SYSTEMATIC AND BIOLOGICAL ACCOUNT „ 3 



temperature dropped below 24 C. In the Red Sea off Port Sudan, ' Manihine ' found them associated 

 in five out of ten hauls (Text-fig. 55 D). 



H.M.S. 'Weston' took an abundance of specimens off Kamaran, Red Sea on 9 April 1936 at 

 a surface temperature of 28 C. Once more the species was associated with Diphyes chamissonis. 

 This species evidently thrives at a high temperature. 



Lensia leloupi 1 sp.n. (Text-fig. 55 C). 



Since there is a new species of Lensia with which L. subtiloides might be confused a description 

 is now given of the anterior nectophore. 



The nectophore differs from that of L. subtiloides in having a deeper hydroecium or longer mouth- 

 plates. In other respects it is very similar, though larger. After comparison with Muggiaea delsmani 

 it might be thought that Lensia leloupi was only another species of Muggiaea with still shallower 



Text-fig. 55. A, Muggiaea kochii, off Plymouth ; B, M. delsmani sp.n., Java Sea ; C, Lensia leloupi sp.n., ' Discovery' St. 277 ; 



D, Lensia subtiloides, Great Barrier Reef. A, C x 16; B X20; D x 18. 



hydroecium. But Lensia subtiloides and L. leloupi agree in (1) showing a notch on the edge of the left 

 mouth-plate ('right' if viewed from the dorsal side, apex uppermost); (2) the origin of the somatocyst 

 from a point on the hydroecial roof to the left of the highest point, and not nearly so close to the 

 nectosac as in Muggiaea spp. ; (3) the tip of the nectosac being so near to the apex of the nectophore. 

 This third character is found in M. bargmannae but not in the other three Muggiaea species. 



The type specimens of this new species Lensia leloupi were taken at ' Discovery ' Station 277 near 

 Cape Lopez in the Gulf of Guinea, and not far from the mouth of the Ogowe river. No salinities 

 are recorded from this station, but at Station 279, closer still inshore, the salinity was 33-08 % at the 

 surface, a comparatively low salinity for Siphonophores to tolerate. 



The figured holotype bears the Brit. Mus. (Nat. Hist.) Register No. 1952. 11. 19. 1. 



Lensia multicristata (Moser), 1925. 



This species was recorded by Browne from Chagos and Amirante under the name Diphyes bigelowi. 



New Indian Ocean records: specimens of Lensia multicristata have been identified from the following 

 'Discovery II' Stations in the Indian Ocean: 847 (270-196 m.); 1743 (2100-1150 m.); 1566 (1350- 



1 Named for Dr E. Leloup. 



D XXVII 15 



