. Copepoda. Calanoida; Copepoda. 190 COPEPODA anteriorly convex line divided into an anterior and a posterior smaller part; the labrum proper is beset with a number of shorter and longer bristles, the somewhat complicated arrangement of which is most easily understood by studying fig. 8 c. The oral surface of the labrum (PI. VII fig. 8 d) shows a rather characteristic structure; the longitudinal series on each side consists anteriorly of an oblique group of fairly long and strong spines; behind this two or three groups of comparatively long and slender setae are found, followed by a more media
. Copepoda. Calanoida; Copepoda. 190 COPEPODA anteriorly convex line divided into an anterior and a posterior smaller part; the labrum proper is beset with a number of shorter and longer bristles, the somewhat complicated arrangement of which is most easily understood by studying fig. 8 c. The oral surface of the labrum (PI. VII fig. 8 d) shows a rather characteristic structure; the longitudinal series on each side consists anteriorly of an oblique group of fairly long and strong spines; behind this two or three groups of comparatively long and slender setae are found, followed by a more medially placed, almost square, area of short spines; behind the last mentioned group, which is only separated from the corresponding one of the other side by a narrow smooth area, an oblique one covered with delicate hairs is found. The lamina labialis seems to be represented by a very short transverse plate; in front of it and the serrula 6-dentata a medial short row of fairly long setae and a longer curved lateral one of shorter setae are found. Behind the lamina labialis and between the serrulae is found on each side a short group of strong spines, almost fused with the corresponding one of the other side, as well as a more posterior and lateral group. The arrangement of the delicate hairs behind, as well as upon, the labial lobes consists, as in X ovatus (fig. 14 b) of a median and, on each side, a lateral group, in addition to more laterally placed scattered setae. fo*. Size of specimen from Thor St. 214 was 474 mm.; anterior divi- sion 3-14 mm.; urosome i-6 mm. Sars' specimens measured 4-5 mm. The fifth thoracic somite is well marked out, and its lateral corner is rounded. The comparative length of the abdominal somites and the furcal rami is 15, 83, 47, 52, 10 and 20. The antennulae extend somewhat beyond the end of the thorax, and are distinctly attenuated towards the end; they are proximally to segment 14 slightly curved, and the proximal portion forms an obtuse angle with
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Keywords: ., bookauthorhansenhj, bookcentury1900, bookdecade1910, bookyear1915
