THE MEDUSA OF THE SCOTTISH NATIONAL ANTAECTIC EXPEDITION. 235 



Family Willid^e. 



Willia mutabilis, Browne, 1902. 

 Willia mutabilis, Browne, 1902, p. 280. 



Station. — Stanley Harbour, Falkland Islands, 7th January 1903. 



A single specimen in bad condition was found in the bottle containing Desmonema. 

 This was one of the new species collected by Mr R. Vallentin in Stanley Harbour 

 during 1898-1899. 



LEPTOMEDUS.E. 



Family Laodicehle, L. Agassiz, 1862. 



Character of the Family. — Leptomedusse with cordyli, commonly called sensory 

 clubs, on the margin of the umbrella. (Browne, 1907.) 



Stauro'phora, Brandt, 1835. 



Generic Character. — Laodiceidse with four radial canals ; with a narrow cross- 

 shaped stomach, and mouth extending across the sub-umbrella ; with ocelli on the 

 basal bulbs of the tentacles. (Browne, 1907.) 



Staurophora falklandica, nova species. (Plate I. figs. 1-8.) 



Station. — Stanley Harbour, Falkland Islands, 7th January 1903. 



The collection contains a single specimen, which is in fairly good condition, but 

 rather damaged in places on the margin of the umbrella. 



Description. — The umbrella is very thin, and measures 90 mm. in diameter when 

 completely flattened out. Its natural shape would probably be something like a 

 shallow watch-glass. The velum is extremely narrow for the size of the umbrella, about 

 1 mm. in width, and is in an almost rudimentary condition. 



The stomach forms a large perradial cross, which extends nearly to the margin of 

 the umbrella, and consequently the true radial canals are very short, about 6 mm. in 

 length. The mouth is of the same length as the stomach, and has its margin arranged 

 in a complicated series of folds. The gonads (male) extend along the whole length of 

 the stomach, forming a close series of deep folds (fig. 5). This folding of the lateral 

 walls of the stomach frequently gives rise to small pockets, which are probably 

 receptacles for the digestion of food. 



The principal tentacles (fig. 4) are very numerous (several hundred), closely packed 

 together round the margin of the umbrella. Between every two tentacles there is 

 usually a very small tentacle, somewhat similar to the large tentacles in shape, but not 

 so fine and slender as a typical cirrus. 



