162 EXPEDITION OF THE "ALBATROSS," 1899-1900. 



where in the tropical Pacific wherever the Diphyes generation is found. 

 This species may be Eudoxia Lessoni of Eschscholtz, figured by him in 

 Syst. d. Acal., p. 126, Taf. XII., Fig. 2, and by Huxley in 1859 under the 

 same name in Oceanic Hydrozoa, p. 57, PI. III., Fig. 6. 



DIPHYOPSIS ANGUSTATA. 

 ERS^EA ANGUSTATA. 



Diphyopsis angustata Haeckel. 



Diphyes angustata Eschscholtz, F., 1829; Syst. der Acal., p. 136, Taf. 12, Fig. 6. 

 Diphyopsis angustata Haeckel, 1888; Challenger Report, Zool., Vol. XXVIII., p. 152. 



Plates 8, 10, figs. 37, 1$. 



This species was first obtained by the " Albatross " in N. lat. 6° 41', 

 W. long. 137°, and from this time on throughout the cruise in the tropical 

 regions of the Pacific it continued to be the commonest of all Siphonophorae. 

 Several perfect specimens were obtained in which the posterior nectophore 

 remained attached to the siphosome. This is very readily broken off at the 

 time of capture, and it was not observed in any of the specimens obtained 

 by us in 1897 among the Fiji Islands (see Bull. Mus. Comp. Zool., Vol. XXXII., 

 p. 179, PI. 17. Fig. 54). The posterior swimming-bell is quite similar in 

 relative size and general appearance to that of D. compressa figured by 

 Haeckel, 1888; in Siphanophorae of the "Challenger" expedition, PI. 

 XXXIII., Figs. 1-4. 



We give two figures, one showing a complete unit of the siphosome a 

 short time before it is detached from the stem, and the other a drawing 

 of the terminal nematocyst battery of the tentacles. The monogastric sexual 

 generation, Ersaaa angustata, nov. sp., was met with quite frequently. 



S d , S"; Station 14; September 7, 1899; S. Lat. 6° 41', W". Long. 137°. 

 (300 f— S)"; Station 25; September 14, 1899; Marquesas Islands. 



S. Lat. 10° 29', W. Long. 141° 52'. 

 " 13° 37', " 145° 42'. 



off Point Venus, Tahiti, 

 off Fakarava Atoll. 



Lagoon of Makemo Island, Paumotus Islands. 

 S rf ; Station 1 73 ; November 4, " S. Lat. 18° 55', W. Long. 146° 32'. 

 S rf ; " 180 " 15, " " 17° 30', " 149° 41'. 



S>*; December 25, " Lagoon of Funafuti, Ellice Islands. 



S"; January 20,1900; Lagoon of Likieb, Marshall Islands. 



