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Show 170 MESSRS. L. MURBACH AND C. SHEARER ON [June 16, distance of about two-thirds the length of the bell-cavity. The proboscis is long, and the mouth a plain circular opening. The radial canals run from the tubular end of the stomach slightly upwards and then downwards to the circular canal of the bell-margin. Their course is marked by refractive granules which look like nematocysts, but which are not regularly arranged. No gonads were seen; it is probable the single example obtained was immature. Colour.-Organs pale blue. Habitat.-Victoria Harbour, collected by Shearer. Discussion.-Some doubts as to the accuracy of the above identification are raised by several of the characters, the most striking being the tentacle-bulbs. Only one individual was obtained and that had been badly preserved. II. T i A R i D M Haeckel. TURRIS Lesson. 1. TURRIS BREVICONIS, sp. nov. (Plate XVIII. figs. 1 & 2.) Specific description.-The bell is 4*5 cm. high by 3*5 cm. broad at the level of the velum. It is somewhat cubical and quite massive in appearance. The general shape of the bell corresponds with Haeckel's (18) figure of Tiara pileata (pi. 3. fig. 7). The velum is well developed and strong. On some parts of the bell-margin there appears to be but one row of tentacles ; for the greater part, however, there are two rows, arranged in a zigzag manner. The tentacles are numerous, over a hundred and forty in all. They seem quite uniform in size when mature ; the smaller ones are more irregular and evidently less developed. They are coiled and show the structure peculiar to coiled tentacles, as do those of Physalia, the ectoderm being very much enlarged on one side, while the contractile fibres of the inner side are covered with but a thin layer. There are no special tentacle-bulbs, but the tentacles spread out, clasping the bell-margin, as Haeckel (18) has described for Tiara pileata. In the preserved condition no eye-spots could be made out. The walls of the stomach are very much folded, and pushed out into pouches on either side of the radial canals, forming dependent diverticula from the angles of the stomach. There are four or five pairs of these diverticula. They bear the gonads, and are suspended to the radial canal by a double band or mesentery {cf Haeckel, 18). The proboscis is poorly developed. The four rather large mouth-lobes are periadial in position, scalloped, and finely fringed. The gonads and stomach occupy less than the upper half of the bell-cavity. The radial canals are spindle-shaped in outline, Haeckel's " lanzettformig." Throughout their length they have |