. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 82 DISCOVERY REPORTS Ampelisca macrocephala, Lilj. (Fig. 38). Walker, 1903, p. 53, pi. ix, figs. 58-61*; 1907, p. 18. Stebbing, 1914, p. 357. Occurrence: 1. St. 42. South Georgia. 2 <£<?, 8 ?$ (incl. 4 ovig.) 9-11 mm. 2. St. 123. South Georgia. Many $$, $¥. some ovig. 10-11 mm. Description. Body dorsally compressed, but scarcely keeled except slightly on head. Head moderately deep. Corneal lenses 4, upper in the / upper angle of head, lower actually on the lower margin. Postero-inferior an
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 82 DISCOVERY REPORTS Ampelisca macrocephala, Lilj. (Fig. 38). Walker, 1903, p. 53, pi. ix, figs. 58-61*; 1907, p. 18. Stebbing, 1914, p. 357. Occurrence: 1. St. 42. South Georgia. 2 <£<?, 8 ?$ (incl. 4 ovig.) 9-11 mm. 2. St. 123. South Georgia. Many $$, $¥. some ovig. 10-11 mm. Description. Body dorsally compressed, but scarcely keeled except slightly on head. Head moderately deep. Corneal lenses 4, upper in the / upper angle of head, lower actually on the lower margin. Postero-inferior angle of pleon segment 3 produced in an acute point, margin above nearly straight; pleon segment 4 with a low triangular ridge dorsally. Antenna 1 about half length of antenna 2 in $, two-thirds in <$. Antenna 2 extending to about 6th peraeon segment; 4th and 5th peduncular joints subequal. Mandibular palp with 2nd joint linear, as in the northern macrocephala. Peraeopods 1 and 2, dactyls considerably longer than 5th and 6th joints together. Peraeopod 5, 2nd joint ex- panded into a nearly evenly rounded lobe, somewhat truncate below, extending to middle of 4th joint, 3rd-6th Fig. 38. Ampelisca macrocephala, joints gradually increasing in length, 6th abruptly Lilj. «. Head. 6. Pleon segments 3 . j 1 1 ,, ,.1 and 4. c. Peraeopod z (setae on 2nd narrower than cth, narrow ovate, dactyl shorter than 6th. . "* . ,. r ~ joint omitted). Uropod 3 with rami narrow lanceolate. Remarks. This form is extraordinarily close to the northern macrocephala, Lilj., and latipes, Steph., but differs in the almost straight hind margin of pleon segment 3 above the produced point, straighter even than in latipes. Gnathopods 1 and 2 are rather stouter than in Sars' figure of macrocephala (pi. Ix, fig. 1), but gnathopod 1 is not as stout as in latipes. Peraeopod 5 is like that of latipes. On the whole this form resembles latipes more than macrocephala. In my opinion this form should be specifica
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