. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 8 MEDUSA. I. so that there are four triangular pouches between the dorsal wall of the stomach and the subumbrella (see the textfig. 3, which is a copy of a drawing made from a specimen from the "Michael Sars" and destinated for my paper on the material of that expedition). The mouth-tube is quadrangular, very wide. The edge of the mouth is somewhat crenulated, and the corners are a little dilatated, forming four short, simple lips. The length of the manubrium is variable; it never reaches the opening of the bell ca
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 8 MEDUSA. I. so that there are four triangular pouches between the dorsal wall of the stomach and the subumbrella (see the textfig. 3, which is a copy of a drawing made from a specimen from the "Michael Sars" and destinated for my paper on the material of that expedition). The mouth-tube is quadrangular, very wide. The edge of the mouth is somewhat crenulated, and the corners are a little dilatated, forming four short, simple lips. The length of the manubrium is variable; it never reaches the opening of the bell cavity, and in most specimens its length is less than ^j^^ of the depth of the bell-cavity; this variation may depend on the state of contraction. There are four radial canals. The proximal part ('/a—^/s) of each radial canal is wide and contains the gonads, the distal part is straight and narrow and communicates with the narrow circular vessel. The proximal part of the radial canal is funnel- shaped, communicating with the stomach by a perpendicular .slit, somewhat broader at the top than at the bottom. A transverse section of the gonadial part of the radial canal is pear-shaped in the proximal part, nearly circular in the distal part. The line along which the gonadial part of the canal is attached to the subumbrella sends out a number of short lateral branches, so that the attachment of the dorsal wall of the canal has the .shape of a pinnate figure (Plate I, fig. i and textfig. 3). Occasionally this figure is somewhat irregular, or it may be more or less zig-zag-shaped. Each of the radial canals contains two rows of sack-shaped gonads, attached to the dorsal wall of the canal in the spaces between the above-mentioned lateral branches of the line of attachment and hanging down into the cavity of the canal. The surface of a gonadial sack is covered with a thin entodermal epi- Kig. 3 a,roma/o>ie„m rubrum Fewkes, seen obliquely tlielium (see Plate I, figs. c, 6, 7, and 8),
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectscienti, bookyear1919
