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supposed, but only two, so that the higher numbers exhibited in their ten- 
tacles and other organs are to be regarded as 2 x n, and he cites numerous 
examples which go far to establish his case. When uneven numbers occur, 
as in Hydra, for example, they are due to a certain amount of suppression or 
degradation ; thus, Hydra would have (2x4) — 1 = 7 tentacles. As the 
typical bitentaculate form, we have Atractylis bitentacidata cited, as in it the 
two tentacles are symmetrically placed ; Lar as well as Monobrachium are 
to be regarded as degraded forms, the former having 6-4 and the latter 4-3 
tentacles. The medusa of Lar is of a sex-radiate, and that of Monobrachium 
of a quadri-radiate type ; and the remaining two tentacles in the former genus 
are not placed symmetrically, but at an angle of about 60° to each other. 
Detection of Trichince. — M. Tikhomiroff suggests a new and easy method of 
detecting the presence of Trichince in suspected pork or sausages. The old 
method, consisting in the microscopic examination of slices of the suspected 
meat, may often lead to negative results, even when Tnchince are present 
in abundance ; the author proposes to isolate the muscular fibres, and states 
that their examination in this condition at once reveals the presence of 
Trichince. His process is as follows : — The flesh to be examined is cut with 
scissors into small fragments, soaked in distilled water, and then placed in 
a narrow-bottomed vessel with an approximately equivalent volume of 
chlorate of potash, and four volumes of concentrated nitric acid are added. 
The whole mass is then left for half-an-hour or more, and stirred occasionally 
with a glass rod. The fragments of muscle are then washed with distilled 
water, and put into a test-tube, one-third filled with distilled water, carefully 
corked, and shaken until the muscular tissue separates into its primitive 
bundles and fibres. The examination of these in a watch-glass, by the 
naked eye or with a lens, will immediately reveal the Trichince if present, 
as the fibres containing them at once attract the attention of the observer 
by the presence of fusiform swellings, whitish at the circumference, darker 
in the centre, along the primitive fibres. The microscope then easily tests 
the correctness of this rough investigation. — Bidl. Soc. Imp. Nat. Moscou, 
1877, No. 1. 
The Colorado Beetle. — This malevolent animal still continues to occupy a 
good deal of the public attention, although, after the many false alarms that 
we have had, it is really hard to say how far the outcry in Europe is 
justified. The little scourge has been honoured by a discourse by Mr. 
McLachlan at the meeting of the British Association. That gentleman 
upholds an opinion which has been commonly expressed by entomologists, 
that the beetle, if it comes to us at all, will come in a chance fashion, by 
flying on board shipping at one of the American Atlantic ports, where 
it is now abundant. Dr. Andrew Wilson has written a small pamphlet 
on the insect, published by Messrs. W. & A. K. Johnston, and illustrated 
with enlarged figures of the true Colorado Beetle and the <e Bogus Potato 
Bug ; ” this we have not seen, but we have been informed that it is good. 
— Messrs. Routledge have reprinted one of the admirable reports of 
Mr. C. V. Riley, of Missouri, from whose writings nearly all who have 
treated of the beetle have derived a very considerable part of their in- 
formation. Enlarged drawings of the beetle may be seen stuck up in the 
windows of newspaper offices, &c., in various parts of the town, and our 
