SYSTEMATIC ACCOUNT 151 



Remarks. The Discovery collections contain four specimens of this species, three males and one 

 female; the largest of the males measures 13 mm. in length and 4-5 mm. in greatest breadth; the 

 female, which is in the breeding condition, measures 13-5 mm. in length and 6 mm. in greatest 

 breadth. The female is broader in proportion than the male, the length : breadth ratio of the former 

 being 2-25 : i , that of the latter 2-8 : i . 



There is little to add to the already existing descriptions and figures of this species; Stephensen 

 (1915, p. 13) figured a character also noted in the males of the Discovery collections, namely, the 

 presence of a thick coating of long delicate setae on the inner edge of the 2-5 joints of the second 

 pereiopod; this sexual difference does not appear in other descriptions of the species. 



CoUinge (1917, p. 747) suggested that Stephensen's figure of/, metallica is really of a new and allied 

 species, presumably because of the narrowness of the body (length:breadth ratio, 3-17:1). I fail to agree 

 with this suggestion because this is the only character in which Stephensen's/. metallica differs from those 

 in the Discovery collections, and Miers ( 1 88 1 , p. 37) had already pointed out that there was ' considerable 

 variation in the degree of prominence of the epimera and in the width of the thoracic segments. In 

 some adult examples the epimera do not project at all, and the serrated appearance of the sides of the 

 thorax is lost. The younger individuals are generally narrower, with the sides more nearly parallel.' 



Stephensen (p. 12, fig. 4) did not show the dense fringe of delicate setae which is present on all the 

 peduncular joints of the antennae as well as on the joints of the flagellum, and on the peduncle of the 

 antennule; these setae are exceptionally long in the specimen collected at St. 673. 



Distribution. This species is apparently cosmopolitan and so far has been recorded from surface 

 waters only. The Discovery specimens were collected some distance ofT the west coast of Africa. 



Genus Paridotea Stebbing, 1900 

 Paridotea ungulata (Pallas), 1772 (Text-fig. ^a-e) 



Oniscus iingulatus Pallas, 1772, p. 62. 



Idotea ungulata Lamarck, 18 18, p. 160. 



/. edwardsii Guerin-Meneville, 1843, p. 33. 



/. lalandii Milne-Edwards, 1840, p. 132. 



/. affinis Milne-Edwards, 1840, p. 133. 



7. lalandii Krauss, 1843, p. 61. 



/. affinis Krauss, 1843, p. 61. 



/. nitida Heller, 1861, p. 497. 



/. affinis Heller, 1868, p. 130; Miers, 1876a, p. 93; Thomson, 1879, p. 232. 



/. ungulata Miers, 1881, p. 52. 



Paridotea ungulata Stebbing, 1900, pp. 53-5; Chilton, 1909, p. 660; Stebbing, 1902, p. 50; Barnard, 19146, 



pp. 425-6; Nierstrasz, 1917, pp. 1 13-14, pi. xiv, figs. 43-48; Vanhoffen, 1914, p. 527; Collinge, 1918, pp. 81-2, 



pi. 8, figs. 24, 25. 

 Occurrence. St. 5: Tristan da Cunha, Quest Bay, 31. i. 26, 7-12 m., several short hauls inside Macrocystis belt, 

 2 specimens. Crawling on a female Blue Whale, Saldanha Bay; i immature specimen. 33"oi'S., 17° 58' E., 

 5. X. 26, found crawling on shark line; Houtjes Point, 8 m.-o, i <^ and i ? (breeding); Houtjes Point, 25. v. 30, 

 at anchor, depth 12 m., i ? (breeding); Capetown Docks, i. x. 30, on ship's side, i <S- St. WS. 123: 9. vi. 27, shore 

 collection, Gough Island, under stones in rock pools, 3 immature specimens. 



Remarks. The largest male in this material measures 59 mm. in length and 15 mm. in greatest 

 breadth and was collected in Capetown Docks, from the ship's side; the largest female measures 

 38 mm. in length and 10-5 mm. in greatest breadth; this specimen is in the breeding phase. 



There is little to add to the existing descriptions of this species, though it should be pointed out that 

 too much stress seems to be laid on small variations in detail. 



