. Cephalopoda. Cephalopoda. result of the formation of new rays. If there are 12 rays already present in the stage shown in Figvire 120, it appears that these rays occupy a greater part of the mantle length than in the younger stage. We have thus to assume that a further relative increase in length takes place. 258 (259) FIGURE 122. Gladius of a young C t e n o p - teryx siculus, drawn by Merculiano for Jatta (1896). Com- pare with Plate 30, Figure 4 of his FIGURE 123. "Anlage" of the female genitalia of Ctenopteryx siculus. 6x. Compare \\rith Figures 81,82 on p. 183 and Figur
. Cephalopoda. Cephalopoda. result of the formation of new rays. If there are 12 rays already present in the stage shown in Figvire 120, it appears that these rays occupy a greater part of the mantle length than in the younger stage. We have thus to assume that a further relative increase in length takes place. 258 (259) FIGURE 122. Gladius of a young C t e n o p - teryx siculus, drawn by Merculiano for Jatta (1896). Com- pare with Plate 30, Figure 4 of his FIGURE 123. "Anlage" of the female genitalia of Ctenopteryx siculus. 6x. Compare \\rith Figures 81,82 on p. 183 and Figure 4 of Plate IV, especially the "anlage" of the ridges of the accessory nidamental glands, which are not distinct in these figures. An — anal papilla; Ed — hind intestine; Tb — ink sac; Ac — accessory gland; Np — renal pore; Mr — musculus rectus abdominis; Ni — nidamental gland; Kh — branchial heart; Od — oviduct. The dorsal corner of the mantle margin projects markedly. This is due more to a contraction of the mantle than to growth of the corner. The presence of distinct longitudinal neck folds is remarkable, but transverse neck folds are hardly visible. The first, second and third fold of P r ot ot euth i s (Figure 53 on p. 136) can be recognized; the fourth fold is absent, because of the absence of a distinct funnel pit. The third fold was already present in the preceding stage (Figure 120c) and bears the ol- factory tubercle in its posterior part; it projects markedly and appears almost stalked. Unfortunately, these places are not quite intact in the preparation. The funnel is quite typical. It is shorter than in the younger stages and has a simple attachment (cf. Plate III, Figure 4). On the other hand, the eyes have become relatively larger, not only absolutely, and the lenses are very large. This is not surprising since this is a true deep-sea form. The lid fold is slack, so that the lid is wide open and there is a small sinus at its anterior
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Keywords: ., bookcentury1900, bookcollectionbiodivers, booksubjectcephalopoda
