476 Mr. Bauer on the Ergot of Rye. 



the disease in the plant nor ear, however strongly infected, it required consi- 

 derable trouble and patience to unravel every floret of the ears, which can 

 only be taken up at random ; fi'om what I then observed I was soon con- 

 vinced that the ergot is not an extraneous substance, as some have supposed 

 it to be, but that it really is a monstrosity, or transformation of the embryo, 

 and particularly of that part of the embryo which Gcertner calls the Scutel- 

 lum; however, to make my illustration on that point more comprehensible to 

 the general reader, I consider it necessary to explain the progress of vegeta- 

 tion of the grain. A sound germen of rye, before fecundation, consists of a 

 pulpy cellular substance, enveloped in a delicate membrane, which forms the 

 outer coat of the ripe grain ; and in the middle of this cellular substance is a 

 small cavity, lined with a dark green membrane, from which some mucous 

 fluid seems to exude, but no traces of organization are at that time observable. 

 At Tab. XXXII. fig. 1 is a sound young grain, about four days after fecun- 

 dation, consisting chiefly of the same internal parts and substance as those 

 of the germen before fecundation, but its shape is considerably altered, being 

 much longer, and of a more oval form ; the internal cavity with its green mem- 

 brane is considerably enlarged, and the organization of the embryo is visibly 

 advancing. At Tab. XXXII. fig. 2 is a side view of a longitudinal section 

 of this young grain ; at its base appears the first formation of the embryo, 

 which then consists of a soft substance : in this figure and in fig. 3 the scu- 

 tellum is visible, which is the first part of the embryo formed in all gramine- 

 ous plants, and which in the diseased grains ultimately becomes the ergot. 

 Tab. XXXII. fig. 4 is a front, and fig. 5 a back view of diseased grains 

 from the same ear, and of the same age as the sound grain in figs. 1, 2 and 3 : 

 but its exterior shape is now greatly changed ; the external membrane at the 

 apex of the grain is much shrivelled and contracted, and at fig. 7, vvhich is a 

 side view of a longitudinal section of the same grain, the pulpy cellular sub- 

 stance is also much shrivelled, the internal cavity is much contracted, and 

 the young ergot begins to be formed in the same spot as the scutellura of the 

 embryo in the sound grain, and at that period the young ergot retains still 

 some resemblance to the form of the scutellum of the sound grain (see 

 Tab. XXXII. fig. 7 B., and fig. 8, which is more distinctly seen : the sub- 

 stance of this young ergot is at that period also very soft, of a white colour 



