PLOCAMUS.—LIMNOBARIS. 343 
Found in numbers at Chacoj in the Polochic Valley, in company with P. clavisetis, 
the specimens agreeing perfectly with others before me from the United States. 
4. Plocamus hystrix, sp.n. (Tab. XVII. figg. 29, 29 a.) 
Subelliptic, nigro-piceous or black, the base and apical margin of the elytra, the legs in part or the tarsi only, 
rostrum, and antenne, rufescent or ferruginous; the elytra each with a transverse fascia on the disc 
just beyond the middle and one or two small spots near the suture below the base, the prosternum in 
front, and the meso- and metathoracic side-pieces clothed with large, imbricate, opalescent, white scales, 
the rest of the squamiform vestiture in great part dark and inconspicuous, whitish at the apex of the 
elytra, along the middle and sides of the prothorax, and on the front of the head, that on the rostrum 
and base of the elytra ochreous, the upper surface also thickly set with very long, erect, dark sete. Eyes 
large, narrowly separated. Rostrum about as long as the elytra, arcuate, slender, gradually widened 
towards the base, finely striato-punctate, the basal portion rugulose and squamose. Prothorax trans- 
verse, evenly rounded at the sides anteriorly, strongly constricted and tubulate in front, densely punctate. 
Elytra wider than the prothorax, subtriangular, punctate-striate, the interstices densely punctulate. 
Anterior tibize strongly unguiculate. 
Length 13-17, breadth 3-3 millim. 
Hab. Guaremaa, Zapote, Pacific slope (Champion), Livingston (Barber, in U.S. Nat. 
Mus.). 
Five specimens, sex not ascertained, the one from Livingston, on the Atlantic coast, 
in beautifully fresh condition. Differs from the other species of the genus in the 
evenly rounded surface of the prothorax and in having a sharply-defined, opalescent, 
white fascia on each elytron. The vestiture is like that of P. echidna, and the rostrum 
is shaped as in P. hispidulus. 
LIMNOBARIS. 
Limnobaris, Bedel, Faune Col. Bassin Seine, vi. p. 183 (1885) ; Casey, Ann. N. York Acad. Sci. 
vi. pp. 468, 623. 
I follow Casey in including a number of oblong or oval Barids, with strongly 
decussate mandibles and completely covered pygidium *, in Limnobaris, the type of 
which is the Palearctic L. T-albwm (Linn.). Some of the American forms (such as 
L. carbonaria, Fabr.) have very long prosternal spines in the male, and one (L. latidens) 
also has the anterior femora armed with a stout blunt tooth in both sexes; others, 
again, have the anterior tibize dentate in the male (L. dentifer), or the antennal club 
greatly elongated in this sex (L. cylindriciava). L. calandriformis, latidens, aud 
quadricollis approach the “ Madarides” in having the broad flattened prosternal 
process almost on a level with the metasternum (not, however, covering the meso- 
sternum) f, but they are connected with the others by intermediate forms. Baridius 
aethiops, funereus, and wratus, Kirsch, belong to Limnobaris as here understood. The 
* In a few species with the elytra separately rounded at the apex the extreme tip is visible. 
+ The Baris complanata of Dejean’s Catalogue, alluded to by Lacordaire under the genus Lyterius (Gen. 
Col. vii. p. 251, nota), is another form of this kind. 
