Purchon r d (13 Ergebnisse)

Zustand: Good. 2nd. Pages intact with minimal writing/highlighting. The binding may be loose and creased. Dust jackets/supplements are not included. Stock photo provided. Product includes identifying sticker. Better World Books: Buy Books. Do Good.

Hardcover. Zustand: Fair. No Jacket. Missing dust jacket; Readable copy. Pages may have considerable notes/highlighting. ~ ThriftBooks: Read More, Spend Less.

No Binding. Zustand: Very Good. ORIGINAL1948 reprint/offprint of journal article; no covers issued; light browning of leaves; o/w in very good condition. Journal.

Hardcover. Zustand: Very Good. Dust Jacket Included. pp.xxv, 560 pages, with 185 illustrations, a very good hardback in a very good dust-jacket, ex-library - a book in the International Series of Monographs in Pure and Applied Biology [0080126464].

Reprinted from Proc. Zool. Soc. Lond. Vol. 135, Part 3, 1960, 17,50x25,50 cm, broché, 60 pages Bon état - Pour les envois hors de France, la tafication «livre & brochure» pour les frais de port a disparue.Les frais de port annoncés correspondent à une moyenne. Ils seront calculés au plus juste en fonction du poids de votre article.…

Zustand: Poor. Volume 57. This is an ex-library book and may have the usual library/used-book markings inside.This book has hardback covers. In poor condition, suitable as a reading copy. No dust jacket. 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,1200grams, ISBN:0080210287.…

1. Detailed studies have been made of the structure and function of the stomach in the two protobranchs, Nucula nucleus L. and Nuculana minuta (Müller). 2. The structure of the stomach in the Protobranchia was described and figured, and defined as Stomach Type I. 3. The stomach of the septibranch Cuspidaria cuspidaia (Olivi) was similarly examined, described and figured, and was defined as Stomach Type II. 4. The stomachs of the Protobranchia and Septibranchia were compared and it was noted that there were several common features. Further resemblances were found in the structure of the digestive diverticula, and in the muscular pumping of water by the ctenidium (Nuculana) or by the septum (Cuspidaria). 5. It was concluded that there is a strong suggestion of phylogenetic relationship between the Protobranchia and the Septibranchia. 6. The view, previously stated by Yonge, that there was no justification for linking the Protobranchia and the Arcacea in an order Taxodonta was upheld. 15 pp., 5 figs, br. gr. 8.…

1. Healthy specimens of Martesia striata L. were obtained from timbers in the Johore Straits in March 1953, and were examined immediately. 2. The siphonal process is of type "C" and resembles that of Pholadidea loscombiana. 3. The shell valves possess a posterior flexible uncalcified portion, comparable with the siphonoplax of Pholadidea loscombiana. 4. The scar of the anterior adductor muscle is smaller than that of the posterior adductor. In this respect Martesia resembles Pholadidea more closely than other genera in the Pholadidae. 5. In large specimens which had ceased to bore, the pedal muscles and the anterior and posterior retractor muscles of the visceral mass had atrophied. The foot also had disappeared. 6. The flat and homorhabdic ctenidia are of Atkins's type C 2. 7. The ciliary sorting mechanisms on the ctenidia and labial palps are suited for the selection of few fine particles and for the rejection of larger quantities even of fine particles. This is considered to be well adapted to life in inshore waters that may occasionally have a very high silt content. 8. The palps are extremely efficient sorting organs and the ciliary mechanisms on the folded surfaces are comparable with those reported for other genera in the Pholadidae. 9. The ciliary cleansing mechanisms on the surfaces of the visceral mass and mantle are described. 10. There is no appendix to the stomach. In other respects the alimentary canal is closely similar in structure and function to that of other members of the Pholadidae. 11. There is an anterior median fenestra joining the cavities of the distal limbs of the left and right excretory organs as is found also in Barnea parva and Zirphaea crispata. 12. There is a transverse connective between the left and right cerebrovisceral connectives, immediately anterior to the visceral ganglia. This transverse connective is slightly swollen to form an accessory visceral ganglion, as in other genera of the Pholadidae. 13. There is an indication of slight sexual dimorphism, affecting the form both of the genital aperture and of the anal papilla. 14 pp., 7 figs, br. gr. 8. …

1. The internal structure and the ciliary sorting mechanisms of the stomach are described for representatives of twelve families of Filibranchia and Pseudolamellibranchia. 2. The variable structural features of the stomach are examined individually, and it is shown that only one of these is suitable for use as a diagnostic in assigning the stomachs of these lamellibranchs to a limited number of types. This feature is the form of the major typhlosole. 3. The major typhlosole may sweep smoothly from the orifice of the mid-gut to that of the left pouch, accompanied on its course by the ciliated rejection tract of the intestinal groove. Alternatively a long slender tongue may pass forwards from the major typhlosole and penetrate deeply into the food-sorting caecum, this tongue being accompanied by a similar extension of the intestinal groove. No intermediate condition was found, and on this basis the stomachs in eight families were assigned to Type III, in which the major typhlosole possesses such a tongue. These families are the Arcidae, Glycimeridae, Limopsidae, Pinnidae, Vulsellidae, Pteriidae, Mytilidae and Ostreidae. 4. It is considered that the evolution of a tongue of the major typhlosole, extending into the food-sorting caecum, could not have occurred independently on two or more occasions, nor is it likely that such a tongue, once having been formed, could have been lost independently on two or more occasions. It is concluded, therefore, that the above mentioned eight families constitute the end products of one phylogeny of lamellibranchs. 5. In the remaining four families, the Trigoniidae, Limidae, Pectinidae and Anomiidae, the major typhlosole lacks a tongue. The stomachs in these four families are assigned to Type IV, and attention is drawn to the fact that in many Eulamellibranch families the internal structure of the stomach is similar. 6. It is suggested that evolution of the structure and function of the interior of the stomach has played an important part in the adaptive radiation of the Lamellibranchia. 7. It is reiterated that the Protobranchia constitute a phylogeny which is distinct from all other lamellibranchia and that it is undesirable to link the Protobranchia with the Arcacea to form the order Taxodonta. 34 pp., 13 figs, br. gr. 8.…

1. The bed of the Lough Ine Rapids is covered by large laminarian seaweeds, mainly Saccorhiza bulbosa. The fronds form a dense canopy, which has a typical fauna associated with it. 2. A study has been made of the speed of the water current at the level of the canopy throughout the tidal cycle (12 1/2 hr.) at a series of selected stations. The total lengths of water-columns passing and the maximal speed of the current at each station are given in Table 1. The various stations range, in maximal speed of current, from a very low value up to 2 1/2 m./sec. 3. An investigation has been made of the distribution of animals associated with the canopy. This investigation comprises both general observations made throughout the Rapids area and a detailed study of samples of Saccorhiza collected at the stations mentioned above. Of the animals studied six species (three polyzoans and three gastropods) were confined to situations where they were exposed to weak currents only, that is, on the fronds of Saccorhiza at stations of quiet water and in some cases in the shelter of the crenulated margins (`frills') of the stipes at stations of stronger current. Two species (the polyzoan Membranipora membranacea and the limpet Patina pellucida) favoured moderate current and were less abundant in weak or strong current. Two species (the amphipod Jassa falcata and the hydroid Tubularia bellis) favoured proximity to strong current but not direct exposure to it. 4. In experiments with the gastropod Gibbula cineraria it was shown that the adult animal was washed off Saccorhiza by strong currents. 5. There are many ways in which current may directly or indirectly influence the distribution of animals in an area such as the Lough Ine Rapids. Moreover, it may act differently at different stages of the life histories of these animals. Although current is no doubt of paramount importance in the Lough Ine Rapids, the interpretation of the complex interaction of its many effects upon the animals must await much more experimental evidence and must be approached with great caution. 22 pp., 14 figs, gr. 8.…

Zustand: Acceptable. Used - Acceptable. Your purchase helps support Sri Lankan Children's Charity 'The Rainbow Centre'. Ex-library with wear and barcode page may have been removed. Our donations to The Rainbow Centre have helped provide an education and a safe haven to hundreds of children who live in appalling conditions.…

xxv, 560 p., 184 figs, cloth (dust jacket). Library stamps.

1. Form and Function of the Mantle Cavity and Associated Organs. 2. Feeding Methods and Adaptive Radiation in the Gastropoda. 3. Feeding Methods and Evolution in the Bivalvia. 4. Adaptive Radiation in the Polysyringian Bivalves. 5. Digestion. 6. Reproduction. 7. Distribution of Molluscs. 8. The Functions of the Nervous System in the Dibranchiate Cephalopoda. 560 pp., 185 figs, hardcover gr. 8.…