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attachment swells out into a large membranous crop, of the appearance of which, in the Octopus ventricosus, at least, I cannot give you a better idea than by comparing it, both in size and position, to the bulb of a small retort. The gizzard (fig. 55, 56.b) is a thick muscalar organ, like the gizzard of a fowl, and strongly corrugated internally in a longitudinal direction: immediately beyond it, in the Sèpia and Octopodiæ, is situated a curious spiral appendage, laminated on the interior, into which the bile is poured; but in the Loligo, instead of this spiral cæcum and, as it were, to compensate for its deficiency of a crop, there is a very large membranous and somewhat cylindrical bag (fig. 55, 56. c), on the posterior and upper part of which we trace vestiges of the spiral structure, for there a fatty substance is so disposed as to assumé that form, having the outer edges cut in a deeply serrated manner (fig. 55, 56. d). I have found this bag always filled with a grumous fluid, and it is undoubtedly the organ in which digestion is principally effected and completed; for it not only receives the bile, but is itself, or the spiral part of it, supposed to furnish a secretion analogous to that of the pancreas in higher animals. The aperture between the gizzard and this cæcum is oblique and valvular, and another adjoining aperture leads to the intestine (fig. 55, 56. + e), which, like the æsos phagus, winds upwards along the surface of the liver to terminate in the funnel, which is the common vent of all the excrements. The liver is very large in all the genera of this class, and must furnish a copious supply; but, besides this, and the secretions of the other accessary organs to good digestion, Sir E. Home believes that the inky fluid is intended also to have some effect upon the lower portion of the intestinal canal, to enable this to extract from its contents “a secondary kind of nourishment” (Comp. Anat., i. 369. and 393.); an opinion not very probable in itself, and with but a few fanciful analogies in its support.
* “ It may with greater propriety be denominated the duodenum, as it performs some of the offices of that part of the gut in the higher orders of animals. This stomach is conical, closed at the distal extremity, and performs about a turn and a half, like a spiral shell. Its inner surface is covered with a ridge, which traverses it in a closely spiral direction.”Fleming, Phil. Zool., q. 424.
+ In reference to these figures, it may be observed that they are copied from nature; a remark which seems necessary, since they differ entirely from Sir E, Home's figure of the stomach of Loligo vulgàris, or the Sèpia Loligo of Linnæus. Sir Everard's figure appears to have been taken from a species of Octòpus.
Art. IV. Observations on some British Sérpulæ.
By the Rev. M. J. BERKELEY. In an interesting notice of Sérpula tubulària Mont., by Dr. Johnston, in p. 126., a doubt is expressed whether S. tubulària Mont. and S. vermicularis of Authors have not been confounded in an article in the Zoological Journal, iii. 229. The truth is, that, at the time the article in question was prepared, my text-book for British conchology was Dr. Turton's Conchological Dictionary, as being the most recently published work upon the subject; and, throughout, where S. tubulària is mentioned, the species so named in that work is intended, which is not the same with S. tubulària Mont., but is S. triquetra Mont. Test. Brit., pt. 2. p. 511. (Tùbus vermiculàris Ellis, Corall. t. 38. f. 2.), but not Mont. Suppl. p. 157., which is the true S. triquetra. Though I was well acquainted with the several allied species and their distinctive characters, I confess freely that I was not then aware of the identity of Montagu's S. tubulària, with S. arundo Turt., and, in consequence, supposing Turton's species to have been first described by him, adopted his name.
The following synonymes, which I find written on the back of the rough copy of the article above mentioned, I shall beg leave to subjoin, as they may possibly be useful to others in the study of the common British species, whose nomenclature has been most unfortunately confused, though, at the time the Supplement to the Testacea Britannica was published, the species were well known to Montagu. The only alteration I shall make is the one suggested by Dr. Johnston, of the propriety of which there can be no doubt ; viz., that the older name of Montagu should be preferred to the more recent one of Turton. I am quite satisfied, on a careful examination of Turton's descriptions, that he had in view the species figured in Ellis, quoted above, for his S. tubulària, and the S. tubulària Mont. for his S. arundo. If not, the very common species of Ellis is altogether omitted; or, if S. vermiculàris of the Conchological Dictionary be supposed identical with it, the almost equally common species with a double infundibuliform operculum, figured by Müller, Zool. Dan., t. 86. f. 7–9. I shall only add to these observations, that S. tubulària Mont. ought certainly to be placed in a different genus from S. vermiculàris, &c., being altogether destitute of an operculum. According to the principles of Cuvier's Règne Animal, it belongs to the genus Sabélla, and is one of the rare instances in which a shelly tube occurs in that genus.
This has been proposed in a paper printed in No. xx. of the Zoological Journal, but not yet published.
The following are the synonymes alluded to above : Sérpula (Sabélla nob.) tubulària Mont.; Sérpula tubulària Mont. Test.
Brit. pt. 2. p. 513., Johnst. Mag. Nat. Hist. vii, 126.; Sérpula arundo Turt. Conch. Dict. p. 155., Berk. Zool. Journ. v. 3. p. 229., Tab. Supp.
xvüi, f. 2. Sérpula Múlleri nob.; Sérpula vermiculàris Mont. Test. Brit. pt. 2. p.
509., Mont. Supp. p. 157. (with reference to Zool. Dan. t. 86.), Turt.
Conch. Dict. p. 152. var. b. Lam. An. sans Vert. t. v. p. 362.
I am obliged to designate this species, which is characterised by the double infundibuliform operculum, by a new name, as, in the confusion of synonymes, I know not that there is any which can be unobjectionably applied to it. The name now proposed will have the advantage of calling attention to the figure of the animal in Zoologia Danica, and thereby prevent any confusion which might arise from the similarity of its shell to that of any other species. I have received from the Western Hebrides a species exactly resembling this as regards the testaceous covering, but furnished with two double infundibuliform opercula. Though the animal was preserved in spirits, it was so decayed that, unfortunately, I could not trace the connection of the opercula with the branchial fringe, and, therefore, do not venture to propose it as decidedly distinct. Sérpula vermiculàris Linn. ; Sérpula vermiculàris Lam. An. sans Vert.
t. v. p. 362.; Tùbus vermiculàris Ellis, Corall. t. 38. f. 2.; Sérpula tríquetra Mont. Test. Brit. pt. 2. p. 511, not Suppl. p. 157.; Sérpula tubulària Turt. Conch. Dict. p. 154. f. 84.
This species is distinguished from the following, in every stage of growth, by its corneous striated operculum. It is seldom found above the ordinary low-water mark. Sérpula triquetra Linn.; Sérpula triquetra Mont. Supp. p. 157, not
Mont. Test. Brit. pt. 2. p. 511., Turt. Conch. Dict. p. 152., Sow. Genera of Shells; Vermília triquetra Lam. An. sans Vert. t. v. p. 369.
This is perhaps the most common of all the British Sérpulæ. The operculum, which is testaceous, is very variable. Specimens occur in which the testaceous coating is a mere pellicle: but in this case there is no difficulty in distinguishing it from the foregoing species, as it is destitute of the
beautiful radiating striæ. Other forms of the operculum are described by Montagu, in the place quoted above, and figured by Sowerby in his excellent Genera of Shells. King's Cliff, Wansford, Northamptonshire,
July 19. 1834.
ART. V. On the Injury produced to Plantations of Sallows and
Osiers (Sálices), and Loss of Gain to the Proprietor, by the Ravages, on the Foliage of these Plants, of the Caterpillars of the Insect Nématus cùpree F.: with a Notice, in Sequel, of the very great Importance of a Scientific knowledge of Natural Objects to those engaged in the Practices of Rural Economy. By C. D.
I OBSERVE, in p. 265., a short notice of Nématus càpreæ. I am very little, indeed, of a naturalist; but, having suffered from the ravages of this insect, my attention has been drawn to its acts and habits; and the results of my experience may be, perhaps, useful to others. I have a piece of moist ground, in a low sheltered situation, highly favourable in itself for the growth of osiers. I remember it, as first known to me about thirty years ago, when some straggling osier bushes were growing upon it, and it was covered in other parts with weeds and brambles. On the offer of an opportunity, about twenty years since, I determined on cultivating the spot well, and then planting it with osier plants. A sort of tradition prevailed, that osiers would never succeed there. This I disregarded, deeming it absurd, since they grew freely in very inferior situations in the neighbourhood. The ground was thoroughly dug and then planted. After a few years, the osiers had disappeared, we hardly knew how. The spot was again planted, and with a like result. The ravages of the insect were now noticed, indeed, but still they did not sufficiently attract our attention; and osier plants were actually put in a third time. My attention being now strongly drawn to the subject, I discovered that which ought to have been perceived half a century sooner, namely, that Nématus càpreæ, favoured by the peculiar localities, was the cause of all this devastation. The spot is low, moist, shut in by wood, and very near the southern limit of England. The species of willow planted was chiefly one of those with broad leaves, woolly underneath.* The warmth of the situation, and the nidus for eggs afforded by these woolly leaves, were, I presume, the combined cause of the insect being so remarkably attracted to this spot. Some of the plants were of a species with smooth narrow leavest: these escaped much longer
* [Most probably the Sàlix càprea L. “ The name caprea seems to have originated in the reputed fondness of goats for the catkins.” - Smith. The specific epithet of the insect, Nématus càpreæ F., was doubtless intended to teach the fact, that the foliage of Salix caprea L., and, it may be assumed, that of allied species, as well (all called sallows in some parts of England), is the favourite food of this insect in the larva state.]
† (Salix triándra, amygdálina, Forbyana, rùbra, purpùrea, Hèlix, and Lambertiàna, are species of osier, natives of Britain : of this kind, the first four include the species more extensively cultivated in English osier plantations, called, in some places, holts.]
than the others, but still they did not escape eventually: they were also attacked by another caterpillar. I introduced both red and black ants, and also put some of the caterpillars into their nests; but the ants disregarded them altogether. Having, although thus slowly, ascertained the true state of things, the ground was once more cultivated, and was planted with apple trees. As there happens to be no insect there which much attacks these, they thrive very well. The distance at which apple trees are planted is also less favourable to the propagation of vermin. I have communicated all this detail, in order to show the importance, to individuals, of attending to such seemingly trifling matters. Many a plantation, &c., fails in an apparently inexplicable manner. A scientific investigation would, in numerous cases, disclose the truth, and prevent farther loss. Had a person acquainted with entomology been proprietor of this osier ground fifty years since, he would speedily have discovered the truth, and might have saved 200l. or more to himself and his successors. Wireworms. – I take this opportunity of mentioning the wireworm. This neighbourhood has been repeatedly ravaged by it. Crops of wheat and potatoes have suffered severely, but the pastures have never been touched. We have no old meadow, and our lands are always broken up when three or four years old. The beetle and its habits are not sufficiently known. If some popular knowledge on these destructive insects could be conveyed to farmers and labourers, they might, perhaps, be destroyed on a large scale. Penzance, June 18. 1834.
THE facts communicated by C. D. on the habits of the Nématus capreae are a welcome furtherance of our knowledge of the natural history of that insect; and they, in conjunction with C. D.'s remarks, are, we conceive, of emphatic value, as exemplifying to entomologists how much their aid in elucidating oil, the forms, structure, transformations, habits, and names of insects is wanted by persons engaged in the businesses of rural life, and also as intimating to them some idea of the extent to, and mode in, which the required aid should be rendered. A remembrance of the nature of our own wants in things entomological, as experienced while engaged in rural practices, and, added to this, some knowledge of the wants of others so engaged, tempt us, therefore, to join C. D. in soliciting entomologists (which C. D. does, in
effect) to do, forthwith, what they can, towards leading us, as