INJURIES INDUCED BY PLANTS 



and partly on the mycelium. Between the surface of the ground 

 and the depth of some two inches they form clusters of small 

 spheroid bodies round the vine or tree. The sporocarps, which 

 are very hard, deep brown in colour, approximately spheroid in 

 shape, and 2 mm. long, are provided with short stalks. They 

 are completely closed, 

 and enable us to refer 

 DematopJwra to the 

 Tuberacei. The elon- 

 gated filiform asci, 

 however, which swell 

 out on one side like a 

 lop-sided turnip to en- 

 close the eight spores, 

 distinguish this para- 

 site from all known 

 Tuberacei. Demato- 

 pJwra necatrix is thus 

 the sole representative 

 of a new genus of 

 Tuberacei. 



The method which I 



FIG. 35. Root of a vine 

 showing numerous scle- 

 rotia-like tubers, on 

 which a few bristle - 

 shaped gonidiophores 

 have developed. 



FIG. 36. A portion 

 of Fig. 35 after 

 the gonidiophores 

 have been formed ; 

 magnified five 

 times. 



at first recommended 

 of starving the para- 

 site by means of iso- 

 lating trenches, &c., 

 having proved too 



tedious a process, it remains to be seen whether the impreg- 

 nation of the poles with creosote can do anything to combat 

 the disease in the vineyards. 



CUCURBITARIA LABURNI * 



This parasite frequently gains an entrance through wounds on 

 Cytisus Laburnum, destroying the cortex and branches for con- 

 siderable distances, and even killing the whole plant, Besides 

 the dark brown spheroid perithecia, which are arranged in groups, 



1 Cucurbitaria Laburni, auf Cytisus Laburnum. Freiherr v. Tubeuf, 

 Cassel, Fischer, 1886. 



