eae Sy Sea ee 
THE APPRESSORIA OF THE ANTHRACNOSES. 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY. 
LXXXIV. 
HEINRICH HASSELBRING. 
(WITH SEVEN FIGURES) 
In describing a number of new plant diseases in 1883 FRANK' 
gave an account of peculiar spore-like organs produced by the germ 
tubes of spores of the bean anthracnose. He showed further that 
these organs acted as holdfasts, by means of which the fungus 
was firmly attached to its host during the early phase of develop- 
ment. In the same paper he described analogous organs of Fusi- 
cladium Tremulae and Polystigma rubrum, Almost simultaneously 
Fiscu? described the holdfasts of Polystigma, but he did not at all 
recognize their true significance. He regarded them as ‘‘secondary 
spores”? which served in the distribution of the fungus, since the 
ascospores are embedded in slime when ejected, and are therefore 
not suited for dissemination by the wind. FRanx first recognized 
he true nature of these bodies, and gave to all organs of this 
class the name appressoria or adhesion organs. Later MEYER* 
again described and figured the adhesion organs of Polystigma, 
but added no new observations. In 1886 Dre Bary‘ first showed 
that the complex adhesion organs of Sclerotinia were produced as 
the result of a mechanical stimulus, but BtscENS made the most 
complete study from a physiological standpoint. He showed that 
the germ tubes of many parasitic fungi produce adhesion organs of 
* FRANK, B., Ueber einige neue und weniger bekannte Pflanzenkrankheiten. 
Ber. Deutsch, Bot. Gesells. 1:29-34, 58-63. 1883; Landw. Jahrb. 12:511-530- 
pls. 3. 1883. 
ue Fiscu, C.. Beitrage zur Entwickelungsgeschichte einiger Ascomyceten. Bot. 
Zeit. 40:851-870. pls. 2. 1882. 
_ °Mever, B., Untersuchungen iiber die Entwickelung einiger parasitischer 
Pilze bei Saprophytischer Ernahrung. Landw. Jarhb. 17:915-945. pls. 4. 1 
_ *De Bary, A., Ueber einige Sclerotinien und Sclerotinien-krankheiten. Bot. 
Zeit. 44:377 et seq. 1886. 
* BUscEn, M., Ueber einige Eigenschaften der Keimlinge parasitischer Pilze. 
Bot. Zeit. 51:53. 1893. 
5] 
13 [Botanical Gazette, vol. 42 
