742 FUNGI. 



the yellowish-red Rkagonycha melanura Fabr., but not bees. On this 

 account the beetle in question has been supposed to be instrumental 

 in the development of ergot, and it may possibly be so, but only by 

 transporting the saccharine mucus from one plant to another. 



The honey-dew of rye contains neither oil-drops nor starch. After 

 dilution with water, it produces a rapid and abundant separation of 

 cuprous oxide from an alkaline solution of cupric tartrate. Dried over 

 sulphuric acid, it solidifies into a crystalline mass. After a few days 

 the drops of honey-dew dry up and disappear from the ear. The grain 

 at this period becomes completely disintegrated, and devoid of starch. 



The ergotized soft ovaries are covered with, and penetrated by a 

 white, spongy, felted tissue, the mycelium of the young fungus. It is 

 made up of slender, threadlike cells, the hyphce, the outer layer of which 

 consists of radially-diverging cells, the basidia. The whole mycelium 

 forms by its crevices and folds a number of cavities opening externally ; 

 from its outer layer, which is also called the hym,enium or sperraato- 

 phorum, an immense number of agglutinated, elongated granules, the 

 conidia,&Te separated. These cells, the products of the basidia, are not 

 more than four mkm. in length, and give the floral organs the appear- 

 ance of being covered with a whitish dust. The honey-dew likewise 

 contains an abundance of conidia, but it is only on dilution that they 

 are precipitated and become easily perceptible ; the formation of the 

 honey-dew is intimately connected with that of the conidia themselves. 

 Ergot in this primary or mycelium stage was regarded as an independent 

 fungus by L^veille (1827), who named it Sphacelia segetum. According 

 to Kiihn (1863), it may even be directly reproducd by germination of 

 the conidia within the ears of rye. 



The mycelium penetrates and envelops the caryopsis, with the ex- 

 ception of the apex, and thereby prevents its further growth, destroying 

 especially the epicarp and the embryo. At the base of the caryopsis, 

 there is formed by tumefaction and gradual transverse separation of the 

 thread-cells of the mycelium, a more compact kernel-like body (the 

 future ergot) violet-black without, white within, which gradually but 

 largely increases in size, and ultimately separates from the mycelium as 

 the loose tissue of the latter dries and shrinks up after the completion 

 of its functions. By this growth, the remains of the caryopsis, still 

 recognizable by their hairs and by the rudiments of the style, as well as 

 by the surviving portions of the mycelium-tissue, become visible above 

 the palese on the apex of the mature ergot, now projecting prominently 

 from the ear. Veiy rarely the ergot is crowned by a fully developed 

 seed ; in the commercial drug, the apex is usually broken oiF. 



It is evident that in the process of development just described, the 

 very tissue of the caryopsis of the rye does not undergo a transfovTriationf 

 but that it is simply destroyed. Neither in external form, nor in anatomi- 

 cal structure does ergot exhibit any resemblance to a caryopsis or a seed, 

 although its development takes place between the flowering time and 

 that at which the rye begins to ripen. It has been regarded as a com- 

 plete fungus, and as such was named by De Candolle (1810) Sclerotium 

 Clavus and by Fries Sperm,cedia Clavus. 



No further change in the ergot occurs while it remains in the ear; 

 but laid on damp earth, interesting phenomena take place. At certain 

 points, small orbicular patches of the rind fold themselves back, and 



