1 74 
Advanced Lectures in Botany. 
is necessary. It forms a particularly good constrast stain with 
iron alum-haematoxylin for the nuclei. Material fixed in alcohol 
or acetic alchohol stains the most readily and effectively; it also 
works very well after fixing fluids containing chromic acid only, but 
then the stain takes somewhat longer and is not quite so bright. The 
rapidity of the stain and the density of the result are increased by 
the addition of a few drops of ammonia to the solution, a modi¬ 
fication which is specially helpful in treating refractory chromic 
material. The stain fades very quickly in ordinary xylol-canada- 
balsam, probably owing to a slight acidity of the medium (neutral 
balsam was not tried), but it keeps very well in xylol-dammar and 
in gum-thus. 
The effect of such a stain does not necessarily mean that the 
cell-wall in the Uredineae consists largely of cellulose, for the value 
of Congo-red as a test for this substance has been called in 
question by the observations of Heinricher and Challon. 
V. H. Blackman. 
UNIVERSITY OF LONDON ADVANCED LECTURES. 
[Owing to an oversight all reference was omitted, in the note 
under the above title in the last number of this journal, to Dr. 
Rendle’s Course on Tubiflorae given contemporaneously with Dr. 
Blackman’s on C0 2 -Economy. Dr. Rendle’s Course was delivered 
at the Chelsea Physic Gardens. The following is a brief notice of the 
scope of the Course]. 
The subject of the lectures was the Cohort Tubiflorae as 
recognised in Professor Engler’s syllabus. The introductory 
lecture included a discussion of the position of the cohort as a 
member of the great group of Dicotyledons, the Metachlivnydene. 
It was pointed out that while there was considerable evidence in 
favour of a polyphyletic origin of the group, there was a very 
general opinion that, at any rate, Tubiflorae must remain as repre¬ 
senting a number of nearly allied orders standing somewhere 
near the top of the Dicotyledonous tree. The orders were then 
taken seriatim, and their morphology, vegetative and floral, the 
principles of their sub-division into tribes and genera, and their 
geographic distribution were studied with the help of a large series 
of lantern slides, of living specimens grown in the Chelsea Gardens, 
and also of wild British examples. It was seen that, although 
there might be some difficulty in separating the constituent orders 
in distinct cohorts, it was possible to recognise several more of less 
well-marked sub-divisions. Starting with Convolulaceae and Pole- 
moniaceae we pass from a radially symmetrical flower, in which 
moreover the bicarpellary character has not become so rigidly set, 
through Hydrophyllaceae, Boraginaceae and Solanaceae, where 
the tendency towards zygomorphy is increasingly marked, to the 
still more specialized members of the group represented by 
Scrophulariaceae and its (often very) closely allied orders, Acan- 
thaceae and Labiatae. Constant reference was made throughout 
to cross affinities and the recurrence of closely similar types of 
floral conformation in different orders, doubtless associated with 
the adoption of similar methods of pollination. 
R. HADLEY, PRINTER, WHITFIELD STREET, LONDON, W. 
