572 
POPULAR SCIENCE REVIEW. 
regularly exists in the red corpuscles of oviparous vertebrata^ 
such nucleus is as regularly wanting in the red corpuscle of 
Mammalia. Hence the divisions Vertebrata pyrencemata and 
Vertehrata apyrencBmata.^ 
Little use has been made in descriptive botany of the dis- 
tinctions afforded by intimate structure in allied flowering 
plants ; and my own observations had not been long prose- 
cuted when many examples were found of the truth of 
Schleideffs remark as to how little hope there is, without 
a study of the fundamental principles of development, of 
much further aid to systematic botany from mere anatomy. 
Yet it soon appeared tiat minute anatomy would occasionally 
afford good diagnoses in the pith-cells, leaf-cells, or pollen, 
between some species of one genus of such vascular plants as 
Juncacece,-^ Symenophyllece,% smd Rcumnculece and it was not 
before a large heap of my notes had been collated, that 
raphides were at all thought of in this point of view ; for 
they had not been particularly looked after, having been 
merely noted as they happened to be seen, long before their 
significance as natural characters was even suspected. But 
when all those notes of raphides had been picked out, it was very 
unexpectedly discovered that they would come under certain 
orderly arrangements. Thus not a single instance of any species 
belonging to the orders Onagracece and Galiacece was without 
a note of raphides ; while of the neighbouring orders raphides 
were noted in no species whatever. And, conversely, a single 
order, e.g., Hydrocharidacece, in which raphides were never 
seen at all, would be surrounded by orders in which raphides 
ever appeared abundantly. Thus it was that this subject 
forced itself on my attention ; and then repeated experimental 
trials soon proved that raphis -bearing is an essential and in- 
trinsic, a distinct and characteristic phenomenon throughout 
the life of certain plants, and withal clearly a sure and constant 
result of that life ; while the same character was as constantly 
wanting in still more plants. Raphides were proved to exist' 
in the ovule, || to be always present in the seed-leaves, and 
thenceforth throughout the leaves and a large part of the inter- 
texture of the frame of the species belonging to such orders 
as Onagracece. Hence the inquiry was continued, with the 
results of which the present memoir contains an epitome. 
College Lectures, reported in Medical Times and Gazette, 1862-63 ; and 
the “ Hunterian Oration ” for 1863. 
b Annals of Natural History, December, 1863, plate VII. 
X Ibid., October, 1863, and Seemann’s Journal of Botany, same date. 
§ Annals of Natural History, ser. 3, vol. xvi. 
11 Annals of Natural History, November, 1863, fig. 1, p. 366. 
