. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. LYSIANASSIDAE 53. Remarks. A casual glance at the serrate pleon segment 3 might lead one to expect that this form was Tryphosites chevreuxi, but the epistome is distinctive. The serrations on pleon segment 3 and on the 2nd joints of peraeopods 3-5 are less strong than in the latter species, the carina on pleon segment 4 is more prominent, and the telson longer. Tryphosa castellata, (Fig. 18). Occurrence: St. 222. Cape Horn. 2 ovig. $$ 11-5-12 mm. Description. Close to analogica, but easily
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. LYSIANASSIDAE 53. Remarks. A casual glance at the serrate pleon segment 3 might lead one to expect that this form was Tryphosites chevreuxi, but the epistome is distinctive. The serrations on pleon segment 3 and on the 2nd joints of peraeopods 3-5 are less strong than in the latter species, the carina on pleon segment 4 is more prominent, and the telson longer. Tryphosa castellata, (Fig. 18). Occurrence: St. 222. Cape Horn. 2 ovig. $$ 11-5-12 mm. Description. Close to analogica, but easily distinguished by the bluntly rounded antero-lateral angle of head, the more narrowly rounded and less prominent epistome, the distally widened 1st side-plate, stouter 1st gnathopod, the low rounded carina on pleon segment 4, and the less produced postero- inferior angle of pleon segment 3, with its fewer and squarer denticles. Tryphosa onconotus, Stebb. Stebbing, 1908 {Ann. S. Afr. Mm., vi), p. 65, pi. xxxv. Schellenberg, 1926, p. 276, fig. 20 (juv.); 1926 b, p. 219. Occurrence: St. 91. South Africa. 2^5 mm., 5 $$ 4—5*5 mm. (all immat.). Remarks. Schellenberg is quite right in suggesting that the acute point on the postero-inferior angle of pleon segment 3 is characteristic of the young. In half-grown specimens it still remains as a minute blunt and obscure point, but in the adult, as in Stebbing's figure, there is no trace of it. The original specimens did not come from "False Bay" as Schellenberg (1926) states, but from off the west coast of the Cape Peninsula. The species is evidently a cold-water form; its occurrence in False Bay does not dis- prove this statement, as cold currents frequently round the Cape of Good Hope and enter False Bay. It is possible that this species migrates in from the outer waters with these currents; both the present record and the ' Gauss' specimens were taken in winter (September and July respectively). The surface temperatures in T
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