22 



MICOGRAPHIC STUDY OF SAFFRON DISEASE. 



pierced their integuments, that the parasite appropriates their 

 nutritious juices after the manner of Cuscutas, and induces, if 

 not direct death, at least a weakly development. 



The second disease has received from cultivators of saffron the 

 vulgar name of Tacon,* an old Frencli word borrowed probably 

 from the Italian Taccone, which signifies in either language a 

 piece of leather patched on a shoe-sole. Our first knowledge of 

 this pathological affection is due, as far as I know, to Fougeroux 

 de Bondaroy, who has described it as follows in the Memoirs of 

 the Academy of Sciences at Paris for the year 1782 : — 



<£ Brown spots are first observed in the tissue of the bulb which 

 injure its substance, and though the coat seems sound, the spots 

 beneath enlarge in proportion as the malady increases, the texture 

 is destroyed, the ulcer (for so this disease may be termed) gains 

 ground, consumes the flesh until it is changed into a black dust ; 

 the coats themselves finally change colour, becoming red ; the 

 bulb rots, or rather is reduced to a substance resembling vege- 

 table mould. 



" The malady increases rapidly ; the Tacon is communicated 

 to neighbouring bulbs, but for this end they must either be in 

 contact, or the dust settling on them must communicate the 



disease, and this communication is effected slowly This 



dust is different from that which results from decay. It has 

 rather appeared to me to be of the nature of bunt in wheat." 



The author then compares bunt with the Tacon in respect of 

 propagation : — 



" In wheat it is the starchbearing part which is corrupted ; in 

 the bulb also it is the starch which is first destroyed, and the 

 bulb equally with the wheat turns into a black foetid powder." 



From all which it may be inferred that the disease which 

 attacks the bulbs of saffron, for the communication of which I 

 am indebted to M. Rayer, is not due to the presence of a 

 Mhizoctonia, but is clearly the result of that sort of decay which 

 is called Tacon. The present state of science requiring our 

 investigations not to stop at the surface of things, but that they 

 should be pursued as far as our powers of observation permit us 

 to penetrate, it will not be thought superfluous if I add the 

 following details to the description of Fougeroux. They will 

 enable us to appreciate correctly the mode of change of the 

 tissues examined under the compound microscope, and will com- 

 plete the very imperfect information at present in existence on 

 the nature of this affection. 



* The word Tacon is still used in Spain to signify the heelpiece of a 

 shoe. Our provincial word " tacked," for bletted or decayed in spots, has 

 possibly a Norman origin. Richardson derives it from " tache," a spot, of 

 which the Italian " taccia " is the equivalent. — Tr. 



