810 



the middle of their length, tapering, with, sometimes, a rather undu- 

 lating outline, to the distal extremity, and a little narrowed towards 

 the base. 



" Scattered in the lower portion of the corolline tube, are hairs of a 

 different structure, consisting of a single series of several cells. These 

 narrow from the base to the apex, and are similar in form and struc- 

 ture to the hairs of the petioles of the leaves, and interpetiolary pro- 

 cesses, which 1 shall shortly notice. 



" The corolline hairs are remarkable, from their fibro-cellular cha- 

 racter. The nature of the spiral fibrous deposit is, however, difficult 

 to determine. A first glance, with a magnifying power of perhaps 

 200 or 300 diameters, discovers the appearance of a narrow fibre, 

 winding, in a spiral direction, up the inner wall of the cell, ascending 

 to the right (as seen from its axis), and closely applied to the appa- 

 rent outer cell-membrane, which has become in part absorbed. 

 Numerous elongated and narrow slits, or line-like markings, occur 

 throughout the spiral ; but whether they are openings between the 

 edges of an individual thread, or series of fibres, or analogous to the 

 dots and slits of broken vascular tissue, it is not very easy to pro- 

 nounce. 



" When examined in fluid, this fibrous deposit has the appearance 

 either of a coil of irregular breadth, or of a plexus or branching 

 arrangement of fibre ; between the threads of which, a line of division 

 is perceptible. If a dried hair be placed under the microscope, we 

 see but slits, narrow and rounded at the extremities, in the direction 

 of the spiral ascent. These are probably an altered condition of the 

 exceedingly fine separating lines which we discover in the fresh state. 

 The portions of fibrous matter intervening between these openings is 

 of very irregular breadth. The threads of the fibre vary, from the 

 l-6000th to 1- 9000th of an inch, in breadth. After observation with 

 my highest magnifying power, one of Powell & Lealand's excellent 

 quarter-inch objectives, I am not prepared certainly to describe the 

 true condition and arrangement of this secondary spiral deposit. 



" In a hair of the young corolla (the latter about the l-6th of an 

 inch in length), I observed the spiral arrangement pretty distinctly. 

 In the younger stages, the cuticle does not appear to have become 

 absorbed to such an extent as in the matured cell, a double wall being 

 perceptible towards the extremity of the hair. 



" The primordial utricle is readily separated from the cell-wall by 

 the application of reagents. A solution of chloride of calcium, a fluid 

 frequently useful in mounting vegetable dissections, produces this effect 



