2 DR. M. T. MASTERS ON THE 
some cases I have felt constrained to deviate from the arrange- 
ment there made, and to propose others which, according to my 
judgment, are more in harmony with ascertained facts or with 
more recently acquired information. Incidentally a few indi- 
cations of the structural peculiarities of certain parts, which 
may be available for purposes of distinction, are given, but any 
attempt to deal fully with comparative histology would be beyond 
the scope of the present communication. The writings of Ber- 
trand and of Van Tieghem may be specially pointed out as 
containing most valuable information on this head. Embryo- 
logical researches also are of the foremost importance from a 
classificatory point of view, but they demand for their prose- 
cution more time and skill than are at the command of the 
writer. It is, however, to systematic and comparative in- 
vestigation in these two departments, minute anatomy and 
embryology, that we must now look for future progress, but 
that progress will be retarded until the rigidly comparative and 
systematic methods by means of which the framework of the 
Natural System has been pieced together shall be carried out 
also in histology and embryology. And this remark applies as 
strongly to the methods in which these observations are recorded 
and published as to the observations themselves. Classifications 
founded on leaf-structure, on the distribution of the resin- 
canals and fibro-vascular bundles, or on the structure of the 
wood even, without reference to all other evidence, are neces- 
sarily as “artificial” as any other truncated schemes. 
For details concerning the structure of fossil species the reader 
will naturally refer to the publications of Williamson, Carruthers, 
and others. For the indications as to geological distribution I am 
chiefly indebted to Renault and Starkie Gardner. 
TAXACEAZ, 
Lindley, Vegetable Kingdom, ed. 3 (1853), p. 230. 
Arbores vel frutices. Rami plerumque homomorphi raro dimorphi. 
Folia persistentia raro decidua. Flores masculi amentiformes. Squame 
fructifere, ut videtur, simplices, liber, membranaceze seu demum carnosze 
nunquam lignosee. Ovula erecta v. pendula, e squama emergentes, aril- 
lata vel raro arillo destituta. Testa sicea seu demum carnosa nunquam 
alata. 
