ZOOPHYTES 



rents be produced by the action of the Annelid or by 

 other causes. They are not rhythmical; each individual 

 appears to be animated by a distinct volition. 



Applying a higher magnifying power than we have yet 

 used to the animals, we find that the head-lobe encloses 

 a central cavity; that the arms are also hollow, with thick 

 walls, marked with transverse lines, indicating flattened 

 cells, and muricated on the exterior; and that the body 

 contains an undefined, sub-opaque nucleus, doubtless a 

 stomachal cavity. 



I cat out, with fine scissors, a segment of the tube, in- 

 cluding two of the parasites, with the portion of the net- 

 work of threads that carried them. They have become 

 immediately paralyzed by the division of the threads, but 

 those that remain on the tube are unaffected by the vio- 

 lence. Subjecting one of the animals so cut out to the 

 action of the compressorium, with a power of 560 diame- 

 ters, the arms are seen to be formed of globose cells, made 

 slightly polyhedral by mutual pressure, set in single series. 

 The interior of these organs is divided by partitions, placed 

 at intervals of about the diameter. Some at least of the 

 cells contain a small bright eccentric nucleus. 



When the tissues were quite crushed down by the press- 

 ure of the compressorium, a quivering motion was visible 

 among the disjointed granules, but it was very slight. No 

 trace of cilia, nor any appearance of ciliary motion, was 

 perceptible during life. 



When I first discovered these strange beings, I was as 

 much astonished by what I saw as you are; nor could 1 

 imagine to what class of animals they were to be referred. 

 Neither did I know whether their presence on the tube of 

 the worm was a mere accident, or whether it indicated a 



