5i 



namely Systell. cristata (Faxon), a single specimen of which was dredged in the Arabian Sea, 

 while this form was for the first time captured in the Gulf of Panama. Systell. affinis (Faxon) 

 is only known from off Grenada, one of the Antilles, Systell. echinurus Cout.. finally, only 

 from off the coast of Portugal. 



As reo-ards the variability of the vertical range the genus Systellaspis resembles the 

 o-enus Acanthephyra. While Systell. affinis Faxon, Systell. lanceocandata Bate and the variety 

 indica of Systell. debilis (A. M.-Edw.) were obtained at less than 500 fathoms, Systell. cristata 

 (Faxon) was found at 890 fathoms in the Arabian Sea, but in the Gulf of Panama even at 

 1471 and 1772 fathoms. Systell. debilis (A. M.-Edw.) has the same vertical range as Acanth. 

 purpurea and on a few occasions adults and larvae have been captured quite near the surface. 

 The depth at which Systell. echinurus Cout. occurs, has not been recorded. 



1. Systellaspis debilis (A. M.-Edw.), var. indica de Man. PI. VI, Fig. 11 — 1 1 ƒ. 



Systellaspis debilis (A. M.-Edw.), var. indica J. G. de Man, in : Zoolog. Mededeelingen, uit- 

 gegeven vanwege 's Rijks Museum van Natuurlijke Historie te Leiden. Deel II, Afl. 3 en 4, 

 1916, p. 151. 



Acanthephxra debilis A. Milne-Edwards, in: Annal. Sc. Natur. (6. Sér.), Vol. XI, 1881, p. 13. 



Acanthephyra debilis Stanley W. Kemp, Fisheries, Ireland, Sci. Invest, 1905, I., [1906], p. 16, 

 PI. II, Fig. 4—7 and 1908, I. [1910], p. 59, PI. VI, figs. 1 — 15 (Synonymy). 



Acanthephyra debilis M. J. Rathbun, in: U.S. Fish Commission Bulletin for 1903, Part III, 

 Wash. 1906, p. 922. 



Acanthephyra debilis H. Lenz and K. Strunck, Deutsche Südpolar-Expedition 1901 — 1903, 

 T. XV, Zoölogie VII, Berlin 19 14, p. 327. 



Stat. 161. August 17. i° 10'. 5 S., I30°9'E. Halmaheira Sea. 798 m. Bottom muddy sand. 

 1 egg-bearing female. 



Only one other specimen of this remarkable species which is distributed throughout the 

 Atlantic, has hitherto been observed in the Indopacific, namely a specimen which was taken 

 near Kauai Island, one of the Hawaiian Islands, at a depth of 478 to 453 fathoms (M. J. 

 Rathbün, 1. c): unfortunately no remarks about it are given, so that it remains uncertain 

 whether that specimen has shown the same discrepancies from the typical atlantic species as 

 our female from Stat. 161, which therefore is considered as a variety indica. 



The well-preserved female, obtained by the "Siboga", measures 94 mm. from apex of 

 rostrum to end of telson and in most characters agrees with the detailed and excellent descriptions 

 and figures published by Stanley Kemp. The rostrum, 24,5 mm. long, one and a half as long 

 as the carapace (15,75 mm.), is strongly curved upwards, much more than in the atlantic 

 species according to the figures in the "Recueil" of 1883 and in Stanley Kemp's papers, so 

 that the vertical distance between the apex of the rostrum and the upper margin of the 

 cephalothorax measures two-thirds the height of the latter; the upper border of the rostrum 

 appears therefore obviously concave, the lower obviously convex. The basal crest is armed with 

 4 teeth, the first three increase in size, while the 4 th is as large as the 3 rd , which is placed above 

 the orbital margin ; the rostrum proper is armed above with 9 evenly-spaced teeth of equal 

 size, that are as large as the 2 nd tooth of the basal crest. The i st of these nine teeth is almost 



