142 The Naturalist of Cumbrae. 



" I now observed that the motions of the mussel 

 were frequent: after a short time"* it threw out with 

 considerable force two small, well-defined streams 

 of milk-like fluid from an aperture at the posterior 

 margin of the anal current, which shot like two silvery 

 wires through the water, then gradually opened and 

 broke up into a beautiful shower of feathery-looking 

 flakes precipitating rapidly to the bottom. The 

 streams continued at intervals for about a quarter of 

 an hour, and towards the end, when more scanty, they 

 became finer and single. I believe the white matter 

 to be ova. I subjected it to the microscope, and 

 found it composed of little transparent globules, filled 

 with granular matter surrounded by a delicate mem- 

 brane, and, when ruptured, the contents flowed out 

 freely. At the close of the milky discharge, the 

 animal became more restless, and the valves opened 

 more widely. The foot now began to protrude and 

 feel about, and fixed for a few seconds on the jar, then 

 darted in with great force. It seemed to be very sensi- 

 tive, often withdrawing from a slight touch on its own 

 fibres. Again the foot protruded more than an inch 

 and fixed to the jar ; the animal now began to move 

 forcibly up and down, as if endeavouring to drag itself 

 from the byssus ; the peduncled attachment was seen 

 at every pull rising above the valves of the shell ; 

 these motions lasted about five minutes, the foot still 

 adhering to the glass, when, to my joy, I saw a very 

 fine fibre stretched up by its side, and a white spot 

 coming distinctly into view under the tip of the foot. 



" I have since placed other mussels in separate jars, 

 and cut all the byssus close by the shell ; in five hours 



