PENEUS BALBOA. 181 
with light and dark color, and there are traces of color on the margins of the 
rostrum, on the dorsal carine and on the appendages. 
This species resembles S$. /evis Bate, from the region north of New 
Guinea, but may be easily distinguished from that species by the teeth 
on the margins of the abdominal pleura. Other differences are apparent on 
comparing Bate’s figure of S. devis with the figure of S. picta on Plate 
XLVI. 
PENEUS Faszr. 
Suppl. Ent. Syst., pp. 385, 408, 1798 [Pexeus']. 
Peneus balbow Fax. 
Plate XLVI, Fig. 1-1°. 
Bull. Mus. Comp. Zodl., XXIV. 211, 1893. 
Integument thin and membranaceous, its surface, when viewed through 
a lens, thickly beset with minute squamiform tubercles. The rostrum of the 
unique type specimen is broken off a little short of the anterior limit of the 
eye; on the upper margin of the part remaining, and on the median line of 
the gastric region, there is a series of eight slender, acute teeth, three of which 
lie behind the orbit; the intervals between the teeth are ciliated, and the 
lower margin of the rostrum is also furnished with long cilia. The rostrum 
is continuous posteriorly with a sharp, non-sulcated carina, which becomes 
obsolete before reaching the posterior margin; the anterior, dentate moiety 
of the dorsal carina is very thin, and sharply defined below. The antero- 
lateral border of the carapace is ciliated; the suborbital angle is prominent, 
but not armed with a spine; a small brachiostegal spine projects from the 
margin, on a level with the second antennx. Neither the cervical nor any 
other groove of the carapace is apparent. A faintly marked longitudinal 
ridge runs along the side of the carapace, on a level with the orbit; this 
carina is most conspicuous on the gastric region, becoming obsolete before 
attaining either the anterior or posterior margin of the carapace. Another 
longitudinal ridge runs from the suborbital angle, dividing into two branches 
near the middle of the carapace; the upper branch defines the upper limit 
of the branchial area, the lower branch trends diagonally, and then horizon- 
tally backward, fading out before attaining the posterior border of the carapace. 
A third ridge extends from the branchiostegal spine to the lower branch 
of the ridge last described. The fourth, fifth, and sixth abdominal segments 
