LEPTOMEDUSAE 37 



St. 1568. II. iv. 35. 34° 47' 36" S, 34° 27' 54" E. Net: TYFB 1400-0 m. 4 specimens. 

 St. 1587. 3. V. 35. 06° 05' N, 52° 00' E. Indian Ocean, off Somaliland. Net: TYFB 450-0 m. i specimen. 

 Stns 89, 100, 256 and 1568 are west and south-west of the Cape of Good Hope; stns 697, 698, 699 and 703 are south- 

 west of the Cape Verde Islands. 



This is a leptomedusan with a predominantly oceanic distribution, frequently found at considerable 

 distances from the coasts. It is rarely met with in the uppermost water-layers, and the records of 

 the Discovery collections indicate that it belongs mainly to the deeper parts of the epipelagic region. 

 It was collected at very different seasons, April, May, June, August and October. The diameter of 

 the specimens varies between 6 mm. and 20 mm. with no correlation with the seasons. 



Distribution. Originally described from San Diego in California (Torrey 1909) and south-west 

 of the Galapagos Islands (Bigelow 1909). Recorded from a few localities in the North Atlantic: 

 Irminger Sea (Maas 1893 as Irene viridida), south-west of Ireland (Russell 1940a and 1953) and east 

 of the Newfoundland Bank (Kramp 1948a). Also taken in several localities in the tropical East Atlantic, 

 as far south as the neighbourhood of Ascension Island (Vanhoffen 191 1 and 1912a). Some of the 

 localities where it was collected by the 'Discovery' and 'Discovery II ' are considerably farther south 

 in the Atlantic, and it has now for the first time been found in the Indian Ocean, off the east coast of 

 Africa. 



Family Aequoreidae 



Genus Aequorea 

 Besides some specimens which are too young or too mutilated to be identified with certainty, three 

 species of Aequorea were collected, and in spite of the frequently emphasized variability of these 

 medusae and the current uncertainty of the delimitation of the numerous species, I am perfectly sure of 

 the identification of these three species. Two specimens of A. coerulescens were taken off the Pacific coast 

 of South America. Of the specimens collected in various parts of the Atlantic Ocean and south-east 

 of Africa, some belong to A. aequorea and some to A. macrodactyla, two species which are not easily 

 confused when they are tolerably well preserved. None of the other Atlantic species are represented. 

 As mentioned in my paper on the medusae of the Great Barrier Expedition (Kramp 1953, p. 299), 

 I consider A. macrodactyla and A. pensilis as two distinct species, and in the present collection not 

 a single specimen has given rise to any suspicion of belonging to A. pensilis. Measurements and 

 countings were carried out in as many specimens as possible. 



Aequorea aequorea (Forskal 1775) 

 1775 Medusa aequorea Forskal. 

 1809 Aequorea forskalea Peron & Lesueur. 



1953 Aequorea forskalea Russell, p. 342. PI. 21, fig. 3; PI. 32, figs, i, 2. Text-figs. 220.\, 221. 

 Occurrence: St. 446. 9. x. 30. 36° 14' S, 16° 09' 45" E. South-west of Cape of Good Hope. Net: N 100 B 106-0 m. 



2 specimens, diam. 25 mm. and 100 mm. 

 St. 1230. 23.xii. 33. 67 miles north 62° W of Dungeness Light, Strait of Magellan. Net:BNR27m. 6 specimens, 



diam. 40-125 m. 

 St. 1889. 23. xi. 36. 45° 59' 48" S, 66° 41' 42" W. Net: N 100 B 68-0 m. i specimen, diam. no mm. 

 St. WS 2. 13. ix. 26. 22° 24' S, 13° 25' E. Off Walvis Bay, South-West Africa. Net: N 100 H 62 m. 7 specimens, 



diam. 68-85 '^'^- ^"d some fragments. 

 St. WS 95. 17. iv. 27. 48° 58' 15" S, 64° 45' W. Net: OTC 109-108 m. i specimen, diam. 62 mm. 

 St. WS 106. 24. iv. 27. 48° 25' S, 65° 00' W. Net: N 70 H 0-5 m. 3 specimens, diam. 35-100 mm. 

 St. WS749. 18. ix. 31. 52° 39' 30" S, 69° 53' 30" W. Net: NR4o(-o)m. i specimen, diam. 95 mm. 

 St. WS 770. 21. X. 31. 46° 03' S, 66° 34' W. Net: N 70 B 57-0 m. i specimen, diam. 70 mm. 

 St. WS 777. 3. xi. 31. 45° 56' S, 66° 24' W to 45° 58' S, 66° 27' W. Net: OTC 98-99 m. i specimen, diam. 80 mm. 

 With the exception of St. 446 and St. WS 2, the localities are near the coast of southern Patagonia. 



