256 EVENINGS AT THE MICROSCOPE. 



We will now see if we can separate the animal from its 

 tube, so as to examine its lower parts. By a gentle pres- 

 sure upon the bottom of the tube with the edge of a pen- 

 knife, which I bring to bear upon it by the aid of this 

 simple microscope, the creature is induced to wriggle out 

 of his case. Eeplacing now the cover of the live-box, 

 and placing it again on the stage of the compound micro- 

 scope, we see that the lower part of the body forms a foot 

 analogous to that of a Brachiomis, covered with ring-like 

 wrinkles, and separated from the body by an abrupt con- 

 striction and diminution of the diameter. At the very ex- 

 tremity there is a sort of sucking-disk, by which we may 

 presume the hold of the animal upon the plant is main- 

 tained. No organic connection subsists between the foot 

 and the tube ; for the latter is not an essential part of the 

 animal, though absurdly called a lorica by Ehrenberg, but 

 only an accumulation of mucus successively exuded from 

 the body, and thrown off in the form which it possesses by 

 the contractions and other movements of the body. 



But see ! the poor naked creature is writhing in con- 

 tortions, which become more and more convulsive and 

 spasmodic : and now it evinces great rigidity in these, till 

 the body has become almost shapeless, portions of the 

 surface being here and there violently forced out into pro- 

 jections, and the foot strongly curled up. The only signs 

 of life that now remain are the occasional fitful workings 

 of the jaws. Are we then to suppose that the shelter of 

 the gelatinous case is needful to its continued existence ? or 

 did I inflict a mortal injury upon it when I laid the edge of 

 my penknife upon its lower part to drive it forth ? Most 

 probably the latter is the true solution. 



Out of the colony that remains, we will now select 

 another specimen, with ripening eggs, in order to watch 

 the development of the young. Here is one with three 

 eggs lying obliquely in the tube, one -of which is already 

 showing the impatient movements of the embryo within. 



