beous scales. Head and rostrum as in geminatus, scales unicolorous. Thorax more than a-half broader than long, apex slightly narrower, sides strongly arcuate, disc coarsely but sparsely punctured surface with plumbeous scales, a darker vitta at the sides. Elytra broadly oval moderately inflated, finely striate, striæ indistinctly punctured, intervals equal, flat, surface densely covered with cinereous or plumbeous scales. Body beneath as above. Length .24-.36 inch; 6-9 mm. Cotyloid cavities of hind tibiæ moderately cavernous, tip of tibiæ with narrow oval scaly space. This species is of more robust facies than any other of the genus and may be known by the characters given in the table. Not rare in Owen's Valley, California. Group II. Rhigopses. Rostrum quadrangular, broader in front, deeply sulcate above. Eyes narrow, acute beneath. Tarsi not dilated, beneath spinulose, third joint emarginate but not broader than the second. Corbels of hind tibiæ feebly cavernous. Posterior coxæ very widely distant. Intercoxal process broad, truncate, second abdominal segment much longer than the two following united, separated from the first by a strongly arcuate suture. Metasternal side pieces connate with the metasternum without evidence of Seventh joint of the funicle of the antennæ very close to the sutures. club. The form and vestiture of the tarsi separate this group from the Strangaliodes and the structure of the abdomen from the Ophryastes. The rostrum and the scrobes are not unlike those of Ophryastes. One genus occurs in our fauna. RHIGOPSIS Lec. Rhigopsis Lec. American Naturalist, 1874, p. 459. Rostrum quadrangular, slightly longer than the head, dilated at tip and obliquely truncate above, upper surface deeply trisulcate, tip feebly emarginate. Mentum slightly retracted. Scrobes deep, well-defined, slightly arcuate in front, directed toward the lower border of the eye. Eyes narrow, acute beneath. Antennæ moderate, scaly, scape gradually stouter attaining the margin of the eye; funicle 7-jointed, first two joints longer, stouter and nearly equal, 3-7 short, gradually broader, club oval, indis tinctly articulated. Ocular lobes prominent. Scutellum indistinct. Elytra oval, feebly conjointly emarginate, humeri prominent, tuberculate. Metasternal side pieces connate with the body without suture. Hind coxæ very widely distant, intercoxal process broad, truncate. Second segment of abdomen longer than the two following united, separated from the first by a strongly arcuate suture. Tibiæ not mucronate at tip, corbels of hind tibiæ feebly cavernous. Tarsi spinous beneath third joint feebly emarginate, not wider than the preceding. Claws moderate, free. Body densely covered with scales, almost entirely obscured by exudation coating. The tarsi of this genus although narrow are by no means of the Byrsopide type and this character appears to be of minor importance in classification in the present tribe, as two other genera already mentioned have the third joint feebly emarginate and not wider than the third. Rh. effracta Lec. Amer. Nat., 1874, p. 459. Form oval, color piceous densely covered with cupreous scales almost entirely obscured by a dark brown exudation. Head and rostrum as long as the thorax. Rostrum above trisulcate, tip obliquely truncate, front slightly concave and with a hood-like tubercle over each eye. Thorax broader than long, sides at anterior third more rapidly narrowing, posterior two-thirds feebly converging to the base, surface tuberculate and very irregular. Elytra oval, disc slightly flattened, humeri slightly oblique and with moderately large tubercle, from which a ridge or costa arises forming the lateral margin; disc bicostate, the outer terminating in a tubercle at the sides of the declivity, intervals with large foveæ separated by smaller ridges uniting the costæ; tip of elytra with smaller tubercle on each side. Body beneath scaly obscured with exudation and with short scale-like hairs. Legs dark brown, sparsely scaly and with fine scale-like hairs. Length .20-.26; 5–6.5 mm. The appearance of this insect is that of a miniature Rhigus, or of some Leptops. Its affinities appear to be rather with Ophryastes than with any other genus. Occurs in California feeding on the Yucca. The group as made up in the following table is not precisely that intended by Lacordaire. There are without doubt several genera which should be placed in his Eremnides, but with the exception of Phyxelis I can find no genus presenting such marked differences in the form of the scrobes as to render it possible to draw the line with any degree of accuracy between those genera in which the scrobes are strictly lateral and those with the scrobes arcuate and directed inferiorly. The arrangement of the genera in the following table exhibits a gradual transition in the form and length of the rostrum, from Dichoxenus which approaches most nearly Ophryastes in this respect as well as in the structure of the scrobes and abdomen, to Phymatinus with a long rostrum almost entirely lateral scrobes and normal abdomen. Cimbocera by its narrower tarsi and the structure of the antennæ approaches Ophryastes in another direction. Melamomphus resembles almost precisely Amomphus in form. I have not been able to obtain any characters from the form of the corbels of the hind tibiæ, but have been compelled to group seven genera by a character almost as feeble, the presence or absence of mucro at the tip of the hind tibiæ. Our genera exhibit such a similarity of structure that it is almost impossible to define their limits and with the addition of new material generic definition will be reduced to a work of extreme difficulty. The following table is the result of a study in which it has been my endeavor to develop a serial arrangement exhibiting, First, a gradual transition in the form of the rostrum, from the more robust to the elongate. Second, the tendency of the scrobes to change from the strongly arcuate to the nearly straight and shallow form. Third, the structure of the abdomen, with the three segments nearly equal (as in Ophryastes), to those with the abdomen of normal structure. First suture of abdomen straight; second segment rarely as long as, never longer than the two following united; hind tibiæ usually mutic. Scrobes deep, well defined, at least moderately arcuate, passing inferiorly. Scrobes strongly arcuate, passing beneath at a Scrobes moderately arcuate, passing imme- Scrobes evanescent posteriorly, badly defined, Metasternal side pieces rather wide, suture DICHOXENUS. ANAMETIS. Hind tibiæ distinctly mucronate; corbels cavernous......... Hind tibiæ not mucronate; corbels open... Metasternal side pieces indistinct, suture obliterated. Hind tibiæ not mucronate; corbels open.. First suture of abdomen arcuate; second segment as long as, and frequently longer than the two following united. Seventh joint of funicle distant from the club; third joint of tarsi broader than the second, Hind tibiæ not mucronate. Scrobes strongly arcuate, moderately deep; passing rapidly beneath at a distance Support of deciduous piece of mandible Anterior tibiæ denticulate within; sur face of body scaly without hairs ; cor- Anterior tibiæ not denticulate; surface ous MELAMOMPHUS. PANSCOPUS. ORIMODEMA. MIMETES. Sur Support of deciduous piece prominent ; meri entirely obliterated....... Scrobes very feebly arcuate, evanescent pos- by a transverse impression; side pieces Seventh joint of funicle contiguous to the club, DICHOXENUS n.g. DIAMIMUS. PERITAXIA. THRICOMIGUS. AMNESIA. PHYMATINUS. NOCHELES. CIMBOCERA. Rostrum larger and slightly narrower than the head, slightly transversely impressed at base, feebly convex above, sub-quadrangular, alæ very feebly prominent, tip emarginate and with a small smooth space. Scrobes lateral deep, well defined, arcuate, passing rapidly beneath the head at a distance in front of the eyes. Antennæ moderate, sub-apical; scape gradually cla vate, scaly, scarcely passing the anterior border of the eyes; funicle 7jointed, joints 1-2 sub equal, the first stouter, 3-7 obconical gradually shorter, club elongate oval. Eyes oval, oblique. Thorax oval, broader than long, truncate at apex and base, ocular lobe broad and moderately prominent. Scutellum indistinct. Elytra oval, not wider at base than the thorax. Metasternal side pieces indistinct. Intercoxal process of abdomen broad, slightly arcuate in front. Second segment of abdomen shorter than the two following united, separated from the first by an absolutely straight suture. Anterior and middle tibiæ feebly mucronate, the former feebly denticulate within. Articular cavities (corbels) of hind tibiæ open. Tarsi normal, densely pubescent beneath. Claws moderate, free. Body scaly and with short erect setæ. This genus should probably be referred to the group Leptopsides of Lacordaire by its rather quadrangular rostrum although the lateral grooves and carina are here entirely wanting. Whether the genus be placed in the above group or with the Strangaliodides, the form of the scrobes, the short scape and the rather short second segment with straight first suture characterize it as distinct from any genus there described. D. setiger, n. sp. Oblong oval, densely covered with moderately large, imbricated, cinereous scales, discolored brownish by an exudation, and with short erect setæ. Head and rostrum slightly longer than the thorax, densely covered with cinereous discolored scales, with erect slightly clavate setæ sparsely placed. Thorax oval, broader than long, slightly narrower in front, apex and base truncate, sides moderately arcuate, disc convex, rugulose, subgranulose at the sides, surface covered as the rostrum. Elytra oval, slightly attenuate at apex, base feebly emarginate, humeri obtuse, disc moderately convex, striate, striæ rather finely punctured, intervals slightly convex, densely scaly and with a single row of short erect set on each. Body beneath less densely clothed than above, scales slightly pearly, setæ very short and recumbent. Legs moderately densely scaly and sparsely setose. Length .24 inch; 6 mm. Occurs in Texas. Belfrage 747. MELAMOMPHUS n. g. Rostrum longer and narrower than the head, cylindrical at base, slightly broader at tip with the alæ moderately prominent, tip feebly emarginate and with a narrow smooth space. Mandibles moderately prominent, supports of deciduous pieces also slightly prominent. Mentum transversely oval, sub-mentum with short peduncle. Front convex, separated from rostrum by a slight sinuation. Scrobes short, slightly arcuate, moderately deep in front, rapidly evanescent posteriorly, directed slightly beneath the eye. Antennæ sub-terminal, moderate; scape gradually thicker to tip, passing slightly the middle of the eye, setose; funicle 7-jointed, joints 1-2 longer, the first longer than the second, 3-7 transverse, short, sub-perfoliate, and verticillate with moderately long setæ; club oval, pointed. Eyes transversely oval, pointed beneath. Thorax oval, broader than long, lobes moderate and with short fimbria. Scutellum small, triangular. Elytra oval, not wider at base than the thorax, feebly emarginate at base. Metasternum short, side pieces moderately wide, separated by an arcuate suture. Intercoxal process moderate. Second abdominal segment not longer than the two following united, first suture straight. Tibiæ mucronate, the anterior feebly denticulate within, articular surfaces of hind tibiæ cavernous. Tarsi normal. Body densely scaly and hairy. M. niger, n. sp. Form oblong oval, densely covered with brownish black scales and with moderately long black hairs. Head and rostrum longer than the thorax, |