1S.S7] 



FARMERS' REGISTER 



241 



Contrary, then, to what ta'.ces place with regard 

 to the ei«'i;s o(' iiijsect?, which are too heavy to be 

 carried ab')iu \r wiiuls, aiui ii' ihey were lighier, 

 are <reiierally, when ,laid, ijlued to the substances 

 destined for the food-*)t' the youni; when hatched, 

 the ininnfe, li-rht, subtle seeds of funi^uses and 

 mosses are floated about in the air wilh the gen- 

 tlest breeze, and in this way dili'used over" im- 

 mense tracts of country, in numbers altogether 

 countless. Tlie discovery of M. Dutrochet is, 

 theretbre, of the greatest interest in making us ac- 

 quainted with ilie economy of Providence in the 

 pronagation ol7ijn<>;i, hitherto ailoirether mysterious. 

 What we term smut, canker, "and rust, are ac- 

 cordniij to this discovery of M. Dutrocliet, on!}' 

 the (i'uit of particular funguses, the plants of which 

 they are the Iruit being hitherto undescfibed and 

 unknown, but which must be sought for in the 

 i'ora\ of delicate fibres, probiibly transparent, and 

 consequently difficult to see in the textures of the 

 corn atiactcil wilh these des^trOctive {)ara6iites. 



It lornis no objection to this view, that the fibres 

 of these limguses have not been seen except par- 

 tially by Bauer.- and .A.d. Brongniart in their ini- 

 crost;opical researches, for M. Dutrocliet tUrlher 

 foatiii, th it when the fruit of the plant oh.served 

 by him (^'-Igaricus crispus), sent up its fooi-stalks 

 (^stipis), it became partially detached li'oni the 

 main plant, and, independent of it /or its future 

 nourishment, the fibres of the main plant indeed 

 becoming e.xhausted of s.ubstance, and disappear- 

 ing as ma)' be seen in what were previously sup- 

 posed to be the roots at the base of the fruit-stalk 

 in the edible mushrwom, which supposed roots are 

 the fibres of the main plant, partly exhausted of 

 their substance from nourishing the fruit. 



Experiments of M. Fee on Parasite Fungi. — 

 Before M. Datrochet's discovery, an excellent 

 cryptogamic botanist, M. Fee, tried some interest- 

 ing experim-Mits on the propagation of the parti- 

 cular sorts of tiingi which are under consideration. 

 JM. Fee collected a number of leaves oi'the Bui-net 

 rose (i?ysa fc/i^yiyZ/a) infected wiih the common 

 rose rust {^Uredo Roses), §o as to be almost cover- 

 ed with it. He then took three rose-trees of the 

 same species quite free from n-st, and having 

 planted them in separate boxes of mould, re- 

 moved them from the vicinity of the rusty plant, 

 taking care, however, to keep them' in a similar 



JM. Fee infers frona these interesting expert- 

 n^.ents, that the seeds or s)jorules of the fungi are 

 sucked up with the moisture of" the soil by the tips 

 or sj)ongioles of the root-fibres, and that the rust- 

 seeds which in the first rose-tree in the box were 

 mixed with the earth, came in contact with the 

 spongioles before the opening cit tfie buds, when 

 the force of attraction being greater, tliey were 

 more readily absorbed and developed tlian after 

 the leaves and flowers have been formed, when 

 the circulation of the sap is less active. At the 

 period when fungi mature their fruit, the wind 

 Ciirries their seeds or sporules in clouds from place 

 to place, Vv'hile the rain precipitates tliem to the 

 ground, and washes them into the soil. The 

 viscid nature of these seeds or sporules when 

 u-etfed v.'ilh the rain, causes them to adhere to 

 the root-fibres of plants, whence they are sucked 

 up with the moisture of the soil, and carried witli 

 the circulating sap into every part' of tlie plant. — 

 .Jnnales Botaniqacs. 



Furnished with these, sure .scientific facts to 

 build upon, we may now consider eacli of the 

 ihree destructive species in their order^ 



1. ^'-hcertained cause of Smut. — The parasitic 

 fungus which causes or is denominated snmt, is^ 

 one of the genus justly termed brand (^Lredo), 

 but differs most distinctly, as we have already- 

 seen, from the canker-brand, by being without 

 smell, and also in its mode of growth; for, while 

 the canker-brand continues during its whole 

 growth in the interior of the grain, the smut brand 

 (Uredo segetum) at maturity bursts through the 

 envelopes of the corn, where it had previously 

 lain concealed while it advanced in growth. 



We have already seea that M. Adolphe Brong- 

 niart maintains, that the affection is chiefly, if not 

 altogether, confined to the foot-stalk or peduncle 

 of the ffrain; but he likewise deemed it necessaiy 

 to investigate whether the powder of the smut 

 should be considered as a modification of the tis- 

 sues composing the peduncle when in a healthy 

 state, or if it were formed in a manner diffi^reut 

 li'om its natural org'anization. . 



The sjjike-stalk (nrcAis), .which supports the 

 grains ahd the floral organs, in corn and grass 

 plants, is fo;-med of an extended cellular tissue, 

 the cells being placed close to each other without 

 any obvious spaces between them, and also of a 



aspect. He then mixed one part of the rusty congeries of vascular fibres, composed of cells 



rose-leaves, towards the end of winter, wilh the 

 mould in the box of one of the rose-trees, reserv- 

 ing the remainder of the rusty leaves for anotiier 

 part of the experiment. 



When the second rose-tree was in full vigor and. 

 near blossoming, some of the affected leaves were 

 frequently shaken over the soil, in order to scatter 



very ranch elongated, of spiral vessels (trachecB), 

 and tlie intervals between them {jps&udo-lrachece). 

 R]. Ad. Brongniart found nothing resembling this 

 structure in the fleshy mass occupied by the smut 

 at any f)eiiod, though he traced the aftisction to 

 the earliest period when it could be distinguished. 

 Even at the earliest stage, then, the fleshy mass 



the seeds or sporules, the remaining portion ofjin the foot-stalk, destined to form the smut, was 

 which continued attached to the leaves. The found to be entirely composed of a uniform fissue, 



rusty rose-leaves were alierwards steeped in wa 

 ter, and the third rose-tree was watered vith the 

 nii-Kture during the spring. 



Till the succeeding autumn, the time probably 

 at which this flingus (Credo Hosm) laturally 

 fruits, the three plants in the boxes exhibited 

 nothing particular. At this season the tree in 

 the box where the rusty leaves had been mixed 

 up with the earth became profusely coveied wilh 

 rust, while the o;her two trees remaineJ quite 

 free. These two were, however, ecjually iffected 

 with the first in the autumn of the second /ear. 



Vol. Y— 31 



presenting cavities nearly four-sided, and compar- 

 atively of oonsiderabie size, separated by partitions 

 Ibrmed of one or two layers of very small cells. — 

 These cavities, which resemble in structure the 

 cells in ,reeds and rushes, were in the smutty ears 

 filled by a compact homogeneous mass composed 

 of veiy fine and minute grains, perftjctly round, 

 and all of equal size. They were of a greenish 

 color in the ear when scarcely unfolded, and 

 slio'htly adhered to each other, though they were 

 only connected by shnple contact, being agfflom- 

 erated towards the centre of each mass. In the 



