It has always been difficult to account for the widely-spread nature of outbreaks of wheat mildew in districts in which the common barberry is either entirely absent or very uncommon. In the year 1874 the Rev. James Stevenson found at Glamis, in Forfarshire, an Æcidium upon
Mahonia aquifolia
, which the Rev. M. J. Berkelev pronounced to be
Æcidium berberidis
. In the following year Dr. Paul Magnus found the same fungus at Lichterfelde, near Berlin, but since that time it does not seem to have been noticed by any one. On the 31st of May, 1883, Mr. William C. Little, of Stagsholt, March, gave me a freshly gathered specimen of
Mahonia aquifolia
, upon the berries of which the Æcidium was abundant. Knowing that upon the barberry no less than three different AEcidia occur, I determined to prove by direct experimental culture whether this one was the
Æeidium berberidis
of Persoon (the æcidiospore of
Puccinia graminis
). At 10 p. m. on the evening of the 31st May I placed some of the spores upon the cuticle of some wheat-plants which had been cultivated under a bell-glass. In eleven days the uredo of
Puccinia graminis
made its appearance upon these plants. The details of this, as well as of two other experiments, are appended. On the 13th June I placed some of the secidiospores upon a piece of wheat cuticle; in twelve hours they had germinated, and a little later the germ-tubes were seen entering the stomata, in the same manner as those of
Æcidium berberidis
do (see figure). It is then clear that the Æcidium upon
Mahonia aquifolia
is identical with the
Æcidium berberidis
(Pers.), and is a part of the life-cycle of
Puccinia graminis
, and is unconnected with the
Æcidium magellanicum
(Berk.), and the Æcidium of
Puccinia berberidis
(Mont.). The Mahonia in question is widely cultivated in gardens throughout England and is a favourite evergreen in shrubberies. It is also extensively planted in woods as a covert for game.
Growth and life cycle of the common cuttlefish Sepia officinalis L. (Mollusca: Celaphapoda) in Bouzedjar bay (Western Algerian Coast)
