. The Cephalopoda. Cephalopoda. C. Chun mally and distally and are 3-4 mm wide in the middle. The membranes are distinctly delimited from the stem on the outer side of the club. The stem is swollen at the end into the form of a spoon or bottle and forms a fingerlike, violet glandular knob which projects beyond the tip of the club. The protective mem- branes contain thick, triangular, regularly spaced muscular supports which are contiguous at the base and extend obliquely to the stem, with their tips directed distally (Plate XL, Figure 4). These muscular supports consist of fine fibers arranged
. The Cephalopoda. Cephalopoda. C. Chun mally and distally and are 3-4 mm wide in the middle. The membranes are distinctly delimited from the stem on the outer side of the club. The stem is swollen at the end into the form of a spoon or bottle and forms a fingerlike, violet glandular knob which projects beyond the tip of the club. The protective mem- branes contain thick, triangular, regularly spaced muscular supports which are contiguous at the base and extend obliquely to the stem, with their tips directed distally (Plate XL, Figure 4). These muscular supports consist of fine fibers arranged transverse to the longitudinal direction; Joubin con- sidered them incorrectly as cartilaginous. The membranes often cover the suckers for a long distance on 247 both sides, but sometimes they are curved outward (Plate XXXVIII). These differences are obviously due to the contraction of the muscular supports, of which there are 83 on each side of the longest club. The suckers of the tentacles have long stalks and form 4 longitudinal rows. The stalks of the outer rows are longer (measuring about 3 mm) than those of the median rows. The suckers form the usual oblique rows of 4. Adjacent suckers of the outer and inner rows form pairs and alternate at their base with the muscular supports (Plate XL, Figure 4). This therefore leaves a bare space in the middle of the club which forms a zigzag stripe and is covered with chromatophores. Joubin did not show this condition distinctly enough in his diagrammatic drawing (Plate 2, Figure 6). The stalks and suckers do not bear chromatophores. The stalks are slender and usually so transparent that the nerve in them is visible. They are wider at the base and the stalks of the outer and median rows bear winglike appendages at midheight. The stalks differ in this respect from those of , in which such wings are absent according to Joubin's drawing and my observations. The dark-pigmented circular swelling which is charac- teristic for th
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Keywords: ., bookcentury1900, bookcollectionbiodivers, booksubjectcephalopoda
