STEXTOR. 65 



disc there runs all around a narrow faint band, (fig. 30, r 1 ,) which 

 lies so close to the surface that it is difficult to determine pre- 

 cisely that it is not actually superficial. From this band there 

 arise, at nearly equal distances all round, about a dozen exces- 

 sively faint thin stripes, (r, r,) which converge in a general direc- 

 tion toward the mouth (m). They are, like the circular band, 

 just beneath the surface of the disc. With a microscope of 

 ordinary quality, these stripes would be confounded with the 

 longitudinal, closely set bands which run along the whole length 

 of the trumpet. The circular band has been described by some 

 authors as a circular vessel, which is connected with the con- 

 tractile vesicle ; yet, after the most careful examination, I have 

 concluded that this view is not the true one, but rather as I have 

 here described. 



As I have said, the circular and converging bands of the ner- 

 vous system are evidently in close relation with the most active 

 organs. These organs are the mouth (m) and the vibratile cilia. 

 The former I have described, and will therefore merely state that 

 the convergent stripes appear to enter it and pass into the throat. 



The vibratile cilia (c) are variously elongated, fine, short, 

 hair-like bodies which cover the whole surface of the body. The 

 largest, most prominent, and conspicuous of them are those 

 which fringe the edge of the disc, and are arranged in a closely 

 set series (c) along the outer margin of the circular nervous 

 band (r 1 ), so that they appear to rise directly from it. There are 

 also large rigid cilia (b) scattered over the body. 



At certain periods there may be seen toward the right side of 

 the stem a slender, ribbon-like, yellowish body (w, n l ), which 

 extends lengthwise from near the disc almost to the basal end. 

 Within this body, young (ri) have been seen to originate, and 

 therefore it is looked upon as the organ of reproduction. 



With these facts in hand, we are now prepared to follow the 

 process of budding, and the accompanying internal changes, 

 with a clear understanding of their import. The first change 

 that takes place, preparatory to this phenomenon, is a division of 

 the contractile vesicle into two distinct organs. This separation 



