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gaining new advocates for the theory. The latest convert of importance is, 
we believe, Sir Roderick Murchison, who, at the recent meeting of the 
British Association, stated that 
“ He should not occupy tune by alluding to the engrossing subject of the 
most recent natural operations with which the geologist had to deal, and 
which connected his labours with those of the ethnologist. On this head he 
would only say, that having carefully examined the detrital accumulations 
forming the ancient banks of the river Somme in France, he was as complete 
a believer in the commixture in that ancient alluvium of the works of man 
with the reliquse of extinct animals as their meritorious discoverer, hi. Boucher 
de Perthes, or as their expounders, Prestwich or Lyell, and others. He 
might, however, express his gratification in learning that our own country 
was now affording proofs of similar intermixture, both in Bedfordshire, 
Lincolnshire, and other counties ; and, possibly, at this meeting they might 
have to record additional evidences on this highly interesting topic.” 
If, day by day, the telescope is enabling man to penetrate farther and 
farther into the dist ant heavens, and chemistry is rendering him cognizant of the 
constitution of the rolling orbs, so is the penetrating power of the microscope 
bringing within the range of his vision innumerable objects of beauty hitherto 
unknown to him, and investing the most commonplace subjects with fresh 
interest and wonder. Who would have dreamt that a piece of orange-rind 
could afford us opportunities for the study of entomology 1 But so it is. 
Mr. Richard Beck has imparted new interest to this one of the most ordi- 
nary of our imported fruits. 
He says ( Micr . Trans. 47) that, “ If the external surface of almost any 
of the sweet oranges be only cursorily examined, it will be found more or less 
spotted with small scales, the shields of a “ Coccus ” or scale-insect.* They 
are adherent to the rind of the orange, but can easily be detached ; and on 
turning one of the larger ones over, it will be found, on examination under a 
low power, to present as the most striking feature a large accumulation of 
eggs lying beneath a cottony secretion.” 
Mr. Beck has minutely described the metamorphoses of this curious little 
insect ; and he says that one single orange, if Avell selected, will supply every 
condition described by him. Many microscopists will, no doubt, be tempted 
to direct their attention to an interesting object so easily obtainable. 
Every day fresh additions are made to the list of those exquistely con- 
structed and mysterious microscopical forms the “ Diatomacae.” Several new 
species have, during the last few months, been described and delineated by 
Dr. R. K. Greville, Dr. Donkin, and George Norman, Esq. 
A few words more in regard to chemical science, and we must draw this 
imperfect review to a close. The question of the employment of Arsenic in 
colouring ladies’ dresses, head-gear, &c., has caused some stir, and on this 
subject an obliging correspondent sends us the following communication, 
which will no doubt be found interesting to our readers : — 
“ Green Colours. — Scheele’s, or the arsenical, green is in many respects 
a most objectionable and especially a dangerous colour. Eisner has intro- 
* One of the “ Hemipterous ” order of insects, of which the well-known 
Aphis may be considered the type ; and the family to which the cochineal 
insect belongs. 
