NEW PUBLJCATIONS. 57 
But we have before alluded to the odd manner in which Mr. 
Clarke's own facts sometimes contradict his own positive assertions ; 
and it may be that the explanation is to be found there; the blindness 
and the falseness being in his own observations, not in the method so 
freely denounced in its results. The census scale in the ■ Cybele 
Britannica ' is found in volume iv. pages 234-273. The species placed 
in the first class of frequency, the first group in the series from com- 
monest to rarest, amount to 120, which have been ascertained to 
occur in all the 38 chief districts, and varying in the minor sections 
from 99 to 76. That list of 120 species has been collated with the 
' List of Andover Plants,' and our readers will perhaps feel some of 
the astonishment above attributed to " beginners " on being: told that 
no less than 119 of them are actually enumerated by Mr. Clarke 
among the plants seen by himself in one single habitat, to wit, within 
five miles of Andover. The one species which is omitted from the 
Andover list, and thus remains to represent the " many " species which 
Mr, Clarke has failed to detect while " walking about much in very 
varied parts of Britain," is Erica Tetralix — neither rare nor incon- 
spicuous. Evidently there is some considerable mistake, the facts 
being so utterly inconsistent with the positive assertion. Possibly Mr. 
Clarke wrote his strictures at Calcutta, without access to a copy of the 
1 Cybele Britannica,' and has thus fallen into error of statement through 
trusting to memory alone. We suggest the explanation, though 
scarcely holding it to be a sufficient excuse. 
Another difficult and much debated problem in plant-geography also 
finds its solution from the pen of Mr. Clarke; namely, how to dis- 
tinguish the indigenous from the introduced species in Britain, — how 
to eliminate those originally placed in Britain by natural agencies from 
those which have subsequently been introduced into the island by the 
hand of man. Our courageous author cuts the Gordian knot at once, 
and in the simplest personal manner. " All plants in this list," he 
writes, "not stated to be ballast plants, weeds of cultivation, or garden 
weeds, are to be understood as considered indigenous. By an 'indi- 
genous plant ' I mean a plant which I should expect to meet with if I 
were transported backwards to the period immediately before agricid- 
ture was commenced." Very simple this, and doubtless quite a satis- 
factory definition to the author himself. But how are Smith and Jones, 
English botanists seeing only the presently existent flora of Britain, to 
