1900] MICKOSCOPICAL JOURNAL. 329 



chimney-pots ; others again are compact and fan-like in 

 shape, whilst others present delicate finger-like processes 

 to view. Thay surprise us also because of differences in 

 texture, some being as soft as velvet, whilst others are as 

 hard as wood. 



Such diversity in size and color, form and texture, 

 prompt the question, Are they animals or plants ? 



This same question was asked of Aristotle more than 

 2,000 years ago, and from his answer we may conclude 

 that he was practically convinced that they were animals. 

 It was not, however, till the end of the last century that 

 English naturalists had any definite theory to put forth 

 on the subject. In 1762, Mr. Ellis, a London merchant, 

 classed them as animals from his observations on the cir- 

 culation of water through them, and a very early edition 

 of tlie "Encyclopedia Britannica," 1797, which contains a 

 reference to his work, describes them as a '^genus of ani- 

 mals belonging to the class Vermes and order of Zoo- 

 phytes." It is, however, only in comparatively recent 

 times, and after the most patient labour and exact meth- 

 ods of microscopical study that their true place in nature, 

 as belonging to the great division in the animal kingdom, 

 viz., Metazoa, or many-celled animals, has been definitely 

 established. We shall be able, with the abundant mate- 

 rial at our disposal, and with the aid of a strong magni- 

 fying glass, a glass tumbler, a sharp razor, a deep watch- 

 glass, and a little patient watching, to discover some of 

 the facts upon vvhicli their present classification is based. 



One of the most convenient forms to take for examin- 

 ation will be a specimen of the cylindrical variety belong- 

 ing to the family Syconid®. These forms are found at- 

 tatched to the under surface of loose stones, and are usu- 

 ally about I inch in length, and yellowish-brown in color. 

 They can easily be detached from the stone by the point 

 of a knife, and be transferred to a vessel containing salt- 

 water. Sometimes they attach themselves to pieces of 



