. The Cephalopoda. Cephalopoda. Oegopsida: Histioteuthidae 156 exactly with those of the right tentacle so that a knob of one tentacle fits into a corresponding sucker of the other tentacle. The suckers on the arms are biserial; those in the middle of the arm are large and almost spherical. In a large male of Calliteuthis ocellata, the suckers are 7 mm wide, in Histioteuthis even 8 mm wide. The smallest suckers are situated on the ventral arms; the largest suckers are 5 mm wide in Histioteuthis and only 2 mm wide in Calliteuthis. The suckers of Histioteuthis usually have short stalks and have
. The Cephalopoda. Cephalopoda. Oegopsida: Histioteuthidae 156 exactly with those of the right tentacle so that a knob of one tentacle fits into a corresponding sucker of the other tentacle. The suckers on the arms are biserial; those in the middle of the arm are large and almost spherical. In a large male of Calliteuthis ocellata, the suckers are 7 mm wide, in Histioteuthis even 8 mm wide. The smallest suckers are situated on the ventral arms; the largest suckers are 5 mm wide in Histioteuthis and only 2 mm wide in Calliteuthis. The suckers of Histioteuthis usually have short stalks and have no large teeth at the margin. Those of the club are finely toothed all around, while the suckers on the arms have only 2-4 crescent- shaped broad indentations. The suckers on the arms of Calliteuthis may have teeth or not, or they are replaced by indentations. Examination of a sucker from the opening shows that this is surrounded by a thick circular pad which is slightly wider dorsally and sometimes even covers the chitinous ring. Under the magnifying lens, the ring has a honeycomb pattern or a system of meandering lines. Median longitudinal sections of a sucker of Calliteuthis ocellata show that the short stalk is situated on a wide gelatinous cone with a central nerve which forms a small ganglion at the entrance into the sucker. The sucker consists of gelatinous tissue which forms not only the sucker itself but also the large pad. The gelatinous tissue contains radial fascicles of fibers which are connected by branches with the adjacent fascicles. In addition to these radial fibers, the circular systems of fibers appear in cross section at the posterior wall of the sucker. Such systems are also present around the opening in front of the chitinous ring. This stains intensively with various stains and shows under oblique light a radial striation which is apparently caused by prisms given off by underlying cells. The epithelium which forms the chitinous ring is cylindrical only
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Keywords: ., bookcentury1900, bookcollectionbiodivers, booksubjectcephalopoda
