29G EVENINGS AT THE MICROSCOPE. 



for its form is trumpet-sliaped, resembling that of a 

 Stentor with a wreath of cilia around the head, inter- 

 rupted at tM'o opposite points: the central portion of 

 the head rises into a low cone. There is as jet no 

 trace of the beautiful double-petalled flower. 



It has been whirling giddily about the live-box for 

 about a quarter of an hour, but now it begins to 

 manifest tokens of weariness ; or rather the time is 

 approaching for it to select a place of permanent 

 sedentary abode. Its motion is sensibly retarded ; it 

 now and then adheres to the glass momentarily, by 

 its foot, and moves forward by successive jerks, not 

 proceeding more than its own length at a time, and 

 this apparently with effort. The periods of its remain- 

 ing stationary become longer, so that you may suppose 

 it Anally settled two or three times, before its wander- 

 ings are quite over, some shock or alarm sending it off 

 to a little distance again. 



At length it wanders no more; its foot holds fast 

 to the glass, and its movements are confined to whirl- 

 ings round and round on this as a pivot, and to sudden 

 contractions of length. Presently we see a very deli- 

 cate film surrounding the point of attachment; — the 

 first rudiment of the tube, a ring of mucus thrown off 

 from the skin, and pressed down to the foot by the 

 contractions of the body. Meanwhile, the ciliary 

 crown is dividing itself into two, and now we see 

 already the essential form and appearance of the 

 mature animai, every moment developing its perfec- 

 tion. 



