CHAP. I. 



RAPHIDES. 35 



but are exclusively placed in the intercellular passages. The 

 slender kind (fig. 14.) he states to be crystals of phosphate of 

 lime, from tV to 3^0 of a millimetre in length, and to be in 

 reality six-sided prisms, terminated at each end by a pyramid 

 with the same base. The crystals found in the Cactus and 

 Rhubarb (fig. 12. and 13.), he says, are composed of oxalate 

 of lime ; and he represents them to be right-angled prisms, 

 terminating in a four-sided pyramid. {Nouv. St/st. de ch. org. 

 p. 522.) Mohl differs fi-om this statement. He says that ra- 

 phides are never six-sided prisms, as Raspail asserts ; but that 

 they are right-angled four-sided prisms, which gradually vanish 

 into points. And he declares that Meyen is right in asserting 

 that the raphides are constantly formed inside the bladders, 

 and never in the interstitial passages of cellular tissue. ( Anat. 

 Palm. p. 28.) 



D 2 



