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78 the ordinary naturalist, who only consults such writings, when considered necessary, as one refers to a dictionary or cyclopædia. Certainly this volume requires study, and without dissections are made to illustrate its teachings, much of the labour of Mr. Mudge may have been expended in vain.

Chapters xx. to xxiv. can, however, be read with pleasure and instruction by any zoologist, for such topics as Embryology, Heredity, and Variation, among others, not only appeal to the consideration, but demand the attention of every naturalist, however little he may regard the philosophical side of his subject. The chapter on Heredity is a particularly fair and concise exposition of that phenomenon, and can be appreciated alike by the followers of Eimer and the disciples of Weismann. The difficulty of finding a theory impregnable from all attack may be well understood when we examine the nature of some statements which are advanced as fundamental facts. Thus Mr. Mudge, in his tabulation of the "chief differences between the Cockroach and a Butterfly," states of the last-named that its antennae are thickened "into a club at the tip," that the "fore wings are larger than the hind wings in both sexes," and that it "feeds, when it does so, entirely on honey which is obtained from flowers." Now these three statements are true in a general sense, but incorrect in an absolute one. In very many species of the Hesperiidæ, the antennæ are not clubbed; in the genus Dismorphia the posterior wings are larger than the anterior ones; while though it would be agreeable to believe that these beautiful creatures feed on honey alone, the fact remains that some of the most brilliant representatives are attracted by the dung of animals, offal, decomposing Elephant meat, dead Stoats and Weasels, and, as Sir H. Johnston has informed us, even, like ghouls, by the blood-soaked ground after a human combat.

less an authority than John Addington Symonds has stated that the reputation of Sir Thos. Browne is founded