356 Mr. A. Henfrey on the Vegetable Ovule. rugiceps ; but there can be no doubt, from the figure and descrip-tion, that it is the Vperodon ornatum of Mr. Bell, which is figured in the Zoology of the Beagle, p. 50. t. 20. f. 6. Dr. Hallowell, in a paper in the same volume, describes and figures some Snakes as new, which Dr. Gunther informs me are well-known species, described many years ago, thus : — Zamenis tricolor, Hallow. = Herpetodryas margaritiferus, Schleg. Elapoidis fasciatus. Hallow. = Streptophorus Sebae, Dum. Sf Bibr. XXXIII. — On the Relation of the Raphe to the Coats of the Vege-table Ovule. By Arthur Henfrey, F.R.S. &c. In the last number of the 'Annals' appeared a paper by Mr. Miers explanatory of his views on the subject named in the heading of this note. A clear statement of opinion is most valuable for the settlement of debated questions ; and the setting-out therein of the premises on which all the reasoning depends, is just what is required for the decision of the value of the arguments in the present case. These premises appear to us open to adverse criticism, taking away the principal grounds of the subsequent arguments. We will consider them seriatim, as laid down at pages 276-8. 1. That "vegetable growth in all its stages is regulated by the ordinary laws of mechanical action,'' is incorrect if taken without qualification, since all the peculiar phsenomena of organic development are indications of the action of a special force mo-difying the effects of simple mechanical laws ; but this question has no important bearing in the present case. 2. It is by no means true that every tunic of an ovule is formed of three elementary parts, epiderm, mesoderm, and endo-derm. No such distinction of parts occurs in the ovules of Orchis and many other plants, where the ovules are composed of comparatively small quantities of cells. 3. Communication of vessels can only take place between one tunic and another at points where they are organically continuous. 4i. The organic communication of the first and second tunics, testa, and tegmen, is usually confined to the vicinity of the chalaza or gangylode. 5. In erect ovules the chalaza is, of course, contiguous to the hilum. 6. In anatropous ovules the chalaza is removed from the vici-nity of the hilum ; but the inversion of the ovule takes place by a one-sided development of the tunics of the ovule, — of the single coat where only one exists, of the outer coat where two exist ; and the cord of vessels lying in what is called the raphe is organically
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