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fined, passing immediately beneath, and slightly beyond the lower border of the eye, not continued beneath the beak. Antennæ moderate; scape gradually clavate, slightly arcuate, passing slightly the anterior border of the eye; funicle 7 jointed, 1-2 feebly elongated, the first longer than the second, 3-7 gradually smaller; club oval. Thorax broader than long, base slightly narrower, ocular lobes very prominent. Scutellum oval or transverse. Elytra oblong, wider at base than the thorax, humeri oblique, sides parallel. Mesosternum not protuberant. Metasternum short. Intercoxal process broad, oval at tip. Second abdominal segment longer than the two following, first suture strongly arcuate. Anterior and middle tibiæ mucronate at tip, articular surface of hind tibiæ internal, not cavernous. Claws free.

Body densely scaly.

This genus may be at once distinguished from all the others of the tribe by the acute emargination of the submentum.

Two species occur in our fauna, which are distinguished as follows: Scutellum transverse, twice as wide as long. Thorax

with four discal black spaces, the two basal smaller. Black stripes of elytra regular................................ Scutellum smaller, oval. Thorax with two broad, discal, black stripes narrowly separated. stripes of elytra with irregular margins...

Black

E. pulcher Fahrs. Schönh. Gen. Curc. vi, 1, p. 310.

pulcher.

Rosenscholdi.

Form oblong, densely scaly. Head and rostrum shorter than the thorax, densely covered with cupreous scales, a round spot black. Rostrum with impressed median line, tip with feeble triangular impression. Thorax broader than long, sides strongly arcuate in front, and gradually narrowing to base, the latter slightly arcuate, disc moderately punctured, surface densely covered with cupreous scales, and with four black spots; the posterior smaller, sides of thorax cupreous, beneath the margin a black spot. Scutellum transverse. Elytra oblong, moderately convex, with rows of moderate punctures not closely placed; surface densely scaly, sutural interval cupreous; a broad, black stripe slightly narrowed at its middle, and not attaining the tip, at the side two oblong black spots, one humeral, the other sub-apical, sometimes united in an entire stripe, limb and lateral vitta cupreous. Body beneath less densely scaly, scales pale cupreous, a black spot at the side of the first two ventral segments. Legs less densely scaly, femora nearly nude at apex and base. Tibia with short, spinulose hairs within. Length .16-.32 inch; 4-8 mm.

Two varieties occur. One has the lateral black stripe entire, in the other it is broadly divided.

Occurs usually in the first variety in Florida, and in the latter in Texas. E. Rosenschoeldi Fahrs. Schönh. Gen. Curc. vi, 1, p. 309. Form oblong oval, densely scaly. Thorax as long as wide, sides in front rather suddenly convergent, posteriorly nearly parallel, disc sparsely punc tured, densely covered with cupereous scales; a broad, entire black stripe

on each side of the middle. Elytra less elongate than in pulcher, densely scaly, scales cupreous; a broad, black stripe on each side of the suture much confused at tip, lateral black stripe much more confused or even absent. Scutellum oval. Length .28 inch; 7 mm.

The above notes give the differences between this species and the preceding. It is always less elongate and more robust. Occurs in Louisiana.

Family VI. CURCULIONIDÆ.

Mentum varying in size, never concealing the base of the maxillæ, larger in the first sub-families and tribes, smaller and oval in those last placed in this memoir, ligula and palpi also varying in size.

Maxillæ exposed, palpi short, 4-jointed, rigid.

Mandibles varying according to sub-family and tribe, as mentioned below, but never with an apical scar.

Antennæ inserted at the side of the beak, varying in position, usually geniculate (only feebly so in Ithycerus, Cleonini, Piazorhinus, and Tachygonus), with the scape long, (short in Ithycerus, Piazorhinus, and Tachygonus); funiculus with from 5-7 joints; club composed of three joints and a terminal appendix, annulated, rarely articulated, and then divided into three joints; surface usually entirely sensitive, rarely (Pissodes, Lissorhoptus, Eurhoptus, Baris,) with the basal joint shining.

Head globose, eyes usually transverse, sometimes round; beak varying in form and length, labrum wanting.

Prothorax varying in form, without lateral sutures separating the prosternum; coxal cavities confluent or separate, enclosed behind.

Mesosternum variable in width, side pieces differently divided according to tribe, never attaining the coxal cavity. Metasternum variable in length, side pieces sometimes broad, sometimes narrow, indistinct only in Trachodes.

Elytra without cpipleuræ, but with an acute fold on the inner surface, limiting a deep groove in which the superior edge of the abdomen fits; pygidium sometimes covered, sometimes exposed.

Abdomen with five ventral segments, first and second closely connate ; pygidium of male divided so as to form an anal segment.

Front coxæ rounded, sometimes contiguous, sometimes distant; middle coxæ rounded, more or less separated; hind coxæ oval, not prominent, more or less distant, sometimes attaining the elytral margin, but usually entirely enclosed

Legs variable; tibiæ usually mucronate, or hooked at tip; sometimes (especially the hind pair) truncate. Tarsi usually dilated, with the third joint bilobed and spongy beneath, rarely narrow. Claws varying according to tribe, either simple or toothed, diverging and moveable, or fixed and approximate; sometimes connate, and rarely single (Brachybamus, Mononychus, Barilepton), entirely wanting in some foreign genera.

This family is by far the largest in the Rhynchophora, and therefore exhibits a greater range of variation in some of the important organs than can be seen in the other families. Certain of the most remarkable divergences from the average type may, however, be separated as sub-families, exhibiting relationships with other families, without losing the essential characters of this family; that is to say, the mandibles without scar, the tarsi with the third joint more or less dilated, not spinous beneath, the antennæ with annulated or articulated club.

Of such sub-families I recognize five in our fauna; all of very limited extent, except the Curculionida (genuini).

They may be separated as follows:

A. Condyles of mandibles on outer side, motion lateral.

Mandibles stout, feebly emarginate at tip,

with the inner edge sharp; gular peduncle broad; beak short, broad......... Mandibles without sharp inner edge; apparently emarginate at tip, with an additional cusp:

Antennæ geniculate; gular margin promi

nent, peduncle and mentum retracted. Antennæ straight, gular margin not promi

nent; claws toothed (p. 120)............ Mandibles varying in form, usually 3-toothed, sometimes oblique without teeth*, gular margin not prominent, peduncle usually long (p. 121).....

B. Condyles of mandibles on upper side, motion vertical (p. 321).........................

Sub-family I. SITONIDÆ.

SITONIDÆ.

ALOPHIDÆ.

ITHYCERID Æ.

CURCULIONIDÆ.

BALANINIDÆ.

The species of this sub-family have been heretofore classed with the Otiorhynchide group Naupacti. They differ, however, essentially by family characters; the mandibles are short, very stout, with the outer side convex, roughly punctured, and quite destitute of the apical scar which indicates the deciduous cusp; they are broadly emarginate at tip, and the inner edge is acute. These insects are easily known from other Curculionidæ by the mentum larger, more quadrate, slightly concave, and supported on a broad, but not long, gular peduncle. The maxillæ are exposed as in the lower Otiorhynchidæ, and as in all Curculionidæ, and it therefore seems singular that Lacordaire should have classed them with his Adelognathes Cyclophthalmes, without noting the exception in this respect which they make in common with Cratopus and Elytrodon. The condyle of

* In Desmoris they are also toothed on the outer edge as in Rhynchitidæ. t Lacordaire, Gen. Col. vi, 19, note.

PROC. AMER. PHILOS. SOC. xv. 96. o

the base of the mandible is visible on the outer side, the beak is short, broad, flat, and emarginate at tip. The antennal grooves extend forwards quite to the base of the mandibles; they are short and curve abruptly downwards behind the insertion of the antennæ, which are geniculate, with elongate annulated club covered with sensitive surface. The eyes are small, rounded, convex, and rather finely granulated. The front coxæ are contiguous and prominent, the hind coxæ widely separated and extend to the side margin; the tibiæ truncate at tip, without terminal hook. Tarsi dilated, spongy beneath; claws slender, simple, divergent. The ventral segments are not very unequal, and the sutures are nearly straight. The side pieces of the mesothorax are diagonally divided, and the epimera do not largely attain the prothorax; those of the metathorax are narrow, and suddenly dilated in front.

SITONES Sch.

A few species of this well-known genus occur in our fauna, and as will be observed below, several of them are also found in Europe. They may be tabulated as follows:

Setæ of elytral interspaces very obvious.

Set of elytral interspaces not, or feebly visible........

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2.

4.

3.

1. lineellus.

2. californicus.

3. sordidus. 4. vittatus.

5.

5. flavescens. 6. tibialis. 7. crinitus.

1. S. lineellus Gyll., Sch. Curc. ii, 111; Allard, Ann. Ent. Soc. Fr., 1864, 354; Curculio lin., Bons., Curc. Suec. ii, 30, f. 18, et auctorum Europ. ; S. indifferens Say, Curc. 10; ed. Lec. i, 269; S. scissifrons Say, ibid.

Kansas two specimens. I have not copied the European synonymy, which may be found in Schönherr. It varies greatly in size, the larger specimen being 7.5 mm. long.

2. S. californicus Fahr., Sch. Curc. vi, 267; Mannh., Bull. Mosc. 1843, ii, 289; S. californius (err. typ.) Allard, Ann, Ent. Soc. Fr. 1864, 370.

California and Oregon, abundant. This species also varies in size from 6.3 to 4.2 mm.

3. S. sordidus Lec., Pac. R. R. Expl. and Surveys, Entom. 54. California, San Francisco and St. Diego. Closely allied to the preceding and perhaps only a race of the same species. The form is a little less elongate, the prothorax more rounded, and the scales of a uniform dirty brown. 4. S. vittatus Lec., Pac. R. R. Expl. and Surveys, Entom.54. San Francisco, California. Also closely allied to S. californicus, but the

elytra are not tesselate, but striped, and the sides of the prothorax are more rounded, as in S. sordidus.

5. S. flavescens Allard, Ann. Ent. Soc. Fr., 1864, 346; Curc. flav. Marsham, Ent. Brit., 311; S. octopunctatus Fahr., Sch. Curc. vi, 269. cum mult. synon. Europ.; S. lepidus Gyll., Sch. Curc. ii, 104.

Atlantic States, abundant, especially near the sea shore. Quite distinct from all the preceding by the absence of erect setæ, and by the scales being narrow, hair-like and extremely small. It is abundant and widely diffused in Europe, but the American race differs from the European by the color of the scales being more rusty and less gray.

6. S. tibialis Germ., Ins. Nov. 416; Gyll., Sch. Curc. ii, 114; Allard, Ann. Ent. Soc. Fr., 1864, 350; Cure. tib. Herbst, Col. vi, 217, pl. 75, f. 5; cum synon. Europ.; Grypidius vittatus Couper, Can. Naturalist, 1865, 63. Widely diffused in Europe, where it varies greatly in size. I have received several specimens from Canada, collected by Mr. W. Couper, as types of the synonym above mentioned. It has perhaps been introduced in earth around roots of shrubs or trees; though I have one specimen from Kansas, one from Hudson Bay territory, and several from Dacota.

7. S. crinitus Gyll., Sch. Curc. ii, 124; Allard, Ann. Ent. Fr., 1864, 356; Curculio cr. Oliv., Ent. 83, 382; pl. 35, f. 550, cum mult. syn. Europe. S. seniculus Mannh., Bull. Mosc. 1843, ii, 290.

Europe, and Northern Asia; Oregon, and California. I have three specimens from Oregon, referable to this species, which is easily known by the very small size, narrow form, and absence of distinct erect setæ; the covering is squamose, grayish-white, obscurely striped on the prothorax, feebly banded on the elytra. Length 3.3 mm; 13 inch.

Sub-Family II. ALOPHIDE.

The small group of Curculionidæ, represented in Europe by Alophus, and in our fauna by several other genera, is sufficiently distinct in its oral structure to warrant its reception as a sub-family. The convex oval elytra, without humeral angles. and with the posterior part strongly deflexed, added to the more or less rounded prothorax, give an appearance not unlike certain Otiorhynchidae; and the prolongation of the antennal grooves to the tip of the rostrum, which is rather stout, increases the resemblance. There are, however, radical differences in the mandibles; which are neatly flat externally and punctured; pincer-shaped, with a sharp edge at the apex, which is more or less emarginate, and without apical scar or deciduous piece. The mentum is tolerably large, trapezoidal and flat, retracted with the gular peduncle, which is broad; the posterior edge of the latter is prominent, so that the mouth appears hollow; the maxillæ are exposed, as are also the ligula and palpi.

The beak is as long as the prothorax, rather stout, usually a little wider at tip, with distinct apical wings; the tip is feebly emarginate, and marked also in the first two genera with a deep angulated impression, from which

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