. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. pd. FIGURE 4. Setation of A, left second gnathopod; B, left first ambulatory leg; C, left first gnathopod; D, left uropod, showing placement of p, plumose setae; pd, plumodenticulate setae; and s, serrulate setae. Leg articulation There are two major flexures of the pereiopods in resting Chiridotea (Fig. 4). The first is between the coxa and basis: the basis projects ventro-medially in the gnathopods and ventro-laterally in the ambulatory legs. The second articulation is between the basis and ischium: from this articulation,
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. pd. FIGURE 4. Setation of A, left second gnathopod; B, left first ambulatory leg; C, left first gnathopod; D, left uropod, showing placement of p, plumose setae; pd, plumodenticulate setae; and s, serrulate setae. Leg articulation There are two major flexures of the pereiopods in resting Chiridotea (Fig. 4). The first is between the coxa and basis: the basis projects ventro-medially in the gnathopods and ventro-laterally in the ambulatory legs. The second articulation is between the basis and ischium: from this articulation, the leg extends as a relatively straight limb, antero-laterally in the gnathopods, almost laterally in the first ambulatories, and posterolaterally in the remaining pairs (Fig. 2). There is no ventral flexure between carpus and propodus (Fig. 4A-C). A third major flexure is found in the gnathopods; the dactyls are articulated against the propodi to form food grasping organs. The dactyls of the ambulatory legs are peg-like and ventrally directed. Setation of pereiopods Plumose setae (Fig. 6A). These are the very conspicuous (400-1000 yum) feathery setae on the posterior margins of the basis, ischium, merus, carpus, and propodus of the ambulatory legs and the basis, ischium, and merus of the second and third pairs of gnathopods (Figs. 4A, 4B). They lie within the limb plane and are perpendicular to the long axis of each segment (Fig. 6B). The setules are 50-150 yum long, and 10-30 /^m apart. They occur in two opposite rows (Fig. 6A). Plumose setae are arranged in single, evenly spaced rows, except on the basal segments where they occur in two adjacent rows. The first gnathopods may bear a few plumose setae (Fig. 4C), but often have Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Marine Biological Labor
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
