FROM THE GULF OF GUINEA. 125 



Saphirina metallina, Dana. (PI. XII. fig. 4.) 



1852. Saphirina metallina, Daua, Crust. U.S. Expl. Exped. p. 1242^ pi. Ixxxvii. fig. 5. 



1860. Saphirina cylindrica, Lubbock, Trans. Linn. Soc. vol. xxiii. p. 184, pi. xxix. figs 13-15. 



1883. Saphirina metallina, Brady, Report Chall. Copep. p. 128, pi. 1. figs. 11-17. 



Rahitat. Station 2, 5, 25, and 50 fathoms, January 1st (night collections). Station 3, 

 100 fathoms, January 2ncl (day collection). Lat. 1" 55' 5" N., long. 5' 55' 5" E., 30, 00, and 

 360 fathoms, January 22nd (day collections). Station 23, surface, one day and one night 

 collection ; also in one at 20, 85, 135, and 235 fathoms, February 5tli, &c. (day collections). 



Saphirina metallina occurred in 29 tow-nettings ; only 4 of these were surface, the 

 other 25 being under-surface and ranging in de[)th from 5 to 360 fathoms. The surface 

 gatherings comjirised 1 da}- and 3 night collections, and the under-surface 19 day and 6 

 night collections, as shown by the annexed formida : — 



J 1 day collection. 



rr .,• on/ ^^^^"^'^^^ 1 3 night collections. 



Tow-nettmgs 29 < ^ o 



I 25 under-surface [ ^^ "^""^ ^^"«- 

 i 6 night ditto. 



The form of the caudal stylets in this species makes it readily distinguished from all 

 other Saphiriues. A peculiar appendage of the caudal stylets is, by deep staining, brought 

 prominently into view. The outline of the appendage may be perceived without staining 

 by observing the ditfraction of light around its edges, but it is only by allowing the speci- 

 men to be well soaked in the stain (Kleinenberg's hsematoxylin does very well to stain 

 with) that the appendage can be seen to advantage. It is then observed to possess a 

 narrow oval outline with an acute apex ; a thickened part extends from base to apex 

 like the midrib of a leaf. The whole appendage has thus the appearance of a seta 

 possessing delicate wing-like expansions. Such a leaf -like aj)pendage {cerGophyllnm) 

 has not been noticed in any other species of Saphiri)ia in the 'Buccaneer' collections. 

 These cercophylla probably enable the animal to move with greater rapidity through the 

 water, and thus to be more successful in the struggle for existence. By possessing greater 

 celerity in its movements it would be able to escape more readily from its enemies and 

 be more certain of success in attacking its prey. Whether the cercophylla are used as 

 an additional motive-power or not is at present conjectural, but the study of the animal 

 in the living state should tend to throw some light on the use of these curious organs. 



Saphiiiina sinuicalda, Brady. 



1883. Saphirina sinuicauda, Brady, Report Chall. Copep. p. 129, pi. xlix. figs. 7-10. 



Rahitat. Lat. 23 4 9" N., long. 5° 22' 2" E., 20 fathoms, January 21st (night collection)'. 

 Station 21., surface, February 6th (day collection). 



This was one of the rarest of the Saphiriues observed in the ' Buccaneer ' collections, 

 and is distinguished from the other species by the form of the inner branch of the second 

 swimming-foot and of the caudal lamellse. Only two or three specimens in all were 

 obtained. 



