172 PUCCINIA 
garden mint; perhaps those forms which are without it may hereafter be 
separated. But it has occurred on all the hosts mentioned above except 
Origanum and WM. rotundifolia ; it may, however, according to Sydow, be 
merely facultative. The form on C. Clinopodium really shows less difference 
from that on Mentha aquatica than those on species of Mentha do from one 
another. But Cruchet was unable to infect any one of the four Jf. arvensis, 
M. aquatica, WV. silvestris, C. Clinopodium, except by spores from the same 
species. As the result of his experiments, he divides P. Menthae into 
eight biological races, as it occurs on Mentha and Calamintha ; and the 
form on Origanwm is also biologically distinct. The Australian form of 
P. Menthae, which is an introduced species on UM. Pulegium and M. lax- 
flora, has no known ecidiospores, but occasional mesospores. Nothing 
seems to be known about the form on Ajuga reptans mentioned by 
Plowright, from Johnston’s Flor. Berwick. 
In garden mint (J/. viridis) the mycelium of the ecidial stage is spread 
throughout the whole plant, even in the rhizome; Klebahn was able to 
trace the hyphe in some cases nearly up to the growing point. It lasts 
for several years at least ; a bed of mint infested with it should be rooted 
up and burnt ; there is no cure for the disease, although I have found that 
cuttings taken from some of the more distant healthy-looking shoots and 
planted elsewhere grow up without the parasite. The mycelium of the two 
other stages is purely local. I have known the ecidia to occur for several 
years in a garden without being followed by uredo- or teleutospores so far 
as could be seen, and vice-versd, in another case, these spores occurred but 
no ecidium was ever noticed. 
DisTRIBuTION: Europe, Asia, Africa; the American and 
Australian teleutospores are-more strongly warted. 
44. Puccinia caulincola Schneid. 
Puceinia caulincola Schneid. in Jahresb. Schles. Gesell. 1870, p. 120. 
Sydow, Monogr. i. 301. Fischer, Ured. Schweiz, p. 172, f. 133. 
P. Schneideri Schrét. in Herb. Schles. Pilze, no. 448. Plowr. Ured. 
p. 201. Sacc. Syll. vii. 677. 
Teleutospores. Sori on the stems and petioles, rarely on 
the leaves, scattered, occasionally confluent, minute, roundish 
or elongated, long covered by the bullate epidermis, at length 
pulverulent, black, then cinnamon-brown; spores ellipsoid, 
rounded at both ends, apex sometimes thickened in a papilli- 
form fashion, rather constricted, smooth, pale-brown, 24—33 
x 15—24; pedicels hyaline, thin, rather long, not very 
