306 
POPULAR SCIENCE EEYIEW. 
curve so as to describe the half of a circle. The lohing of the lower lip is 
various. In some cases the two lateral ones spread away from the small cen- 
tral one, leaving a free space all around it : at other times they overlap the 
central one, so that it is scarcely seen. Sometimes the small central lobe is 
nearly wanting — often not more than half the depth of the two large lobes, 
and at times quite as full, when it may be linear, ovate, or nearly orbicular. 
The palate, as the deep coloured process attached to the lower lip may be 
called, also varies. In colour it is pale lemon, but often a brilliant orange. 
Sometimes it is but about the eighth of an inch in thickness ; at others one- 
fourth, in flowers of the same size. In the case of the shallow flat palate, 
the attached lobes are patent, or even incurved 5 while in the thick ones they 
are very much reflexed. These two forms, when the extremes are selected, 
are as strikingly distinct as two species often are. Again, the palate is 
rounded and blunt at the apex ; at other times almost wedge-shaped, or at 
least narrowing to a blunt point. The upper lip varies in proportionate 
length, sometimes not extending much be5"ond the palate, sometimes half an 
inch more ; then the margins are sometimes bent down like the wings of a 
swooping bird ; or upwards as in those of a rapidly descending one. Some- 
times they are united and turned abruptly up at the apex, like the keel of 
the garden pea. 
The Structure of the Cystidia . — This is discussed very fully in Mr. Cooke’s 
Grevillea (June), in a translated paper by M. A. de Bary. The structure of 
the cystidia, he says, offers a few peculiarities ; in the greater ,part a deli- 
cate and colourless membrane surrounds sometimes a similarly colourless 
plasma, full of vacuoles, and sometimes a perfectly transparent liquid. He 
has observed in the hymenium of Coprinus micaeeus which had not yet at- 
tained its maturity, that the cystidia enclosed a central plastic body, irregu- 
larly elongated, which sent in all directions towards the sides of the cell a 
multitude of filiform processes, branching and anastomosing amongst them- 
selves. These processes changed their form with astonishing rapidity, after 
the manner of the Amoehce. The older cystidia were entirely transparent. 
The contents of the cystidia of Lactarius deliciosus, and allied species, are 
granular and opaque. In this respect the cystidia resemble the laticiferous 
tubes or filaments, and often when a thick slice of the substance of the 
fungus is observed, it seems that they are branches from these filaments, the 
more so since they bury themselves deeply in the weft of the lamellae, under- 
neath the subhymenial tissue. Still he has never seen them spring except 
from filaments of the weft deprived of latex, of which they seemed to be 
branches. The cystidia of Agaricus halaninus, Berk., are of a dark purple 
colour. According to Corda and the uncertain opinions of anterior authors, 
the cystidia eject their contents under the form of a liquid drop and that by 
their summit, which is represented as open. He has not, any more than 
M. Hoffmann, been able to convince myself that this phenomena is produced 
spontaneously. He has, indeed, only very rarely seen the cystidia burst in 
the water, which the same author says takes place very irregularly. If their 
surface is damp, and often bears liquid drops, this is a circumstance which is 
common to them with all fungoid cells that are full of juice. 
The Ehenacece : a ve^'y large family. — Mr. W. P. Hiern has published in 
the Transactions of the Cambridge Philosophical Society,” a most elabo- 
