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ORIGIN OF LIFE IN AMERICA 
the essential unity of the area inhabited by the snail Placo- 
stylus,* thus regarding New Zealand and the archipelagoes of 
Solomon, Fiji, New Hebrides, Loyalty, New Caledonia and 
Lord Howe as portions of a shattered continent which he 
called the “ Melanesian plateau.” The short review on the 
subject by Dr. Holdhausf in favour of a Pacific Continent in 
Tertiary times adds little to the arguments already advanced 
by Professor Baur. 
A most determined and thoroughgoing onslaught on the 
theory of a supposed former Pacific Continent was recently 
made by Mr. Guppy. It seems scarcely fair to compare the 
results of his studies with those just alluded to, because 
he derives his arguments almost altogether from the flora 
of the Pacific islands, while the others were founded on 
faunistic data. Still, Mr. Guppy’s works iji contain a great 
deal of personal observation, and his careful labours in 
this particular field of enquiry will be sure to attract 
the serious attention of the student of geographical dis¬ 
tribution. His discussion of the subject is disappointing 
in some respects. “ If the distribution of a particular 
group of plants or animals does not accord with the pre¬ 
sent arrangement of the land,” he remarks, “ it is by far 
the safest plan, even after exhausting all likely modes of 
explanation, not to invoke the intervention of geographical 
changes.” A little further he explains “ I scarcely think 
that our knowledge of any one group of organisms is ever 
sufficiently precise to justify a recourse to hypothetical altera¬ 
tions in the present relations of land and sea.” In reading 
such passages one wonders whether Mr. Guppy can have 
becomo acquainted with the science of geology, or with the 
principles that underlie the geographical distribution, for 
example, of mammals. His opinions differ radically even from 
those of Dr. Wallace, who cannot be said to have been unduly 
rash in any of his conclusions as to former changes of land 
and water. One would also expect from Mr. Guppy an abun¬ 
dance of important facts concerning the dispersal of seeds 
by the various means of accidental transport. But he tells us 
* Ilctlley, C., “ Range of Rlacostylus,” p. 339. 
t Holdhaus, K., “ Argumente f. d. Existens eincs pazif. Ivontinents.” 
f Guppy, II. B., “A Naturalist in the Pacific,” I., p. 380. 
