RHYSSOMATUS. 329 
4. Rhyssomatus dilaticollis, sp.n. (Tab. XVII. figg. 16, 16a, 3.) 
Oblong-oval, rather broad, moderately shining, black, the antenne and tarsi obscure ferruginous; almost 
glabrous, the legs finely pubescent. Head densely, rugulosely punctate, the eyes contiguous; rostrum 
very stout, curved, a little longer than the prothorax, closely, rugulosely punctate, feebly carinate in its 
basal half, the antenne inserted before the middle. Prothorax strongly transverse, tuberculate on each 
side inferiorly at about the middle and with the sides subparallel thence to the base, abruptly and deeply 
constricted in front ; rather coarsely, obliquely strigose and also punctate, except along a narrow smooth 
space in the centre. LElytra much wider than the prothorax, somewhat dilated at the sides inferiorly at 
about one-fourth from the base, which is sharply raised ; coarsely seriate-punctate, the punctures placed 
in shallow strie, the interstices smooth, 3, 5, 7, 9 sharply costate throughout, and 10 costate at the base. 
Mesosternum protuberant in front. Legs stout; tibia strongly sinuate within, the intermediate and 
posterior pairs sharply angulate externally and ciliate thence to the apex. 
Length 53, breadth 3 millim. (¢.) 
Hab. Mexico, Teapa in Tabasco (H. H. Smith). 
One specimen. The mesially tuberculate sides of the prothorax, the short, very stout 
rostrum, and the coarsely seriate-punctate elytra, with sharply costate alternate interstices, 
sufficiently distinguish &. dilaticollis from all others of the genus here enumerated. 
5. Rhyssomatus acutecostatus, sp.n. (Tab. XVII. figg. 17,174, 3.) 
Subrhomboidal, shining, black or nigro-piceous, the antenne and tarsi, and sometimes the elytral coste also, 
more or less ferruginous, very sparsely pubescent. Head densely, rugosely punctate, the eyes somewhat 
narrowly separated ; rostrum very stout, moderately curved, not longer than the head and prothorax, 
closely punctate, pluri-carinate in its basal half, the antennze inserted far before the middle. Prothorax 
at the base about twice as broad as long, conical, constricted in front, feebly bisinuate at the base, densely 
punctate, the punctures (especially on the anterior part of the disc and at the sides) separated by narrow, 
raised, oblique lines, the disc sharply carinate down the middle. Elytra much broader than the prothorax, 
oblongo-cordate, the obtuse, prominent humeri forming an almost continuous outline with the sides of the 
prothorax anteriorly ; seriato-foveolate, the foveze placed upon very shallow striz, the interstices 3, 5, 7,9 
from the base to the apex, 8 and 10 at the base, and the suture also, sharply costate, the other interstices 
flat and almost smooth. Beneath sparsely punctate. Legs stout; intermediate and posterior tibie 
sharply angulate externally and ciliate thence to the apex. 
Length 62-73, breadth 34-43 millim. (¢.) 
Hab. Mexico, Toxpam, Orizaba (Sallé), Teapa (H. H. Smith), Tapachula (Hoge); 
GuatEeMaLA, Las Mercedes, Cerro Zunil, and Zapote, Pacific slope (Champion). 
Ten specimens, perhaps all males. The sharply and completely costate alternate 
elytral interstices, the less approximate eyes, and the relatively shorter and stouter 
rostrum separate this species at once from #&. subcostatus. It is evidently a near ally 
of the Brazilian R. novalis (Germ.), but the general shape is probably more oblong. 
6. Rhyssomatus crenatus, sp. n. 
Subrhomboidal, shining, black, more or less mottled with rufo-piceous, the tarsi and antenne ferruginous, 
sparsely pubescent. Head densely, rugulosely punctate, the eyes contiguous; rostrum (¢ ) moderately 
stout, curved, much longer than the head and prothorax, closely punctate, pluri-carinate in its basal half, 
(¢) a little longer, almost straight, and smoother towards the apex, the antenne inserted considerably 
before the middle in the ¢, and at the middle in the 9. Prothorax much broader than long, conical, 
constricted in front, strongly bisinuate at the base, the basal margin raised; closely, obliquely strigose 
and closely, finely punctate, except along the narrow, smooth, raised, median line. Elytra much wider 
BIOL. CENTR.-AMER., Coleopt., Vol. LV. Pt. 4, January 1904. 2UU 
