. Zoology : for students and general readers . Zoology. ANATOMY OF THE BARNACLE. 993 (Fig. 327), a shell-like animal, the shell composed of several pieces, with a multivalve, conical movable lid, having an opening through which several pairs of long, many-joint- ed, hairy appendages are thrust, thus creating a current which sets in towards the mouth. The com- mon barnacle {Balaniis balanoi- des Stimpson) on every rocky shore from extreme high- water mark to deep water, and the student can, by putting a group of them in sea-water, ob- serve the opening and shutting of the valves and th
. Zoology : for students and general readers . Zoology. ANATOMY OF THE BARNACLE. 993 (Fig. 327), a shell-like animal, the shell composed of several pieces, with a multivalve, conical movable lid, having an opening through which several pairs of long, many-joint- ed, hairy appendages are thrust, thus creating a current which sets in towards the mouth. The com- mon barnacle {Balaniis balanoi- des Stimpson) on every rocky shore from extreme high- water mark to deep water, and the student can, by putting a group of them in sea-water, ob- serve the opening and shutting of the valves and the movements rig. aar.—a banmcie. Baianm n ji 1 ,,..,, porcatus. Natural size, 01 the appendages or "cirri. The structure of the barnacle may best be observed in dissecting a goose barnacle {Lepas fascicularis Ellis and Solander, Fig. 228). This barnacle consists of a body {capit- ulum) and leathery peduncle. There are six pairs of jointed feet, representing the feet of the Cyclops (Fig. 236). The mouth, with the upper lip mandibles {B, 1), and two pairs of maxillae, will be found in the middle of the shell. A short (Bsophagus (according to J. S. Kingsley, whose ac- count we are using) leads to a pouch-like stomach and tubular intestine. This form, like most barnacles, is hermaphroditic, the ovary {A, o)lying at the bottom of the shell, or in the pedunculated forms in the base of the peduncle, wliile the male gland (t) is either close to or some distance from the ovary. There is also at the base of the shell, or in the pe- duncle when developed, a cement-gland, the secretion of which is for the purpose of attaching the barnacle to some rock or weed. While the sexes are generally united in the same indi- vidual, in the genera Ibia (Fig. 229) and Scalpellum (Figs. 230, 231), besides the normal hermaphroditic form, there are females, and also males called "complementary males," which are attached parasitically both to the females and the hermaphroditic forms, livin
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectzoology, bookyear1879
