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by a septum near the middle into two compartments, and furnished with a 

 long^ish, slender, colourless stem. These are called resting spores, because they 

 survive the death of the host plant. Now occurs a very curious episode in the 

 process of reproduction. If the puccinia spores are caused to germinate they 

 produce from one or both divisions of the spore fine slender germ-tubes, called 

 promyceliiun, and after attaining a definite length of about three or four times the 

 length of the spore, they give off three simple branches which taper from base to 

 apex where eacli bears a single oval or kidney-shaped hyaline spore, called the 

 promycelium spore. If one of these be placed on a young leaf of the common 

 barberry under proper conditions of moisture, it throws out a slender germ-tube 

 which jnerces through the epidermis of the barberry leaf, and in the course of 

 about eight days gives rise to a well-known fungus yEcidiuin berbcridis, or barberry 

 cluster-cups. These cups, vi'hich are filled with golden yellow spores, and grow in 

 clusters, are a favourite object with dilettante microscopists, who delight in a 

 pretty object. The spores are smooth golden-yellow, and nearly globose, and are 

 produced from the mycelium in chains, the oldest and ripest spore being at the 

 top of the chain. These spores will not reproduce the cluster cups directly, but if 

 they alight upon wheat they will at once produce a mycelial tube that enters by 

 the stomata into the tissue of the wheat and produce "rust," or Uredo linearis. 

 This proves beyond doubt that the very ancient belief amongst agriculturists that 

 a barberry tree near a field of wheat produced the rust, rested on a strictly 

 scientific basis, but arrived at by simple observation. I have thus in a very 

 hurried and imperfect manner sketched out some amongst many of the methods 

 by which Fungi are reproduced, and I trust that with the aid of the diagrams 

 I have exhibited the subject has been made clear to you. 



