146 STALK-EYED CRUSTACEA. 
from the latter as follows: the rostrum is straighter, its upper surface flatter 
and smoother, and its lateral teeth (especially the posterior pair) smaller. 
None of the tubercles of the gastric region are spinous. The orbital spines 
are not turned so much outward, and the spines at the antero-lateral angles 
of the carapace are shorter and more robust. There are no spines on the 
anterior portion of the fourth carina. The eyes are smaller. 
From G. ongirostris Smith, it may be distinguished by the rostrum, which 
in G. sicaria narrows from the anterior lateral teeth, and is not corroded or 
corrugated on the upper surface; its lateral teeth, moreover, are not so 
prominent. The orbital spines are smaller, less deflected outward, and they 
are separated by a wider interval from the spine at the antero-lateral angle 
of the carapace. In both species the anterior portion of the fourth carina 
is divided by a sinus into two prominences: in @. ongirostris the anterior of 
these prominences is the more salient, while in G@. sicaria the posterior one is 
the more pronounced. 
G. cecescens W.-M., another similar species, may be distinguished by the 
lanceolate outline of the rostrum and the presence of two spines on the 
anterior moiety of the fourth carina of the carapace. 
Famity GNATHOPHYLLIDA. 
GNATHOPHYLLUM Larr. 
Nouv. Dict. d’Hist. Nat., 2° éd., XXX. 72, 1819 [Gxatophyllum]. 
Gnathophyllum panamense Fax. 
Plate E. 
Bull. Mus. Comp. Zool., XXIV. 198, 1893. 
This species resembles G. elegans (Risso) of the Mediterranean Sea so 
closely that I was at first disposed to consider it identical in spite of the 
remoteness of its habitat. A close comparison, however, discloses a clear 
specific difference : in the Panama form a prominent, conical, obtuse protub- 
erance, pigmented with black, arises from the upper part of the cornea. In 
G. elegans this tubercle is wanting or reduced to the merest vestige, discern- 
ible only with a strong lens. The rostrum of G. panamense is furnished with 
seven teeth above, and one below near the tip. The intervals between the 
superior rostral teeth are furnished with long sete. In G. elegans the num- 
