Algae. — Pflanzenkrankheiten. 
259 
Fucus vesiculosus und Ascophyllum nodosum nur die letztgenannte 
Alge von Polysiphonia fastigiata bewohnt wird Dieser Epiphyt sie¬ 
delt sich in erster Linie in dem Grunde der Sprosswinkel an. Erst 
später wird auch die Breitseite des Thallus besiedelt. Die Rhizoiden 
von Polysiphonia dringen zwischen die Rindenzellen von Ascophyl¬ 
lum ein. Die Rindenzellen sind in vertikaler Weise angeordnet und 
sind oft durch Spalten von der Oberfläche aus zerklüftet. Vielleicht 
findet besonders in diesen die Ansiedlung des Epiphyten statt. 
Möglicherweise liegt auch echter Parasitismus vor. Der Umstand, 
dass die Alge auf Ascophyllum und nicht auf Fucus vorkommt, 
lässt sich aus dem Fehlen der Sprosswinkel bei Fucus und der 
nicht vertikalen Anordnung der Rindenzellen bei letzterem erklären. 
Heering. 
Pool, V. W., Some Tomato Rots during 1907. (21 st An. Report 
Nebraska Agr. Exp. Stat. p. 3—33, 10 plates, Lincoln 1908.) 
An account of various rots of the tomato prevalent during the 
season of 1907 is here presented. Several new characters of several 
of these rots were noted although no new species were made. The 
varieties of tomatoes concerned were =: Dwarf Champion, Stone, 
and the Wonder Magnus. The following rots werestudied : Alternaria 
fasciculata (C.&E.) Jones and Grout; Rhizoctonia sp. which resembles 
somewhat Corticium vagum B. & C. and which it may be; the ripe 
rot or anthracnose, Colletotrichum lycopersici Chester.; Fusarium 
solani Mart, and Fusarium sp. These are treated under the following 
heads; symptons, isolations and inoculations, description of the 
fungus, historical etiology, and cultural characters. Preventive mea- 
sures are also suggested among which are: train the vines to secure 
free access of air and sun; iremove infected parts, Bordeaux 
mixture applied every two weeks during the growing season. 
R. J. Pool. 
Rolfs, R. H. and H. S. Fawcett. Fungus Diseases of Scale 
Insects and White Fly. (Florida Agr. Exp. Stat. Bull. XCIV, 
pp. 17. figs. 21. July 1908.) 
The climatic conditions of Florida are especially favorable for 
the spread of all fungi making it readily possible to combat insect 
pests by means of fungus diseases. The use of such fungi is in no 
way injurious to the plants infected by the insects because they do 
not attack the plants at all. The care necessary for success in the 
use of this means of control of scale and white fly is emphasized. 
During the most favorable weather it takes about four weeks for 
the fungi to spread sufficiently to be noticed by the unaided eye. 
Sphaerostilbe coccophila Tul., the red-headed fungus, is described 
and figured followed by notes on the genera and species of insect 
attacked and direction as to how to apply the fungus. Ophionectria 
coccicola E. & E., the white-headed fungus and Mynangium duriaei 
Mont., the black fungus, are treated in the same way. All three 
fungi attack various species of scale insects. The method of appli- 
cation is simply to tie sticks bearing the fungi in contact with the 
twig infected with the insects. The spores are washed about over 
the surface of the plant and gain entrance to the insects. 
The yellow fungus of the white fly, Aschersonia ßavo-citrina, 
and the red fungus of the same insect, Aschersonia aleyrodis Webber, 
are treated after the same outline as the above species. A few notes 
are given on the brown fungus of the white fly. R. J. Pool. 
