. Text-fig. 1. Physalia physalts. A right-handed specimen, number 58, x | (Discovery St. 3255). Plan-view from above to show the septa of the crest. I, II = cormidia I and II (main zone). The textbook account of Physalia by Delage and Herouard (1901) contains statements—no autho- rity quoted—about crest-structure which need correction. First of all I have never seen any sign of an internal longitudinal septum in the crest. Secondly there is no perforated septum joining the edges of the primary and secondary septa, and partially enclosing the outer pockets of the pneumatocodon. In consequence i
. Text-fig. 1. Physalia physalts. A right-handed specimen, number 58, x | (Discovery St. 3255). Plan-view from above to show the septa of the crest. I, II = cormidia I and II (main zone). The textbook account of Physalia by Delage and Herouard (1901) contains statements—no autho- rity quoted—about crest-structure which need correction. First of all I have never seen any sign of an internal longitudinal septum in the crest. Secondly there is no perforated septum joining the edges of the primary and secondary septa, and partially enclosing the outer pockets of the pneumatocodon. In consequence it is untrue to say that the finger-like processes of the saccus form horizontal pairs, one on each side of a longitudinal septum. The authors also wrongly describe the gas-gland as strip- shaped: it is nearly circular. Their diagram of the relationship between crest-pockets and saccus, shown in their pi. 28, fig. 4, is useful. Here is a description of the crest of a specimen well preserved in an extended condition—specimen no. 58, taken by 'Discovery II' at St. 3255 on 13 June 1955 (in 410 08' N., 140 32' W.), right- handed, of floatlength 16 cm., gas-gland diameter 45 cm. and pneumatocyst-capacity about 300 The first developed set of septa, ten in number, hang down some 3 cm. in the central region. The major pockets are subdivided three times, and rudiments of a fourth series are visible at the crest- margin. The secondary septa are 2-5 cm. deep, the tertiaries 1 cm. and the fourth series 0-5 cm. A view of the float and crest from above is given in Text-fig. 1.
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
