40 A COMPOUND SPECIES 



described ; and also that the main stem, above the 

 lowest branch, was coiled up in the s&me way, but 

 not so closely, and that the part below the lowest 

 branch had, curiously enough, remained straight. 

 Sometimes, in large and numerously branched speci- 

 mens, one or two of the lowest members do not 

 contract at the same time with the rest, but do so 

 immediately afterwards, as if they had been startled 

 by the shrinking movements of their neighbours. 

 Sometimes these lowest branches will contract alone, 

 while all the others remain fully extended, a fact 

 that would almost seem to indicate that they possessed 

 an independent life of their own. 



In the accompanying engraving I have attempted 

 faithfully to portray one of these wonderful creatures. 

 Fig. 1 represents it fully extended, while Fig. 2 indi- 

 cates its collapsed form. There is another curious 

 circumstance which I have fortunately observed in 

 connection with this Vorticella, a description of which 

 will perhaps be interesting to the reader. I allude 

 to the casting off of what may be called the fruit of 

 the tree. When this event takes place, the buds (or 

 fruit) dart about with such rapidity, that it is almost 

 impossible to keep them in the field of view for the 

 briefest space of time. A represents the enchanted 

 fruit hanging on the tree ; B shows it as it swims 

 about. 



Although not exactly fruit, it is, no doubt, the 

 means by which the Vorticellae are propagated, for it 



