334 DISCOVERY REPORTS 



hand material already several years old. Measurements of animals so strongly con- 

 tractile as jelly-fishes long preserved in formalin can never be exact. Moreover, they 

 are subject to inevitable personal error on account of the practical difficulties in taking 

 measurements of small or very large specimens. Thus I rather doubt whether, even when 

 a sufficient number of observations are regarded collectively, the most important faults 

 can be eliminated (Kramp, 1924, p. 44). Moreover, the figures in the tables hitherto 

 published are often not mutually comparable. The height of the bell, for instance has 

 been indicated by various authors in different ways, including or excluding the lappet 

 zone, the breadth measured above the central furrow or at the level of the lappets, 

 and so on. Moreover, contraction is not limited to a single organ but involves various 

 parts of the body in very difl"erent degrees (central disc, ring muscle). 



The 'Discovery' and 'Discovery IT have collected over a very wide area. The 

 material of Scyphomedusae comprises specimens from Cape Verde to the coast of the 

 Antarctic Continent. Along the whole route medusae were found both in the neighbour- 

 hood of the African coast and in the open ocean between South Africa and South 

 America. It is in these regions that the work of the ships has mainly taken place, and in 

 which the bulk of the material has consequently been collected. A short trip was made 

 from the South Orkneys to the South Shetland Islands and the Bellingshausen Sea ; but 

 it is obvious that only a few specimens have been gathered in these waters. From the 

 'William Scoresby ' there are very few catches of medusae, made between the Falkland 

 Islands, South Georgia and Coats Land. 



It will be remembered that the 'Discovery', when under the command of Captain 

 Scott (1901-3), worked in the Pacific quadrant of the Antarctic. The collections made 

 by this expedition and examined by Browne (1910) were thus caught in localities far 

 distant from those obtained by the same vessel in 1925-7 and recorded in this 

 paper. 



Scyphomedusae have been collected by several recent expeditions in the South 

 Atlantic. 



The Challenger Expedition (Haeckel, 1882) brought home: 



Two Charybdea murrayatia, Haeckel. St. 348, West coast of Africa, not far from Sierra Leone, 

 30° 10' N, 14° 51' W. Depth 200 fathoms. 



Two Atolla wyvillei, Haeckel. St. 318, South Atlantic Ocean, St Mathias Bay, not far from the 

 coast of Patagonia, 42° 32' S, 56° 27' W. Depth 2040 fathoms. 



Two Naiiphanta challengeri, Haeckel. St. 335, South Atlantic Ocean, not far from Tristan 

 d'Acunha, 32° 24' S, 13° 5' W. Depth 1425 fathoms. 



The Deutsche Tiefsee (Valdivia) Expedition (Vanhoeffen, 1903) collected only 

 along the West African coast and in the waters from the Cape to Bouvet Island. The 

 depths of the hauls are not indicated. 



Eleven AtoUa hairdi, Fewkes. In different localities in the tropical Guinea stream. 

 Four Atolla verrilli, Fewkes. In West African waters north of the Equator and between the mouth 

 of the Congo and the Cape. 



Two Atolla chtini, Vanhoeffen. Between the Cape and Bouvet Island. 

 One Atolla wyvillei, Haeckel. South-east of Bouvet Island. 



