Image d'archive à partir de la page 700 de la cyclopaedia de l'anatomie et. La cyclopaedia de l'anatomie et physiologie cyclopdiaofana01todd Année : 1836 CIRRIIOPODA. 685 les cinq auxiliaires juste décrit, il y a huit autres petites plaques calcaires disposés autour de la jonction du pédoncule avec les coquilles. Les coquilles de l'Balanids présente plusieurs particularités de structure, et, dans leur mode de croissance, offre de le physiologue un sujet intéressant pour l'enquête. Ils forment des cônes tronqués, les bases de ce qui, sans l'intervention de pédoncules, sont fixées à des rochers, bois flottants, int

• Contributeur: Actep Burstov / Alamy Banque D'Images
• ID de l’image: W1WCJ2
• Taille du fichier: 5,7 MB (225,2 KB Téléchargement compressé)
• Autorisations: Modèle - non | Propriété - non
• Dimensions: 1323 x 1511 px | 22,4 x 25,6 cm | 8,8 x 10,1 inches | 150dpi

Informations supplémentaires

Cette image appartient au domaine public, ce qui signifie que le droit d’auteur a expiré ou que le titulaire du droit d’auteur a renoncé à ses droits. Les frais facturés par Alamy couvrent l’accès à la copie haute résolution de l’image.

Cette image peut avoir des imperfections car il s’agit d’une image historique ou de reportage.

Archive image from page 700 of The cyclopædia of anatomy and. The cyclopædia of anatomy and physiology cyclopdiaofana01todd Year: 1836 CIRRIIOPODA. 685 the five valves just described, there are other eight smaller calcareous plates arranged around the junction of the peduncle with the shells. The shells of the Balanids present several striking peculiarities of structure, and, in their mode of growth, offer to the physiologist an interesting subject for investigation. They form truncated cones, the bases of which, without the intervention of peduncles, are fixed to rocks, floating wood, integuments of marine animals, &c. These cones are composed of several pieces, closely cemented together so as to admit of no motion between them, excepting during the process of enlargement of the shell. In the common acorn-shells (jig. 333), which cover our litto- Fig. 333. ral rocks and the bottoms of ships, there are seven of these pieces, six form- ing the walls, and one dis- coid, forming the base. The outer surface of the parietal valves is mark- ed by the lines of growth in such a manner as to give it the appearance of being com- posed of twelve pieces. These may be termed compartments. They are all conical. Six of them have their bases applied to the common base of the shell, and the other six are inserted between these, with their apices towards the common base. The first six we shall refer to under the name of the first series of compart- ments («, a, jig. 333) ; the other six constitute the second series (b, b, jig. 333). The opening in the summit of the cone is closed by an opercule composed of four shelly pieces so arranged as to leave a longitudinal fissure be- tween them, through which the arms are pro- truded (c, jig. 333). The two series of com- partments differ much from one another in their external aspect, owing to the differences in the directions and appearances of the lines of growth. The second series have a smoother surface, and are marked with very de

Recherche dans la banque de photos par tags

• archive
• bookauthor
• bookdecade
• bookpublisher
• larousse 1830
• librury
• livreur de livres
• mblwhoi_library
• todd_robert_bentley_1809_1860
• zimmermann_a_albrecht_b_1860