from the Falkland Islands. 273 



bclonp;s to tlie family Bongainvillidas. This merlusa was 

 also taken by the ' Challonnror.' Tlie descriptions and figures 

 are lased upon an intermediate stage in its life-history and 

 not uj)on the fully grown adult, of which tliere are some fine 

 specimens in this collection. 



The Desmonema, a Scyphomedusa belonging to the family 

 Cyaneid^, has only been recorded by Lesson, and his 

 description is rather vague. Mr. Vallentin found a large 

 Scyj)homedusa very abundant in Stanley Harbour, but pre- 

 .«erved only one small specimen, which is, unfortunately, just 

 too young to determine for certain the genus ; it belongs to 

 the Cyaneida\ 



Stvmobracliiiim lenticnlare was taken by Mortens in 1827 

 and described by Brandt (1838). It is a Leptomedusa of the 

 family iEquorida?, which is not represented in the collection. 



Our knowledge of the Falkland Medusfe is now extended 

 to sixteen genera and seventeen species, all, with one excep- 

 tion, taken in Stanley Harbour. The harbour is described 

 in the Admiralty Pilot- Book as a large natural dock about 

 3 miles long and ^ of a mile broad, with a very narrow 

 entrance about 250 yards across. The bottom is stiff mud 

 and the deepest part is about 4-5 fathoms. 



The Hydromcdusfe {Craspedota of H?eckel) are divided 

 into four orders : — 1. Antiiomedusffi j 2. Leptomedusfe ; 

 3. Trachomedusie ; 4. Narcomcdusai. The Medusa of the 

 first two orders I regard as belonging to the littoral fauna, 

 whilst the Trachomedusse and Narcomedus^ are oceanic. 

 They only occasionally come within the littoral limits, being 

 diiven towards shore by strong winds. 



The Medusffi in this collection nearly all belong to the two 

 orders Anthomedusa3 and lieptomedusce. There are no 

 Narcomedusai and only two Trachomedusae, one of which 

 {Vaihutinia falklandica) has probably adopted a littoral liabitat 

 and lives amongst the kelp-lbrests which surround the 

 Falkland shores. The other (Aglauropsis) is a typical 

 oceanic medusa which had invaded the harbour in shoals. 



The scientific value of the collection is enhanced by its 

 being the first good littoral collection made on the shores of 

 the South Atlantic Ocean. It is the result of tow-netting 

 almost daily for three months (7th November, 1898, to 6th 

 February, 1899) in one place. ]\Iost of the Medusa? formerly 

 recorded for the South Atlantic are oceanic forms, chiefly the 

 large Scyphomedusw. There are otdy eight species of 

 Anthoraedusse and Leptomedusa previously recorded, most 

 of them from localities scattered (or not stated) along the 

 coast of Brazil. 



