142 



THE AGUE PLANT. 



Dr. Bartlett has recently read before the Chicago Society of 

 Physicians and Surgeons a communication on the Ague Plant, 

 already noticed by us (" Grevillea," vol. i., p. 95), and of which he 

 has given the following more minute description : — 



Safford's plant consists of body and what would appear to be a 

 root. The body, or globe, consists of a wall enclosing a cavity. 

 The layers of this wall are two ; an internal structureless envelope 

 of a dull white color, like the retina in the cadaver, and an outer 

 green wall, apparently resting upon the first as a basement mem- 

 brane, which is much more complicated. It is composed of a 

 great number of green cells ; these are circular, and enclose green 

 contents. The contained material seems to be divided by lines 

 running across the cell, which do not, however, display any definite 

 arrangement. At this point of development the cells furnish the 

 observer no indication as to the granular or cellular condition of 

 their contents. When injured they appear to discharge other very 

 small and greenish cells of a simpler construction. The green 

 wall cells do not adhere very tenaciously to the white membrane. 

 They are readily detached from the latter by gentle friction and 

 maceration, and float off on to the root or other adjacent body. 

 Of the construction of the cavity of the plant within the white 

 membrane I have no knowledge. It seems to be a simple sac. 

 The globe of the plant, at maturity, collapses, the upper circum- 

 ference falling in upon the lower in such manner as to leave to the 

 view a cup, in place of a sphere. At first glance it would seem 

 that the upper hemisphere of the globe had been thrown off, and 

 that the observer was looking into the concavity of the lower 

 hemisphere. More careful examination will show that the globe 

 has collapsed, its contents escaping, and the upper half of its wall 

 falling down upon the lower. The collapsed plant generally pre- 

 sents the cell wall unbroken. Occasionally the upper depressed 

 half is slit open through its centre ; frequently, along the margins 

 of the cup, at the junction of the depressed and stationary portions, 

 there are lacerations of the wall. When the soil containing the 

 plant is removed from its natural bed and placed in different con- 

 ditions, the collapse of the globe seems to be precipitated. The 

 walls, examined immediately after having fallen in, appear of a 

 darker colour, as if moistened. The cavity of the plant contains a 

 colorless fluid, which, it is presumed, is spontaneously evacuated when 

 the globe collapses. It is forcibly ejected if the plant be punctured. 

 I have never had an opportunity to examine it with a higher power 

 than 200 ; I can therefore say nothing of its composition ; it is 

 probably simply nutritive. Under certain conditions, as when an 

 attempt is made to preserve the plant in glycerine, the green wall, 

 losing entirely its cellular character, becomes rumpled up, and 

 massed upon the inner tunic. 



