Nemerteans, Volume 11

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Smithsonian Institution, 1910 - Bryozoa - 251 pages

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Page 39 - This large and conspicuous species is generally easily recognized by its clear, dark purplish or chocolate-brown color above, with pale margins and a trapezoidal or triangular white spot on each side of the head, and usually with a narrow white line across the neck ; and by the pinkish or flesh-colored lower surface. Ocelli in two or more rows in an elongated group on each antero-lateral margin of the head, and a pair of small sub-dorsal clusters on the transverse white nuchal band.
Page 7 - Proboscis with stylets. Mouth in front of brain, usually opening with proboscis in a single terminal or subterminal pore. Intestinal caecum present.
Page 148 - ... intestine broad, with short lateral pouches which are but little developed in posterior portion of body. Proboscis sheath without muscular walls, consisting merely of a thin membrane closely applied to the small proboscis. Proboscis but little developed, very small in size, and extremely short, without lateral pouches of reserve stylets, but armed with central stylet and basis only. Central stylet minute, usually one-third to one-half as long as basis, which is small and slender.
Page 39 - ... by its clear, dark purplish or chocolate-brown color above, with pale margins and a squarish or triangular white spot on each side of the head, and usually with a narrow white baud across the neck ; beneath, pinkish or flesh-color.
Page 53 - ... 53 10. 60 56 7i 73 Proboscis — The proboscis sheath is long and slender. Even in this elongated species it reaches within a few millimeters of the posterior end of the body. The proboscis also is slender, though of moderately large size. It reaches well backward in the body. The armature of the proboscis is especially remarkable. The central stylet is moderately slender, rather small, and rests on a moderately heavy basis. The basis is somewhat conical in form, and rounded posteriorly (pi.
Page 59 - The musculature of the proboscis consists of an inner longitudinal, and an outer circular muscular layer. Consequently there can be no muscular crosses. The cephalic glands are enormously developed. They stretch backward on all sides beyond the brain, and even reach some distance into the esophagal region. The lateral nerves lie immediately outside the circular muscular layer. There are three longitudinal blood vessels. Ocelli are usually present in great numbers, though very small. The worms are...
Page 149 - C. carcinopkila, but suspect that this may be the case. The species may be described in detail as follows: Body small, rounded, slender, of the same diameter throughout; sexually mature individuals about 4-6 mm. in length and less than half a millimeter in diameter; head not demarcated from body; lateral grooves and cerebral sense organs very inconspicuous or wanting. Color, bright orange, sometimes inclining more to reddish and sometimes to yellowish. Head a little paler, for the color is largely...
Page 148 - ... all the other layers of the body wall combined. Body musculature consists of a thin, oblique or circular muscular layer and a somewhat thicker, but yet weak, longitudinal layer internal to the former.
Page 10 - Af. alaskensif, p. 71. aaa. Caudal cirrus present in perfect specimens, but often missing. Body long and flat, with thin lateral margins. Swims readily. Dorso-ventral and diagonal muscles well developed. Eyes usually absent Cerebratulus, p. 74. 1. Very large and stout, becoming 2 meters or more in length, and 25 mm. in width. Dark, reddish brown C. herculeus, p. 75. 2. Large and ribbon-like. Slaty brown to grayish green, with thin, white, lateral margins C. marginatus, p. 75. 3. Rather short. Chestnut-brown...

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