THE HIGHER CRYPTOGAM I A. 287 



in water the outer membrane, which is in the process of 

 being transformed into elaters, is coloured pale blue by- 

 iodized solution of chloride of zinc ; in the middle layer the 

 blue is more intense. 



In sporangia a little more advanced the thin parts of the 

 outer membrane disappear : the delicate pellicle which held 

 together the coils of the elaters is no longer present. Fresh 

 elaters are coloured a greyish-blue by the above-mentioned 

 solution, with the exception of a thin outer layer which 

 assumes a yellowish colour. By adding a quantity of 

 water the colour of the main portion of the elaters becomes 

 a more pure blue. After the separation of the elaters the 

 middle spore membrane exhibits a very different reaction 

 with iodine ; it remains yellow under all circumstances, 

 under the iodized solution of chloride of zinc, as well as 

 under iodine and sulphuric acid. Ainmoniated oxide of 

 copper if applied to the outer membrane just after it has 

 split to form the elaters, is very rapid in its effects. The 

 membrane becomes distended and is gradually dissolved. 

 Under the action of the same fluid the next inner membrane 

 swells up into a large vesicle, without diminishing per- 

 ceptibly in thickness. Its substance is then softer; by 

 rolling it under a covering glass it is easily wrinkled. The 

 third membrane is tightly stretched upon the cell-contents. 

 The further action of ammoniated oxide of copper gives it 

 a yellowish colour, but in other respects it remains un- 

 changed. 



A little later, whilst the elaters are continually increasing 

 in breadth and thickness, the rudiment of a final innermost 

 membrane of the spore becomes visible. If a young spore 

 in this stage of development is detached from its elaters, 

 and placed in alcohol, and if water be then added, the 

 membrane next to the elaters becomes detached from the 

 third membrane, and from the cell-contents which are 

 closely embraced by the latter, and in which chlorophyll 

 now begins to appear. If the spore be now ruptured by 

 pressure, the membrane next to the elaters remains folded 

 without changing its volume. The next inner one remains 

 after the rupture tense as before, whilst it contracts upon 

 a much smaller space, and now appears considerably thicker 



