41 
ON TWO SUPPOSED SPECIES OF OVULARIA. 
By Ernest S. Saumon, F.L.S. 
(Puare 469.) 
In 1861, in Rabenhorst’s Fungi a No. 800, the rem 
name was published for a Hyphomycetous fungus :—** Crocisporium 
fore Bonord, Spec. nh Mspt. Hyphas smate ‘clivaeiiing "effasd 
; sporis magnis ovato-oblongis (nonnullis cylindricis tian 
rotundati is); hyphis psi septatis subcylindricis, apice sporas 
singulatim exserentibus ; ; ‘mycelio fneiemeem in superficie folior. 
repente. Hab. in foliis Viciarum, Guestphalie 
To the above diagnosis Bonorden added the following remarks :— 
“Der Pilz erscheint beim ersten Blick wie Torula monil. (Acro- 
sportum Nees, Oidium sky. wenn deren Sporen abgefallen ty 
nig findet aber niemals mehre Sporen kettenformig verbunde 
ondern immer nur or e an der Spitze der nach oben oft obiian 
dickat of nx cos Hyp 
In 1 t Besorden: te a further account* of the fneans re- 
‘naps: sek it sn a delicate, flocculent, greyish-white layer on 
living leaves of peas and other plants, and that it resembles very 
e mildew T orula moniliotdes, but that it is quite distinct, 
since sae ont conidiophore constantly bears only one spore—a cha racter 
which seldom occurs in the oat Bonorden remarked further 
that the figures given int von Mohlt of petro iret and those 
given by Preuss? of O. lew siscbdne ‘um show se fungi are the 
same ; and added that the appressoria eatorban noted by von 
Mohl on the mycelial hyphe of O. Tuckeri had been observed by 
him also in the case of C. fallar. Bonorden mentions also that 
von Mohl stated that he observed that in the examples of O. Tuckeri 
seen by him in the spring of 1853 the conidiophores bore, almost 
without exception, a single spore at the apex, while the same fungus 
in the autumn of 1851 produced conidiophores which bore usually a 
chain of 2-8 spores. From this observation of von Mohl, Bonorden 
contended that the fungus found in 1851 was a true “ Torula 
Oidium),”’ but that the fungus seen in 1853 was his C. fallax, 
“ Hiernach glaube ich nun das sogenannte Oidium Tuckeri, welche 
mit O, rire Desmaz. iibereinstimmt, richtiger Crocysporiwm 
zu nennen und zwar habe ich es C. fal/ax genannt, weil es seinem 
ganzen Habitus ‘tat und auch beim ersten Blick unter dem Mikro- 
skop sehr leicht fiir ein Oidium gehalten 
In the Sylioge Fungorum § (1886) Saceardo Est kept up Bonor- 
den’s specie a rring it to the genus Ovularia. 
tion of Bonorden’s plant awe at once that it is 
nothing fa than tho. conidial stage of Erystphe Polygoni DC., the 
species of ponte mildew so common on peas, vetches, &e. 
* Bot. Zeit. xix. 201, 202 (1861). { Sturm, Deutschl. Flora, iii, Taf. 34. 
+ Ibid. xi. Taf. xi. (1853), - § Vol. iv. p. 141. 
Journat oF Borany.—Von. 43, ee 1905.] : 
