184 THE SCHIZOPODA. 
GNATHOPHAUSIA WILLEMoiis-Supm (1875). 
The material is scanty, consisting of seven specimens belonging to three 
well-known species. 
2. Gnathophausia ingens (Donrn). 
1870. Lophogaster ingens Dourn, Zeitschr. wiss. Zool., 20, p. 610; taf. 31, figs. 12-14. 
1885. Gnathophausia ingens G. O. Sars, Challenger Rept., 13, p. 30, pl. 2. 
Gnathophausia calcarata G. O. Sars, Challenger Rept., 13, p. 35, pl. 4. 
1891. Gnathophausia bengalensis Woop-Mason, Ann. Mag. Nat. Hist., ser. 6, 8, p. 269. 
1906. Gnathophausia ingens ORTMANN, Proc. U.S. Nat. Mus., 31, p. 28. ¢ 
—  Gnathophausia calcarata ORTMANN, Proc. U.S. Nat. Mus., 31, p. 30, pl. 1, figs. 2a, 2b. 
Sta. 3681. Aug. 27,1899. Lat. 28° 23’ N., long. 126° 57’ W. 350 fms. to surface. 1 specimen. 
‘Remarks.— The specimen, which measures about 68 mm., agrees well with 
Ortmann’s description of G. calcarata G. O. 8S. Dr. A. Alcock kindly sent me 
Wood-Mason’s type of G. bengalensis and I can confirm Ortmann’s interpreta- 
tion that it is identical with G. calcarata. Wood-Mason said that ‘‘the upper 
lateral keels are strongly roof-shaped,”’ but Ortmann was unable to understand 
the meaning of this sentence; I suppose, however, that Wood-Mason intended 
to say that the keels in question protrude laterally as eaves above the vertical - 
sides of the carapace, when this is seen from behind or in an optie transverse 
section. 
Ortmann (1. ¢., p. 28-30 and p. 34) was of the opinion that G. ingens 
(Dohrn) G. O. Sars, is the full-grown female of G. calcarata (Will.-Suhm, M8.) G. 
O. S., and I am able to add three points corroborating his view. I examined 
Sars’s ‘‘ Challenger ” specimens of G. ingens (Dohrn) in the British Museum and 
found that it possessed the two pairs of oblique keels on the upper surface of the 
carapace, these keels being even well developed and completely similar to those 
on the type of G. calcarata; Ortmann rightly supposed that these keels had been 
overlooked by Dohrn and Sars. Furthermore Sars’s figure of the ventral epi- 
meral plates of the sixth abdominal segment in G. ingens is incorrect; the slit 
between the two posterior lobes of the plate is longer and narrower in proportion 
to the breadth of the lobes than in his fig. 6 (Pl. ID), and, what is of more 
importance, each lobe has its outer terminal angle produced into a somewhat 
short, pointed tip, while the inner terminal angle at the slit is acute but very 
slightly produced, thus situated somewhat in front of the outer tip and shaped 
about as in G. calcarata, but differing notably from Sars’s fig. 6 of G@. ingens. 
Finally Sars says in the diagnosis of G. ingens: ‘‘branchiostegal spines obsolete,” 
. but he overlooked that these spines had been broken off in his specimen. I 
think one is now justified in adopting Ortmann’s supposition and may safely 
take the step to withdraw G. calcarata, considering it only as a synonym. 
