stem. 



The bodies observed by Sprengel in Piper magnolics- 

 foUum appear, from the figure which he has published, 

 perfectly to resemble those wliich I have described; but 

 he gives so few details of them that I cannot form a 

 decided opinion upon their identity. 



All the observers who have spoken of these bodies, 

 have considered them as kinds of little crystals, which are 

 formed in the juices of the plants, and are fixed in the 

 intercellular passages. Sprengel and Kieser, in conse- 

 quence, give them the names of very fine Needles (aiguilles 

 tres-Jines) or Needle-shaped Crystals (cristaux en forme 

 d'aiguille), but these terms appear to have the double 

 inconvenience of being compound words, and of 

 affirming upon their nature, perhaps, beyond what has 

 been strictly demonstrated. I have decided for this 

 reason to name them Raphides (a Greek word which 

 signifies needles) ; this name has the advantage of con- 

 necting their form and original name, and it does not 

 affirm any thing beyond what is true. 



