282 NOTES FROM THE SOCIETY'S NOTE-BOOKS. 



Unopened Eyelids of a Kitten (PL XIX., Fig. 4). — In this 

 figure a represents the Meibomian glands ; b^ inner surface of 

 eyeUd ; c, bulbs of eyelashes. The two dark patches at the 

 juncture of the eyelids are groups of pigment cells. The Mei- 

 bomian glands secrete an unctuous matter which prevents the 

 eyelids sticking together, and which often collects in sensible 

 quantity on the edges of the eyelids during sleep, especially when 

 glandular action is excited by slight inflammatory irritation. In 

 the human eyelids there are about forty of these glands in the 

 upper lid and a smaller number in the lower. A. H. Searle. 



Section Piper (PL XX., Fig. i). — Double-stained sections are 

 very beautiful, and might be very instructive if information were 

 supplied with them as to the structures they exhibit. Why do 

 some tissues take one colour and others the other ? I suppose it 

 is owing to some difference in the chemical constitution of the 

 cells, etc. This specimen differs from one that came under my 

 notice a short time ago, chiefly in having a welLdefined band of 

 thick-walled cells coloured blue between the outer and inner rows 

 of fibro-vascular bundles. What is this ? A. Hammond. 



Piper. — The question raised by Mr. Hammond is of great 

 interest. It is clear that the Piper belongs to the exogenous class 

 of plants. The specimen so beautifully drawn by Mr. H. at first 

 sight appears to have passed into the second year's growth. 

 There are fibro-vascular bundles beyond the blue ring of cells 

 which encloses the seven fibro-vascular bundles surrounding the 

 pith or medulla. One would be apt to consider that the cells 

 which absorb blue dye consist of woody tissue, and, therefore, 

 that the blue continuous ring marks the first year's growth of the 

 plant. I have spent some hours in trying to solve the problem, 

 but with no satisfactory conclusion. In all works on structural 

 botany the medullary rays are stated to pass from the pith to the 

 bark. In trees these rays, as lines, are plainly seen ; in humbler 

 plants they can be discovered, but with some dififlculty. In the 

 specimen before us the medullary rays cannot be traced through 

 the blue fine of cells, which form quite a dense zone, perfecdy 

 continuous, around the central mass of parenchyma. The cells 

 immediately outside this blue ring are of square form, and the 

 several series of fibro-vascular tissue lie in a circle imbedded in 

 them. It appears, also, that in time another ring of tissue would 

 be formed, the cells of which would also take the blue dye and 

 constitute a second unbroken zone. The absence of the medul- 

 lary rays puzzles me, although it is probable that they are there, 

 but that they have absorbed the blue dye also. I should like to 

 have the matter cleared up by some member clever in structural 

 botany and who is acquainted with the action of double-staining. 



R. H. Moore. 



