314: EVENINGS AT THE MICROSCOPE 



(Echinus miliaris); and I might have passed it by with a 

 feeling of satiated curiosity, had I not recollected our 

 evening's amusement. Oh, ho! said I, what a fund of 

 microscopic entertainment is enclosed in this stone box! 

 So I brought it home, and now produce it as the text of 

 our conversazione. 



Every part is a wonder; but we mast examine each in 

 order. Take the spines first. 



As we examine these organs on the animal crawling at 

 ease over the bottom of a saucer of sea-water, using this 

 triple lens, we see that each is a taper pillar, rounded at 

 the summit, and swelling at the base, where it seems to be 

 inserted into a fleshy pedestal, on which it freely moves, 

 bending down in all directions, and describing a circle 

 with its point, of which the base is the centre. Each 

 spine is for the greater portion of its length of a delicate 

 pea- green hue, but the terminal part is of a fine lilac or 

 pale purple. The whole surface appears to be fluted, like 

 an Ionic column, but this is an illusion, as you will see 

 presently, 



I now detach one of the spines, cutting it off with fine- 

 pointed scissors as near the base as I can reach. I put it, 

 with as little delay as possible, into the live-box, and ex- 

 amine it with a high power, say 600 diameters. Look at 

 it. You s^e the ciliary currents very distinctly ; and if you 

 move the stage so as to bring the basal portion into view, 

 you may discern even the cilia themselves, very numerous 

 and short, quivering with a rapid movement. The cur- 

 rents are not longitudinal, but transverse, and somewhat 

 peculiar. The floating atoms which come within their 

 vortex are drawn in at right angles to the axis of the 

 spine, and are presently hurled away in the same plane; 



