Fretter v (56 résultats)

Soft cover. Etat : Very Good. Supplement 16 The Journal of Molluscan Studies 1986 - this copy would have been listed as Near Fine were it not for a spot of abrasion to the back cover. The rest of it is in excellent condition with clean white pages throughout, setting off the beautiful drawings and photographs.…

Etat : Good. This is an ex-library book and may have the usual library/used-book markings inside.This book has hardback covers. Clean from markings. In good all round condition. Dust jacket in fair condition. Please note the Image in this listing is a stock photo and may not match the covers of the actual item,1000grams, ISBN.…

Etat : Fair. This is an ex-library book and may have the usual library/used-book markings inside.This book has hardback covers. In fair condition, suitable as a study copy. Re-bound by library. Please note the Image in this listing is a stock photo and may not match the covers of the actual item,1700grams, ISBN.…

22pp, 10 figs, Printed card cover, VGC.

18pp, 4 figs, Printed Card Cover, VGC.

22pp, 4 figs, Printed Card Cover, VGC.

20pp, 5 figs, Printed Card Cover, VGC.

As regards anatomy and histology the alimentary canals of Elysia viridis, Limapontia capitata and Hermaea dendritica are very similar and exhibit specializations for manipulating their filamentous algal food. The mouth leads through an oral tube to a small vestibule ventral to the anterior tip of the odontophore. Into the vestibule and the tube open subepithelial glands which secrete mucus and adhesive substances. The vestibule leads into the dorsal part of the buccal cavity containing the odontophore. This is lined by a cuticularized epithelium and muscles?-striped in Hermaea?radiate from the basement membrane or from the cuticle. The buccal cavity with its thick muscular walls acts as an organ for sucking into the alimentary canal the contents of plant-cells. The salivary glands open by ducts into its posterior part, behind the opening each duct swelling into a muscular vesicle which acts as a pump. The saliva probably contains enzymes. The oesophagus, ciliated and glandular, passes to the stomach. In Elysia and Herma a muscular oesophageal pouch is developed which assists in the transport of food along the gut. The small stomach, of little physiological significance, receives the wide ducts of the digestive gland. In Elysia these open into the left and mid-posterior walls. In Limapontia and Hermaea the posterior part of the stomach opens freely into the main tubules of the gland, which are sufficiently wide to accommodate sudden inflows of food pumped from the oesophagus. Owing to the type of food, from which the faecal matter is inconsiderable, and the total absence of a mantle-cavity, there is no necessity for extensive arrangements to elaborate the faecess; consequently the intestine is short and, except in Hermaea, without glands. The gut and the nervous system show greater resemblances to those of the Lophocercidae and Diaphanidae than to those of the other groups of nudibranchs. It is therefore in the primitive groups of the tectibranchs that the origin of the Ascoglossa is to be sought. 14 pp., 2 figs, br. gr. 8.…

Hardcover. Dust Jacket Included. pp.xvi, 755 with b/w. fine anatomical illus., throughout. Large 8vo. Ex-lib. Thor. vg. hardback in good dw.

Etat : good. A copy that has been read, remains in good condition. All pages are intact, and the cover is intact. The spine and cover show signs of wear. Pages can include notes and highlighting and show signs of wear, and the copy can include "From the library of" labels or previous owner inscriptions. 100% GUARANTEE! Shipped with delivery confirmation, if you're not satisfied with purchase please return item! Ships via media mail.…

Etat : Very Good. Former library copy. Pages intact with possible writing/highlighting. Binding strong with minor wear. Dust jackets/supplements may not be included. Includes library markings. Stock photo provided. Product includes identifying sticker. Better World Books: Buy Books. Do Good.

Etat : Fair. This is an ex-library book and may have the usual library/used-book markings inside.This book has hardback covers. In fair condition, suitable as a study copy. Library sticker on front cover. Please note the Image in this listing is a stock photo and may not match the covers of the actual item,1850grams, ISBN.…

Etat : Very Good. 820, 341 figs. . HB. Vg in d/w. From the library of Prof. J. Green (1928-2016) with his name to endpaper. Second edition, revised and updated. [9780903874236].

Etat : Good. This is an ex-library book and may have the usual library/used-book markings inside.This book has hardback covers. In good all round condition. Re-bound by library. Please note the Image in this listing is a stock photo and may not match the covers of the actual item,1500grams, ISBN:0122675509. …

52 pp., 130 figs, br. gr. 8.

Imperial octavo, green heavy boards, gilt lettering to spine, gilt insect illus to front board, vi + 589pp, illus, VG+ (light bruising to board edges/extrems, light foxing to page edges & eps, prev. owner's name in ink to ffep) in d/w, VG- (price clipped, moderate creasing & chipping with some minor loss to edges, light tanning to spine, light chafing & soiling).…

40 pp., 7 figs, nr. gr. 8.

The reduced right half of the pallial complex of Nerita tessellata, N. fulgurans, N. versicolor, N. peloronta and Neritina virginea comprises a hypobranchial gland, a vestigial gill and the opening of a duct which bears the same relationship to this gill as that of the left kidney to the functional gill. The duct leads from the region of the genital duct corresponding to the renal section of mesogastropods. The posterior part of the glandular genital duct lies in the visceral mass; its relationships are identical with those of the left kidney. The anterior part develops alongside the rectum within the anterior pallial vein. The left half of the pallial complex of Nerita includes a hypobranchial gland absent in Neritina and Theodoxus. The floor of the mantle cavity of Nerita forms an accessory respiratory surface, receiving blood from the anterior aorta. Its blood spaces communicate with the haemocoel and the parabranchial vein. This vein, also present in Neritina and Theodoxus, drains the mantle skirt. In Nerita its importance increases when the snail is out of water and the mantle cavity is used as a lung. The buccal mass of Nerita fulgurans has the same basic organization as that of Monodonta lineata: differences are related to specializations in the neritid radula requiring greater versatility of movement during feeding. It is protruded by lateral and ventral protractor and buccal depressor muscles originating on the body wall and inserted on the posterior radular cartilages. The horns of the anterior cartilages are orientated to the feeding ground by an array of levator muscles unparalleled in the trochid, and by the buccal fold which also spreads the radula and ensures its maximal sweep. The radular membrane is pulled outward by protractor muscles originating on the posterior cartilages and associated with a cartilage in the posterior wall of the sublingual pouch. Food is gathered on the back stroke of the radula which is drawn into the buccal cavity by a powerful retractor muscle associated with a radular diverticulum. The diverticulum is absent in trochids which have muscles for direct retraction of the buccal mass. The absence of salivary glands in neritaceans may be related to the development of the buccal fold; glandular buccal pouches and sublingual glands may compensate for their loss. The oesophageal glands extend through the anterior oesophagus to the buccal cavity; owing to their separation from the mid-oesophagus they are unaffected by torsion. The stomach is a voluminous sac, simplified in that the caecum is lost or vestigial and that the major typhosole ends at the junction of the style sac with the proximal region. The gastric shield forms a tooth, very prominent in Neritina, which can protect the openings of the oesophagus and ducts of the digestive gland. 29 pp., 11 figs, gr. 8.…