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NEW NORTH AMERICAN PSELAPHID#. 455

DN SOME NEW NORTH AMERICAN PSELAPHIDZ,

(With Plate XVI.)
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IRV VMS, big CASEY.

Read July 18th, 1887.

The Pselaphide fauna of the Pacific coast is by no means
so insignificant as it has hitherto been considered, and as
the search for these singular and fascinating forms becomes
more specialized, and their habits and localities better
known, new species are discovered in abundance.

For those who would prosecute a more extended collec-
tion of these insects, it may be stated that the Californian
Pselaphide are very seldom found with ants, although a few
myrmecophilous species are known, but generally in fun-
gous earth, about the roots of trees, under bark, or in the
long wet moss covering the rocks in the secluded ravines of
mountainous regions. The genus Oropus, and several spe-
cies of Reichenbachia and Batrisus are peculiar to the last-
named localities, while Euplectus and Pytna are always
found under bark. Sonoma and Actium are sometimes
found under bark, but often also in fungous earth. Batri-
sus zephyrinus, on the other hand, I found in abundance at
Lake Tahoe, living in the most indiscriminate localities—
under bark, under chips buried in grassy turf, and in
fungous earth.

The following forms, most of which were collected by
myself, and which have been accumulating in my cabinet
during the past two years, are here described as new, al-
though it is possible that Actiwm californicum Lec., may be
redescribed under that genus. This can only be the case,
however, under the supposition that the description given
by LeConte for that species is erroneous in regard to the

32—BuLL. Cau. AcAD. Sci. II. 8. Issued August 2, 1887. «

456 CALIFORNIA ACADEMY OF SCIENCES.

length of the elytral striz, and as the species of this genus
are numerous and rather local, the probabilities are de-
cidedly against the formation of a synonym.

-Biotus formicarius n. gen. Tychus bipuncticeps.
Pytna corticina n. gen. Actium pallidum.
Batrisus cephalotes. politum.
luculentus. robustulum.
foveicornis. testaceum.
punctifrons. Euplectus californicus.
Decarthron Brendeli. Rhexidius granulosus n. gen.
Bryaxis arizone. Oropus montanus.
Nisaxis cincinnata. Sonoma corticina.
maritima. cavifrons

Tychus sonome

BIOTUS n. gen. (Ctenistides.)

Clypeus simple. Body covered densely with very minute, recumbent
sete. Antenne elongate. cylindrical, outer joints not enlarged, second
joint smallest. Head with two spongiose foverx; frontal tubercle divided,
the canaliculation extending slightly along the front. Prothorax transverse,
with longer, more erect and denser pubescence, trifoveate at base, the fovez
large, spongiose, not connected. Elytra. with deeply impressed sutural and
one long discal stria. Abdomen without ridges; second visible dorsal longer
than the first. Posterior coxz separated. Trochanters normal.

The maxillary palpi are very short, robust and compact;
the second joint is somewhat slender, but short; the last
two are transverse, anchylosed, forming a circular club
which is affixed obliquely to the second joint. No basal
joint is visible, and the palpi may possibly be three-jointed.
The genus should be placed near Ceophyllus Lec. from
which it differs in the remarkably minute and singular palpi.
It may be easily identified by its non-clavate antenne with
the*second joint small.

B. formicarius 2. sp.—Rather robust, pale testaceo-ferruginous through-
out; integuments shining; pubescence dense, rather long and erect on the
head and prothorax, very short and recumbent on the elytra and abdomen;

not perceptibly punctate. Head not much depressed, slightly longer than
wide; clypeus rounded, conical; labrum very short, strongly transverse;

NEW NORTH AMERICAN PSELAPHIDA. A5T

eyes large, coarsely granulate, convex, prominent, at less than their own
length from the base; the latter broadly arcuate; occiput having, on a line
through the middle of the eyes, two large, feebly impressed, spongiose fovez,
mutually scarcely more distant than either from the eye; antennw nearly
one-half as long as the body, joints two to ten transverse, cylindrical, first
joint flattened, about as long as wide, second small, eleventh slightly longer
than the two preceding together. Prothorax distinctly wider than the head,
widest in the middle; sides rather broadly rounded, almost straight near the
apex and base; the latter transverse, abruptly arcuate in the middle third,
one-third wider than the apex and but slightly narrower than the disk; apex
broadly, very feebly emarginate; posterior angles slightly rounded; disk one-
half wider than long, moderately convex, feebly tuberculate in the middle
anteriorly; median fovea feebly impressed, elongate, elliptical, beginning at
the middle and continuing nearly to the basal margin; lateral fovez smaller,
circular, deeply impressed, at one-third the length from the base. Hlytra
at base as wide as the base of the prothorax, at apex three-fourths wider;
humeri but slightly prominent; sides evenly arcuate; together very slightly
wider than long, each with two large basal foves; sutural stria coarse, deep,
nearly straight, approaching the suture toward apex; discal coarse, deep,
slightly arcuate, continuing for about three-fourths the length. Abdomen
slightly narrower than the elytra, about equal in length to the latter; sides
nearly parallel, feebly arcuate; border strong, diminishing in width; surface
broadly convex. Legs rather long and slender, alutaceous, very densely
clothed with minute recumbent set; middle trochanters very slender; tarsi
rather short; claws small, equal. Metasternum impressed in the middle,
more strongly so posteriorly. Length 2.8mm.

California (Los Angeles 2.)

The four outer joints of the antenne are more finely and
densely pubescent and slightly paler in color, the eighth
joint two-thirds wider than long, much shorter than the
ninth or ,tenth, the latter nearly equal.

This interesting species lives in the nests of a small pale
brown ant.

PYTNA 2. gen. (Tyrides.)

The present genus has the pubescence fine and subre-
cumbent and not short, robust and recumbent as in the
Ctenistides; following the classification suggested by Reit-
ter, it should therefore be placed in the group indicated.

Antenne approximate; club gradual, three-jointed. Maxillary palpi four-
jointed; basal joint minute; second long, clavate, bent; third shorter, ob-

458 CALIFORNIA ACADEMY OF SCIENCES.

conoidal, as robust as the second; third one-half longer than the second,
fusiform, equal in thickness to the second, acuminate at apex, having a
slender terminal process. Head with three small spongiose fovez at the
apices of an equilateral triangle; eyes large, convex, rather coarsely granu-
late; clypeus angulate at the sides. Pronotum with three small basal foveze
connected by a fine impressed line. Elytra each with one sutural ana one
discal stria. Abdominal border wide, nearly flat; first visible segment with a
median basal carina; first two segments equal in length. Prosternum exca-
vated in front of the cox; legs rather long; femora slightly robust, the
anterior with a short longitudinal carina beneath and near the base; middle
tibiz strongly arcuate; tarsi long and slender, three-jointed; basal joint very
small; second and third elongate, the latter the longer; claws simple, mode-
rate in length, equal, slender; anterior trochanters with a small posterior
tuberculate tooth; intermediate with a long corneous process, projecting
posteriorly from the apex obliquely outward; middle coxe narrowly, poste-
rior rather widely separated.

The modifications of the trochanters and the inferior ca-
rina of the anterior femora are not sexual characters, but
are nearly as well developed in the female as in the male.
Pytna appears to belong in the neighborhood of Tyrus, but
differs in the structure of the palpi.

P. corticina, n. sp.—Bright rufous, abdomen piceous; integuments pol-
ished; pubescence fine, rather short, moderately dense. Head very slightly
longer than wide, nearly flat above; eyes large, at more than their own
length from the base; gene convergent, feebly arcuate to the neck, clothed
with longer, more conspicuous pubescence; fovez small, the two posterior
slightly behind the middle; antennal tubercle slightly transverse, feebly
canaliculate in the middle; antennz long and slender, distinctly more than
one-half as long as the body, basal joint subcylindrical, much longer than
wide, second slightly narrower, as long as wide, very feebly obconical, three
to six subequal, very slightly shorter and narrower than the second, nearly
as long as wide, seventh and eighth very slightly smaller, equal, ninth as
long as the two preceding together, feebly obconical, one-half longer than
wide, tenth as long as the ninth, slightly thicker, feebly obconical, eleventh
ovoidal, acuminate, one-half wider than and nearly twiceas loug as the tenth.
Prothorax widest at one-third the length from the apex; sides distinctly
convergent and nearly straight to the apex; very feebly convergent and just
visibly sinuate to the base; the latter broadly and rather strongly arcuate,
searcely perceptibly narrower than the disk, one-half wider than the apex; the
latter transversely truncate; surface convex, impunctate, except near the
base; transverse line fine, parallel to the basal margin and distant from it by
one-fifth the length; fove very small: disk slightly longer than wide, very

NEW NORTH AMERICAN PSELAPHIDA. A59

slightly wider than the head. Mytra one-third longer than the prothorax,
at apex more than twice as wide as the latter; sides strongly divergent,
strongly arcuate; humeri rounded, slightly tumid; disk much wider than
long, feebly convex, coarsely but not very densely punctate, truncate be-
hind, the edge densely fimbriate; sutural striz deep, straight, beginning
distinctly before the basal margin; discal arcuate, fine, terminating at nearly
one-third the length from the apex, broadly dilated and deeply impressed
toward base. Abdomen fully as wide but scarcely as long as the elytra;
sides parallel, strongly arcuate; border wide; surface impunctate, strongly
convex; basal carina strong. Length 2.0-2.2 mm.

California (Lake Tahoe 11).

The description is drawn from the male, the sexual modi-
fication consisting of a very feeble impression in the middle
of the abdomen near the base, and a small deep emargina-
tion at the apex of the terminal segment. The female differs
but slightly, the terminal segment of the abdomen being
broadly angulate at apex.

This species was taken rather abundantly under the bark
of various fallen conifers.

BATRISUS Aubé.

B. cephalotes u. sp.—Somewhat robust, very convex, piceous; legs and
antennz pale rufo-ferruginous throughout; pubescence long, coarse, erect,
sparse, much denser on the head behind and beneath the eyes, short on the
vertex; integuments polished.

Male—Head very large, distinctly wider than long and wider than the
prothorax; surface feebly convex; apex very broadly and evenly arcuate
throughout the width between the very widely distant antennz; sides par-
allel; eyes very small, on the sides just behind the middle, convex, promi-
nent; fovez round, moderate in size, spongiose, at one-third the length from
the base, mutually twice as distant as either from the eye; connecting chan-
nel feebly impressed, becoming obsolete anteriorly near the edge of the
frontal declivity; vertex abruptly declivous between the antenne, having in
the middle of the lower edge two very approximate teeth, each of which has
a deep setigerous puncture on the upper surface near the outer edge; later-
ally the lower edge is setigerous; vertex beneath the dentiferous edge very
deeply excavated throughout the width between the bases of the antenne;
clypeus angulate at the sides, with the edges reflexed, more strongly so at
apex which is transversely sinuate; portion before the reflexed apex in the
form of a large setigerous tubercle which is further advanced than the two
teeth of the upper surface; labrum broadly sinuate, anterior angles promi-

460 CALIFORNIA ACADEMY OF SCIENCES.

nent; antenne robust, as long as the head and prothorax together, club very
large, basal joint large, one-half longer than wide, as long as the next two
together, lower surface simple but more strongly convex than the upper,
second slightly longer and more robust than the third, joints three to eight
equal in width, ninth wider, transverse, tenth much wider than the ninth,
very slightly wider than long, subglobular, eleventh wider than the tenth,
conoidal, apices of joints six to nine slightly oblique; upper surface very
coarsely, feebly and sparsely punctate at the sides near the antenne, else-
where impunctate, not carinate. Prothoraz as long as wide, widest just be-
fore the middle, where the sides are strongly rounded and rather prominent,
being abruptly and strongly sinuate and rather strongly convergent to the
base, broadly rounded to the apex; base scarcely one-fifth wider than the
apex, three-fourths as wide as the disk; the latter trisulcate; middle sulcus
narrow, deep, obsolete at one-fifth the length from the apex; having near
the base a very deep, round, nude median fovea, and two large, spongiose,
lateral foveze, between them bispinose with a longitudinal ridge proceeding
anteriorly from each spine, also tuberculate on each lateral edge near the
base; surface near the basal margin bifoveate laterally, obsoletely and very
finely carinate in the middle. Hlytra very sparsely, rather coarsely and
feebly punctate, each trifoveate at base; discal striz short, broadly, feebly
- impressed; humeri minutely and distinctly spinose. Abdomen with two
short cusps at base. Legs rather long; femora robust; posterior tibiz with
terminal process. Length 2.0 mm.

New York 1 (Mr. Henry Ulke.)

Belongs near denticollis, from which it is easily distin-
guished by the form of the bidentate vertex, this being
declivous, with the teeth upon the lower edge in the present
species, and broadly emarginate, with the teeth porrected
and but very little below the level of the front in dentzcollis.*

B. luculentus n. sp.—Rather slender, polished, piceous; elytra slightly
paler and more rufous; legs pale; antenne dark rufous, club paler; pubes-
cence rather sparse. ;

Male— Head rather large, wider than long, wider than the prothorax, very
feebly convex, coarsely, sparsely and feebly punctate anteriorly, impunctate
posteriorly; eyes moderate, convex, prominent, near the base; foves deep, —
round, nude, at two-fifths the length from the base, mutually distinctly
more than twice as distant as either from the eye; arcuate groove fine, deeply

* Nore—From material recently sent me for identification by Dr. Emil
Brendel, I find that this species is widely diffused through the North At-
lantic districts, there being specimens in the series indicated from New York
and Illinois.

NEW NORTH AMERICAN PSELAPHIDA. A461

impressed near the fovew, becoming completely obsolete anteriorly; vertex
gradually declivous between the antenne the declivity broadly biimpressed,
the impressions setigerous; lower edge bidentate in the middle, the teeth
slightly reflexed and with many erect sete on the lower surface, deeply ex-
cavated beneath between the antenne; clypeus broadly arcuate anteriorly,
sides feebly divergent posteriorly and nearly straight, angles slightly rounded;
not prominent, surface conical, edge not at all reflexed, having in the middle
an abrupt, small, strongly elevated tubercle at a considerable distance from
the anterior margin and rising just before the two superior teeth, exceedingly
minutely and sparsely setose; labrum broadly emarginate, angles prominent;
antenne slightly longer than the head and prothovax together, moderately
robust, very strongly clavate, basal joint more convex beneath, not otherwise
modified, as long as the next two together, second longer and more robust
thin the third, eighth shortest, strongly transverse, ninth slightly longer
and nearly one-half wider than the eighth, transverse, tenth large, nearly
twice as wide as the ninth and very nearly as long as wide, sides parallel,
arcuate; eleventh distinctly narrower than the tenth, acumiaate. Prothoraa
slightly longer than wide; dorsal ridges and median sulcus almost completely
obsolete; median basal puncture small, round, nude, impressed; lateral
slightly larger, spongiose; lateral sulcations broadly impressed, feeble; lateral
basal tubercles minute; surface near the basal margin bifoveate at the sides,
not at all carinate in the middle; disk convex, widest before the middle;
sides rather broadly rounded, feebly sinuate toward base and apex; base
slightly more than three-fourths as wide as the disk, one-fourth wider than
the apex. Jlytra fully as long as wide, convex; humeri slightly prominent.
but not at all spinose. Abdomen with two long, parallel, prominent cusps at
base, distant by one-fifth the abdominal width. Zegs rather long; femora
moderately robust; middle tibiz with an internal apical spur; posterior
feebly arcuate, with a terminal process. Length 1.7 mm.

District of Columbia 2 (Mr. Henry Ulke).

The female has the vertex strongly declivous, and thence
less strongly and continuously so over the surface of the clyp-
eus, which is finely, strongly and densely granulose; the
vertex is not excavated between the bases of the antenna,
each of which is inserted in a large lateral excavation. The
antenne are more slender, with the outer joints gradually
wider, the tenth transverse and but slightly larger than the
ninth.

This species should also be placed near denticollis; these
three species belong to the nigricans group; the latter is,
however, distinguished by the unusual structure of the

462 CALIFORNIA ACADEMY OF SCIENCES

antenne, the third joint of which is, according to the de-
scription of Dr. Le Conte, presumably more robust than
the second.

B. foveicornis 0. sp.—Rather slender, convex, rufous throughout; integ-
uments polished, impunctate; pubescence rather long, coarse and sparse.

Male—Head moderate, slightly longer than wide, very slightly wider than
the prothorax; vertex between the antenne coarsely, feebly and not densely
punctate, punctures asperate, elsewhere impunctate; eyes small, very con-
vex, prominent, rather finely granulate; base behind them broadly arcuate;
surface very feebly convex, very feebly and finely carinate in the middle
near the base, finely and distinctly carinate at each side above the eyes;
arcuate groove broadly impressed, extending from the base at the sides to
the vertex, where it becomes very feeble; foveze small, nude, very deep,
perforate, situated at less than one-third the length of the superior portions
from the base, and on the inner margin of the arcuate impression; vertex
declivous and slightly produced in the middle, being separated from the
clypeus by a narrow, feebly impressed transverse groove; clypeus large,
prominent, conical, strongly rounded anteriorly, very obtusely angulated at
the sides, edges not at all reflexed; antenne rather slender, as long as the
head and prothorax together, basal joint subcylindrical, not modified, nearly
as longas the next two together, two to seven subeqnal, distinctly longer
than wide, the second slightly more robust and the sixth a very little shorter,
eighth equal in width, distinctly wider than long, ninth equal in length to
the eighth, one-third wider, inner side much more strongly convergent
toward apex, tenth abruptly very large, nearly twice as wide as the ninth,
fully as long as wide. flattened, sides parallel, almost straight, eleventh as
wide as the tenth, as long as the three preceding together, ob'iquely acumi-
nate, very slightly flattened on the lower side. Prothorax widest slightly
before the middle; sides strongly rounded, convergent and feebly sinuate
toward base and apex; median and lateral fovez almost equal, deep, at
nearly equal distances from the base, the median nude; median groove short,
feebly impressed, lateral more distinct; basal spines small; ridges distinct,
becoming obsolete before the middle, separated behind from the spines by
transversely arcuate impressions; base bifoveate at each side; disk strongly
convex, very slightly longer than wide, base much wider than the apex.
Hlytra fully as long as wide, nearly twice as wide as the prothorax, very
convex; humeri prominent, not spinose. Abdomen nearly as wide and as
long as the elytra; basal cusps rather long, strong, separated by scarcely
one-sixth the abdominal width. JZegs long, slender; anterior trochanters
minutely toothed posteriorly; posterior tibiz with an apical process; tarsi
very long and slender, the posterior one-half as long as the tibiz. Length
1.9mm.

Tennessee 2 (Mr. Henry Ulke).

NEW NORTH AMERICAN PSELAPHIDA. 463

The large flattened tenth antennal joint has, on the lower
surface and near the base, a very laryve deep circular perfo-
rate fovea. Of the species in which the tenth antennal
joint is enlarged in the males, there are some—for example
cephalotes—in which this joint, although unusually large
and prominent, is almost completely unmodified upon the
lower surface, others —virginie, denticollis, etc. — which
have the lower surface slightly flattened and with a small,
deep fovea near the base; but in no case which has come
under my observation is this fovea one-half so large, or the
joint itself so strongly flattened as in the present species.

The two specimens indicated are males. The species
probably belongs near spretus Lec., which is described as
black.

B. punctifrons n. sp.—Moderately robust, convex, piceous-black; elytra
very slightly paler, rufo-piceous; legs and antenne pale rufo-ferruginous,
the latter slightly darker toward base; integuments polished, impunctate;
pubescence rather long, sparse, flavate.

Male—Head moderate, slightly longer than wide, just visibly wider than
the prothorax; eyes moderate, convex, at their own length from the base;
gene strongly convergent, feebly arcuate; base broadly sinuate; surface
feebly convex, very finely, feebly, arcuately carinate above the eyes; im-
pressed groove continuous from the base at the sides to the vertex, at which
point it is but slightly more feeble; foveze deep, nude, in the middle of the
groove; vertex coarsely, sparsely and feebly punctate on the antennal tuber-
culations, which are large and flat, declivous anteriorly, the declivity moder-
ate, beginning along a straight line between the antenn; apex strongly
rounded; declivous surface very strongly, finely and densely punctate, each
puncture bearing a very minute, coarse, flavate seta; apex divided from the
elypeus bya fine, transverse, strongly arcuate, deeply impressed groove;
clypeus short, broadly subangulate, obtusely angulate at the sides; surface
finely scabrous, conical; edges not at all reflexed; having in the middle a
small, f-eble tubercle which bears a tuft of rather long, erect, flavate sete;
antenne rather long, slender, one-fourth longer than the head and protho-
rax togetber, club strong, basal joint not modified, cylindrical, shorter than
the next two together, second much longer and distinctly more robust than
the third, joints two to seven longer than wide, eighth equal in width, nearly
as long as wide, ninth wider and longer, tenth similar to the ninth, dis-
tinctly wider and longer, slightly wider than long, inner side much shorter
than the outer, eleventh large, twice as wide as the tenth, ovoidal, acumi-
nate, nearly as long as the four preceding together. Prothorax slightly longer

464 CALIFORNIA ACADEMY OF SCIENCES.

than wide, widest slightly before the middle; base two-thirds as wide as the
disk, one-fourth wider than the apex; median sulecation feebly impressed,
becoming obsolete at one-third the length from the apex; spines moderate;
ridges almost obsolete; lateral grooves broadly, feebly impressed; foves
large and deep. Hlytra fully as long as wide; humeri prominent, not
spinose. Abdomen nearly as wide as, but much shorter than the elytra;
basal cusps fine, strong, rather long, parallel, separated by one-fifth the ab-
dominal width. Legs long, slender; posterior tibizs with apical process.
Length 1.8 mm.

Pennsylvania 1 (Mr. Henry Ulke.)

This species is very distinct in the characters of the vertex
and antenne; the eleventh joint is here more than usually
developed, while the tenth is but slightly larger than the
ninth and of nearly the same form.

DECARTHRON Brend.

D. Brendeli 2. sp. — Form somewhat robust, convex, piceo-castaneous
throughout; legs and antennez paler, rufous; pubescence rather long and
sparse, more dense on the abdomen and at the sides of the prothorax and
head; integuments polished. Head moderate, as wide as long, very feebly
convex, almost impunctate; eyes large, coarsely granulated, convex and
prominent; genz extremely short behind them; base wide, transversely
truncate; on a line through the anterior portions of the eyes there are
two widely distant nude fovee; antennal tuberculations large, distinctly
elevated; antennez as long as the head and prothorix together, rather slen-
der, club rather large, basal joint cylindrical, slightly longer than wide,
second slightly shorter and narrower, third feebly obconical, as long as and
much narrower than the second, four to six subequal, very slightly longer
than wide, and just visibly wider than the third, seven larger, scarcely as
long as wide, eight very short, transverse, narrower than the seventh, ninth
much wider than the seventh, very feebly trapezoidal, nearly twice as wide
as long, tenth very slightly wider than the ninth, ovoidal, pointed, nearly as
long as the three preceding together. Prothorax scarcely as wide as the
head, very slightly wider than long; sides broadly rounded, convergent
and feebly sinuate toward base; the latter broadly arcuate, four-fifths as
wide as the disk, one-half wider than the apex; disk strongly, evenly con-
vex, not impressed at the sides, having a deep nude fovea in the middle near
the base. Hlytra near the apex fully twice as wide as the prothorax; sides
strongly divergent, arcuate; disk wider than long, two-thirds longer than the
prothorax, convex, coarsely and extremely feebly punctate; sutural striz
deep, feebly arcute; disc1l deeply impressed, feebly arcuate, parallel to the
suture, terminating at nearly two-fifths the length from the apex. Abdomen

NEW NORTH AMERICAN PSELAPHIDA. 465

two-thirds as long as the elytra, nearly as wide as the latter; first segment
when viewed vertically, occupying three-fourths of the entire length, feebly
conyex; border narrow, flat; basal carinz strong, very feebly divergent,
slightly more than one-half as long as the segment, separated by one-half
the entire width. JZegs rather long and slender. Length 1.3-1.5 mm.

Texas (Galveston 8).

The above described type is a male. In this sex the
middle femora are very singularly modified, being very
strongly swollen, abruptly constricted near the apex, im-
pressed anteriorly, with an anterior tooth near the apex
and just before the deep apical constriction. In the female
the femora are all simple and rather slender, and the seventh
antennal joint is smaller than the eighth. The female is,
in addition, smaller than the male, and has the -dorsal
carine of the abdomen distinctly shorter.

Ihave dedicated this very distinct species to a friend,
the author of the genus, and one to whom our systematic
knowledge of the American representatives of the family is
greatly indebted.

BRYAXIS Leach.

B. arizone n. sp.—Form rather slender, pale testaceous throughout;
shining, not distinctly punctate; pubescence very fine, short and rather
sparse. Head moderate, triangular; eyes large, prominent; occipital fovez

ona line just before the middle of the eyes, mutually more than twice as
distant as either from the eye; apical fovea equal to the occipital, slightly
less distant from either of the others than the mutual distance of the latter;
connecting channel almost obsolete; antenne slender, slightly longer than
the head and prothorax together, joints three and five each nearly twice as
long as wide, distinctly longer than the fourth and equal in length to the
second, the latter more robust, seventh distinctly shorter than the sixth,
slightly longer than wide, eighth, ninth and tenth distinctly wider than long,
increasing uniformly and very rapidly in size, eleventh wider than the tenth,
much longer than wide, obliquely acuminate. Prothorax widest at the mid-
dle; sides rounded anteriorly, rather deeply sinuate posteriorly; base broadly,
very feebly arcuate, five-sixths as wide as the disk, nearly one-half wider
than the apex; the latter very feebly arcuate; disk distinctly wider than long,
_equalin width to the head, convex; middle fovea slightly smaller than the
lateral, the former at one-fifth, the latter at nearly one-third the length from
the base. Llytra at the humeri very slightly wider than the prothorax, at
33—BULL. Cau. ACAD. Scr. II. 8, Issued August 2, 1887.

466 CALIFORNIA ACADEMY OF SCIENCES.

the apex slightly less than twice as wide as the latter; disk distinctly wider
than long, moderately convex; sutural stri# strong, nearly straight, conver-
gent and arcuate near the apex; discal fine, feebly impressed, feebly sigmoid,
becoming obsolete at one-fifth the length from the apex. Abdomen slightly
shorter and very little narrower than the elytra; sides nearly straight and
parallel; border moderate in width; surface broadly and feebly convex; first
segment, the only one seen when viewed vertically, nearly five-sixths as long
as the elytra. Legs slender. Length 1.2 mm.

Arizona (Tucson 1).

Described from the male, the sexual characters being simi-
lar in form to those of texana, but having the median tuber-
cle of the. second segment smaller, less transverse and much
more prominent.

This species belongs to the texana group of the genus,
which is distinguished by the great development of the first
ventral segment in the male, this being the only part of the
abdomen seen when viewed vertically. It differs from texana
in its smaller size, sightly more robust form, much shorter
elytra, narrower abdominal border, in the size and position
of the pronotal fovew, and in its shorter antennz with less
prominent club; the eighth, ninth and tenth joints in texana
are much less transverse. In texana the median fovea of
the pronotum is larger, and at about one-fourth the length
from the base, the three fovez being more nearly on a trans-
verse line than in arizone.

NISAXIS Casey.

N. cincinnata n. sp.—Slightly robust, clear testaceous throughout; legs
and antenne slightly paler; pubescence moderately dense, rather long. Head
very slightly narrower than the prothorax, as long as wide; eyes rather large,
prominent, at two-thirds their own length from the base; genz very feebly
convergent toward base, feebly arcuate, not at all prominent; base trans-
versely truncate; front large, quadrate, feebly convex, coarsely, deeply, not
densely punctate, impunctate in the middle, feebly biimpressed near the
vertex; antennz about as long as the head and prothorax together. first two
joints nearly equal, slightly more robust, one-half longer than wide, nearly
cylindrical, third obconical, longer than wide, much shorter than the second,
as long as the fifth, longer than the fourth, sixth and seventh slightly shorter,
very little longer than wide, eighth very slightly wider, a little wider than

NEW NORTH AMERICAN PSELAPHIDA. 467

long, shorter than the seventh, ninth two-thirds wider than the eighth, ob-
trapezoidal, outer side more oblique, tenth one-half longer and wider than
the ninth, one-half wider than long, eleventh distinctly wider than the tenth,
as long as the three preceding together, longer than wide, obliquely acumi-
minate. Prothorazx widest at two-fifths the length from the apex; sides
strongly rounded, feebly incurvate toward base; the latter broadly, evenly
arcuate, three-fourths as wide as the disk, nearly two-thirds wider than the
apex; disk one-third wider than long, evenly convex, rather coarsely, ex-
tremely feebly and not densely punctate; having in the middle, at one-fifth
the length from the base, a small nude punctiform fovea, and, at each side,
a larger feebly impressed nude fovea at one-third the length from the base.
Filyira at the humeri distinctly wider than the prothorax, together distinctly
wider than long, one-half longer than the pronotum, and, at apex four-fifths
wider than the latter; disk moderately convex, sutural stria deeply impress-
ed, evenly, feebly arcuate; discal fine, distinct, extending very slightly be-
yond the middle; sutural fovex very small and at the extreme basal margin;
lateral larger and further from the base; base otherwise devoid of fovex;
surface very minutely, feebly and sparsely punctate. Abdomen two-thirds
as long as the elytra, nearly equal in width, occupied for six-sevenths the
entire length when viewed vertically by the basal segment; border rather
narrow, flat; surface moderately convex, finely, feebly and sparsely punctate;
basal carinez divergent, straight, strong, nearly one-half as long as the seg-
ment, separated by one-half the abdominal width. Legs rather long and
slender; posterior tibizs abruptly bent near the apex, middle coxa large,
globose, not prominent, distinctly but narrowly separated by the sternal
processes which are truncate and not carinate; posterior small, widely sepa-
trated. Length 1.1 mm.

Texas (Galveston 10).

Described from the male in which the first two dorsals
are simple, the third transversely and feebly impressed, the
impression large and anteriorly lunate, the inclosed apical
elevation being feebly convex and bearing a loose tuft of
long erect sete; fourth and fifth normal, broadly arcuate
at apex, the latter short and with the posterior margin very
feebly produced in the middle. Viewed from beneath the
abdomen consists of three visible segments, although there
is probably a fourth which is completely hidden under the
third; the basal segment is very long, and, in the middle,
occupies the entire extent, except a very small apical por-
tion where the two short posterior segments become very
short, the third being at this point deflexed and channeled

468 CALIFORNIA ACADEMY OF SCIENCES.

externally. Besides the tuft of long sets from the median
elevation of the third segment, there are many long con-
spicuous sete on the second, and at the sides and base of
the third. :

N. maritima 1. sp.—Form somewhat slender, dark rufous throughout;
elytral apices slightly darker; legs and antennz very slightly paler; pubes-
cence long, rather coarse, not dense. Head slightly narrower than the
prothorax, nearly as wide as long; eyes moderate, at nearly their own length
from the base; gene feebly arcuate, not at all prominent, as long as the eye;
front feebly convex, feebly, finely and sparsely punctate toward the eyes,
impunctate in the middle; antennz slender, about as long as the head and
prothorax together, nearly as in cincinnata, ninth joint symmetrical, but
slightly wider than long, tenth strongly transverse, truncate at base and
apex, nearly cylindrical, eleventh elongate, but slightly wider than the tenth.
Prothorax one-fourth wider than long, widest before the middle; sides
strongly rounded, strongly sinuate near the basal angles; base broadly arcu-
ate, nearly four-fifths as wide as the disk, one-half wider than the apex; sur-
face very minutely, feebly and sparsely punctate; basal fovea very small, at
one-fifth the length from the base; lateral moderately deep, larger, at one-
fourth the length from the base. WHlytra slightly wider than long, at apex
four-fifths wider than the prothorax; sides feebly divergent; disk rather
strongly convex; sutural striz strong, feebly arcuate; discal fine, distinct,
extending from near the base for two-thirds the length. Abdomen but slight-
ly more than one-half as long as the elytra; border rather narrow; basal
carine short, one-fifth as long as the basal segment, divergent, feeble, sepa-
rated by slightly more than one-half the abdominal width. Legs long and
slender; posterior tibiz bent near the apex. Length 1.0 mm.

Texas (Galveston 3.) i

The description is taken from the male, the sexual char-
acters being very remarkable. The first dorsal segment oc-
cupies nearly the entire extent of the abdomen when viewed
vertically, and has the apex abruptly deflexed in the middle,
the deflexed portion being transversely impressed or exca-
vated; its lower margin is reflexed and broken into two
lateral crests and a small median and strongly elevated
tubercle; the edge of the segment immediately above the de-
flexed excavated portion is more densely setose and bears
two feeble tubercles. The second segment is short, trans-
versely and very deeply excavated in the middle third, the

NEW NORTH AMERICAN PSELAPHIDA., 469

excavation being anteriorly arcuate and extending under the
apical process of the first; at the apex there is in the mid-
dle a strongly elevated carinate tubercle which is slightly
transverse, with the apex directed anteriorly for a slight
distance over the excavation, and bearing two fine setiform
appendages; its posterior surface is feebly and minutely
tuberculate; the surface of the segment has, at each side
of the central excavation, a transverse arcuate canalicula-
tion which is disconnected. The third segment has, just
before the middle, two small tubercles distant by nearly
one-half the width, the remainder of the surface being un-
modified. Fourth segment unmodified. Fifth shorter,
feebly produced in the middle.

The under surface, as in cincinnata, consists of but three
visible segments, the first being very long, the third ab-
ruptly and narrowly deflexed in the middle, the deflexed
portion being channeled externally. There is, however, a
fourth segment to be seen by looking longitudinally under
the third, by which it is entirely covered. The surface of
this fourth segment is abruptly arched at each side between
the middle and the lateral edges, the arching being visible
as a semicircular emargination of the edge when viewed
longitudinally, and there is on the edge in the middle a
strong vertical spine which appears to fit into the
channel in the deflexed apex of the third segment.

These species belong near tomentosa Aubé, but appear to
be smaller and more sparsely pubescent. ‘The genus is al-
most exclusively confined to the sea-beaches of the Atlantic
coast.

TYCHUS Leach.

T, sonome 2. sp.—Slender, convex, piceous; elytra, legs and antennz
testaceous; pubescence fine, moderate in length, sparse; integuments pol-
ished, impunctate. Head much narrower than the prothorax, distinctly
longer than wide, broadly rounded behind the eyes; the latter rather large,
prominent, coarsely granulate, at nearly their own length from the base;
surface transversely convex, transversely impressed behind the frontal

470 CALIFORNIA ACADEMY OF SCIENCES.

tubercle, which is transverse, convex and impressed along the middle; on a
transverse line passing through the anterior portion of the eyes there are two
minute, widely distant, punctiform fovew; antenna slightly longer than the
head and prothorax together, robust, strongly clavate, basal joint much
longer than wide, arcuate, second slightly narrower, quadrate, third nar-
tower, obconical, longer than wide, joints three to seven subequal, eighth
very slightly wider than long, ninth abruptly much witer, tenth still wider,
equal in length, ninth and tenth distinctly wider than long, eleventh wider
than the tenth, as long as the three preceding together, acuminate. Pro-
thorax widest slightly before the middle, as wide as long, strongly convex;
_ sides rather strongly rounded, feebly sinuate near the apex, more strongly
so near the base; the latter broadly arcuate, four-fifths as wide as the disk,
one-third wider than the apex; basal fovea minute, very near the margin;
lateral impressions feeble; along the basal margin between the median fovea
and the basal angles there are, on each side, two small punctiform fovea,
nearly as large as the median. Elytra at the humeri scarcely perceptibly
wider than the prothorax, at the apex nearly twice as wide as the latter;
sides evenly arcuate, together transversely truncate behind, convex, as long
as wide, two-thirds longer than the prothorax; each bifoveate at base; su-
tural stria deeply impressed; discal distinct, broadly impressed, terminating
slightly before the middle. Abdomen two-thirds as long as the elytra, much
narrower than the latter, parabolic in form; basal segment much longer than
the second; lateral border narrow, flat, rapidly attenuate from base to apex.
Legs rather long and slender; posterior tibizw arcuate toward apex. Length
1.25 mm.

California (Mendocino Co., 1.)

The specimen described is probably a male; the sexual
characters are very feeble, the fifth segment being longer,
feebly flattened, and broadly bilobed at apex. The species
is much smaller than either of the two previously described
from these regions, and the fourth joint of the maxillary
palpi has a long and distinct terminal process. The third
joint of that organ is elongate and clavate, the fourth more
strongly arcuate within, subsecuriform, elongate and strongly
compressed.

4 bipuncticeps n. sp.—Rather slender, convex, polished, impunctate,
piceous; elytra, legs and antenne pale rufous. Head moderate, slightly
longer than wide, convex; eyes large, convex, prominent, just behind the
middle; gens convergent, feebly arcuate, clothed with longer, dense pubes-
cence; base broadly arcuate; antennal tubercle much wider than long,
large, divided by a feeble canaliculation; antenne as long as the head and

NEW NORTH AMERICAN PSELAPHIDA. ATI

prothorax together, rather slender, basal joint as long as the next two to-
gether, subcylindrical, second narrower, second and third slightly longer
than wide, the latter slightly shorter and narrower, four to eight equal in
width, slightly shorter but scarcely narrower than the third, ninth wider,
nearly as long as wide, tenth wider than the ninth, wider than long, eleventh
distinctly wider than the tenth, ovoidal, acuminate, as long as the three
preceding together; on a line through the anterior portions of the eyes there
are two small, very widely distant nude punctures; fourth joint of maxillary
palpi dilated internally, truncate at apex, having a slender terminal process.
Prothoraz distinctly wider than the head, one-fifth wider than long; sides
strongly rounded just before the middle, convergent and very feebly sinuate
toward base; the latter evenly, feebly arcuate, four-fifths as wide as the disk,
one-third wider than the apex; the latter truncate; disk strongly convex,
with a row of small punctures along the basal margin, very feebly impressed
at each side near the base, with a small, deeply impressed, nude fovea in the
middle and very near the basal margin. JHlytra near the apex nearly twice
as wide as the prothorax; sides moderately divergent from base to apex,
arcuate; disk fully as long as wide, convex; sutural strize distinct, strongly
arcuate; discal fine, distinct, terminating at the middle; humeri rather
strongly tumid. Abdomen much shorter than the elytra, parabolically
rounded throughout; border narrow, rapidly becoming extinct; surface con-
yex and declivous posteriorly from the apex of the first visible segment; the
latter as long as the next two together, transversely very feebly convex.
Legs \ong, slender, simple; tarsislender. Metasternum broadly and strongly
impressed along the middle; posterior coxe rather widely separated. Length
1.4 mm,

California (Lake Tahoe 2).

The type specimen is a male, the under surface of the
abdomen near the apex being broadly and feebly impressed.
With this specimen I have associated a female, which dif-
fers considerably in the much shorter elytra, with more
strongly divergent sides; but the material is insufficient to
permit definite conclusions regarding its identity.

The individual facets or granules upon the surface of the
compound eyes are circular and very widely separated.

This species is very nearly related to sonome, but differs
in its slightly more robust form and slightly more trans-
verse prothorax, with more angulate sides. It occurs under
chips and bark slightly buried in grassy turf.

472 CALIFORNIA ACADEMY OF SCIENCES.

ACTIUM Casey.

Through the kindness of Herr Reitter, of Médling, Aus-
tria, who has sent me several representatives of Trimiopsis,
I am enabled to give the following statement, showing the
relationship of the latter with Actium, Trimiopsis being
represented by 7. Hggerst.

The maxillary palpi of Trimiopsis are long, the fourth
joint being more strongly dilated internally near the base,
and therefore distinctly securiform; while in Actium,as rep-
resented by pallidum, the palpi are shorter, more robust, and
with the outer joint ovoidal and acuminate. In 7. specu-
laris, however, the palpi are more robust and do not differ
so greatly from the form existing in Actium.

One of the most conclusive differences, however, is the
presence of a distinct discal stria, extending for one-half to
two-thirds the elytral length in Actium, and the complete
absence of this stria in Trimiopsis.

In Trimiopsis the isolated fovea at the base of each ely-
tra, between the discal and sutural strize, which is a con-
stant character of Actium, 1s completely wanting.

Several species of Trimiopsis have two basal abdominal
carine, these being very widely distant in TZ. specularis;
others, however,—eg.- Hygersi—are entirely devoid of the
basal carine. In Actium the basal carine are distinct and
rather approximate.

The species of Trimiopsis are much smaller than those of
Actium, and have the head relatively much larger.

Actium also appears to resemble, to some extent, the
much more minute African species, recently described
under the name Periplectus by Raffray,

It is probable that the species described from the east-
ern parts of the United States under the name Trimium
might more appropriately be referred to Trimiopsis, as the
Huropean genus Trimium has not yet been discovered with-
in our territories.

NEW NORTH AMERICAN PSELAPHIDA. 473

A. pallidum 2. sp.—Form rather slender, convex; pale flavo-testaceous
throughout, antennaz and legs slightly paler and less rufous; integuments
polished, impunctate; pubescence fine, short, subrecumbent, rather sparse.
Head small, very much narrower than the prothorax; as long as wide; eyes
rather large and prominent, somewhat finely granulated, at the middle of the
sides; gene distinctly shorter than the eyes, evenly rounded to the neck, not at
all prominent; base very feebly sinuate; occiput longitudinally impressed in
the middle; front having two round, impressed, spongiose fovez on a line
through the middle of the eyes, mutually twice as distant as either from the eye,
connected by a subangulate channel which is rather strongly impressed and
much wider than long; antenne short, one-half longer than the head, club
very robust, two basal joints subequal, slightly longer than wide, more ro-
bust than the funicle, joints three to seven moniliform, subequal, the former
slightly longer than wide, the latter slightly transverse, joints eight to ten
very short and strongly transverse, equal in length, acutely rounded at the
sides, the former twice, the latter more than three times as wide as long,
eleventh much wider, ovoidal, gradually acuminate, as long as the five pre-
ceding together. Prothorax widest at one-third the length from the apex,
where it is scarcely as wide as long; sides rather broadly rounded, feebly
convergent and nearly straight toward base; the latter evenly and rather
strongly arcuate throughout, fully four-fifths as wide as the disk, one-half
wider than the apex; disk convex, having at one-fourth the length from the
base a transverse, narrow, deeply impressed, posteriorly arcuate channel,
connecting the rather large, deeply impressed, spongiose lateral foveze and
continued posteriorly more than one-half the distance to the basal margin
by a canaliculate impression; along the basal margin, very near the edge.
there is a narrow deeply-impressed line. Hlytra at the humeri much wider
than the prothorax; sides feebly divergent, arcuate; humeri rather promi-
nent; together fully as long as wide; disk feebly convex, each trifoveate at
base; sutural stria fine, deep, nearly straight; discal proceeding from the
third fovea, fine, nearly straight, parallel to the sutural, slightly double at
base, vanishing at a slight distance before the middle; second fovea without .
trace of stria. Abdomen distinctly shorter, but very slightly narrower than
the elytra, rapidly declivous behind, parabolically rounded through its apical
half when viewed vertically; border narrow, slightly inclined; first segment
slightly longer than the second, having at base two fine, slightly divergent
carinze which are very short and distant by less than one-fifth the abdomi-
nal width. Legsslender. Length 1.2 mm.

California (Monterey Co.)
This species is abundant under decomposing vegetation,
near the margins of small streams.

A. politum n. sp.—Form slender, convex; bright testaceous, legs and
antenne slightly paler, more flavate, abdomen darker, castaneous; integu-

ATA CALIFORNIA ACADEMY OF SCIENCES.

ments polished, impunctate; pubescence fine, short, sparse. Head small,
as long as wide, distinctly narrower than the prothorax; eyes rather small,
at the middle of the sides, convex; gen distinctly longer than the eyes,
arcuate, not prominent; occiput feebly impressed in the middle; front havy-
ing two large spongiose fovex on a line through the posterior portions of the
eyes and mutually twice as distant as either from the eye, connected by a
subangulate impressed groove; antenne short, slender, scarcely one-half
longer than the head, club large, elongate, two basal joints more robust, sub-
equal, slightly longer than wide, joints three to seven moniliform, the latter
globular, eighth very slightly wider, a little wider than long, eight to ten
very gradually wider and more transverse, equal in length, the latter oval
and scarcely twice as wide as long, eleventh nearly twice as wide as the
tenth, cylindro-conoidal, acuminate, truncate at base, elongate, nearly as
long as the five preceding together. Prothorax widest at two-fifths the
length from the apex; sides rather strongly rounded, distinctly convergent
and feebly sinuate to the basal angles; base feebly arcuate, scarcely more
than two-thirds as wide as the disk, one-third wider than the apex; disk
convex, about as wide as long, crossed at one-third the length from the base
by a narrow impressed groove which is nearly straight; lateral foves large,
spongiose, deeply impressed; median posterior prolongation rather broadly
impressed; basal margin feebly impressed. Hlytral width at the humeri,
which are distinctly prominent, much greater than that of the prothorax;
sides very feebly divergent, evenly and strongly arcuate; together as long
as wide, transversely truncate at apex; disk feebly convex, each trifoveate at
base; sutural striz deep, feebly and evenly arcuate, rather distant from the
suture; discal feebly arcuate, parallel, vanishing very slightly behind the
middle, distinctly double at base. Abdomen distinctly shorter and narrower
than the elytra; sides parallel and straight at base, rounded behind; border
rather narrow; first visible dorsal with two fine subparallel basal carinze
which are nearly one-third as long as the segment and separated by nearly
one-fourth the abdominal width. Legs slender. Length 1.3 mm.

California (Mendocino Co. 1).
Kasily known by its dark abdomen, slender antennz and
smaller eyes.

A. robustulum n. sp.—Rather robust, convex, pale testaceous through-
out; integuments polished, impunctate; pubescence fine, short, subrecum-
bent, not dense. Head very small, nearly as wide as long, much narrower
than the prothorax ; eyes moderate, convex, prominent; gene distinctly
longer than the eye, not prominent, rounded; occipital fovew large, ona
line through the posterior portions of the eyes, mutually twice as distant as
either from the eye, connected by an impressed angulate groove; antennz
short and slender, scarcely one-half longer than the head, club gradual,
elongate, two basal joints subequal, slightly more robust, longer than wide,

NEW NORTH AMERICAN PSELAPHIDA. ATd

three to seven nearly equalin width, the former much longer than wide, the
latter distinctly wider than long, ninth to eleventh uniformly and rather
rapidly increasing in width, the ninth one-half wider than long, slightly
shorter than the tenth, the latter fully twice as wide as long, eleventh elon-
gate, accuminate, as long as the four preceding together. Prothorax widest
before the middle; sides rounded, convergent and feebly sinuate toward
base; the latter evenly and distinctly arcuate, four-fifths as wide as the disk
and one-half wider than the apex; disk convex, very slightly wider than long;
basal groove at nearly one-third the length from the margin, feebly, posteri-
orly arcuate, very deeply impressed; lateral fovez large, deeply impressed,
median posterior cusp-shaped prolongation large and Jong; surface broadly
and very feebly impressed anteriorly from the lateral fovexw, and with traces
of a narrow median canaliculation near the center of the disk. Hlytra at the
somewhat prominent humeri distinctly wider than the prothorax; sides very
feebly divergent, strongly and evenly arcuate; disk about as long as wide,
convex; sutural strize deep, arcuate; discal fine, distinct, nearly parallel, ex-
tending to or very slightly beyond the middle; intermediate basal fovea sim-
ple. Abdomen viewed vertically short and broad, three-fourths as long as
the elytra, distinctly narrower; sides straight, parallel, broadly rounded be-
hind; border rather narrow, inclined; first visible segment very slightly
longer than the second; basal carinw rather robust and flat, very feebly di-
vergent, less than one-third as long as the segment, distant by one-fourth
the abdominal width. Jegs moderate in length; femora robust, much more
arcuate externally and toward apex, posterior more slender. Length 1.4
mm.

California (Anderson Val., Mendocino Co. 1).

The type is apparently a male, the penultimate segment
being transversely and narrowly impressed; the terminal °
segment is flat, in appearance like a horizontal pygidium;
it is slightly longer than wide, oval, slightly more attenuate
behind, and entirely surrounded by the other segments.
The species is much more robust than the others here de-
scribed.

A. testaceum 1. sp.—Form slender, convex; pale testaceous throughout;
integuments polished, almost impunctate; pubescence very fine, short,
sparse. Head moderate, distinctly narrower than the prothorax; eyes
small, convex, prominent; gene not at all prominent, much longer than the
eye, rounded; occiput narrowly and deeply impressed in the middle; fovex
ona line through the posterior portions of the eyes, round, spongiose,
scarcely twice as distant as either from the eye, connected by an impressed
channel, which is more broadly arcuate than usual; antenna scarcely one-
half longer than the head, slender, nearly as in robustulum. Prothorax

A476 CALIFORNIA ACADEMY OF SCIENCES.

very slightly wider than long, almost exactly similar to that of robustulum,
except that the transverse basal groove is at scarcely more than one-fourth
the length from the base. Hlytra at the prominent humeri distinctly wider
than the prothorax; sides feebly divergent, strongly arcuate; disk convex,
about as long as wide; sutural striz strong, arcuate; discal fine, distinct,
terminating at the middle of the disk. Abdomen very slightly shorter and
much narrower than the elytra, longer than wide; sides nearly parallel,
straight, except in the apical fourth, which is parabolically rounded; basal
carine less than one-third as long as the segment, fine, exactly parallel and
straight, separated by slightly less than one-third the abdominal width.
Legs rather short and slender. Length 1.2 mm.

California. (Anderson Val., Mendocino Co. 1).

This species is very closely allied to the preceding, the
type specimen, which is apparently a female, is smaller,
much narrower, with a narrower, much more elongate abdo-
men and larger head. The form and position of the basal
carine differ in the two species, being distinctly stronger
and divergent in robustulum, and finer and perfectly parallel
in testaceum. Were it not for this character and the proba-
bility—because of the sexual characters—of the masculinity
of the small-headed type of robustulum, I should be per-
suaded to unite the two as very extreme specimens of a
single species, but at present this does not appear to be ad-
missible. Although both are from the same region, the
localities in which they were taken were widely different.

The four species thus far described differ from caliform-
cum, as described by LeConte, in the extent of the discal
strie, these being two-thirds as long as the elytra in the
latter. The number of species is probably considerable, as

scarcely any organized attempt has been made to collect
them.

EUPLECTUS Leach.

E. californicus 0. sp.— Form slender, parallel, depressed; dark testa-
ceous throughout, polished; pubescence fine, rather short, somewhat dense.
Head rather large, slightly wider than long; eyes small, convex, rather
prominent, at more than their own length from the base; gene rounded,
convergent, not prominent; base broadly sinuate; surface depressed,
coarsely, deeply and rather densely punctate; having on a line through the

NEW NORTH AMERICAN PSELAPHIDA. ATT

middle of the eyes, two small nude fovex, mutually scarcely as distant as
either from the eye, connected by a feebly impressed anterior groove; an-
tennal tuberculations small, rather prominent; antenna three-fourths as
long as the head and prothorax together, moderately robust, club moderate,
the joints nine to eleven gradually and uniformly wider, the latter oval, as
long as the three preceding together;-under surface deeply and densely
punctate, with an impressed fovea in the middle at the base, without long
erect setz. Prothoraz slightly shorter and narrower than the head, widest
at one-third the length from the apex, very slightly wider than long; sides
strongly rounded anteriorly, rather strongly convergent and nearly straight
to the base; the latter broadly arcuate, two-thirds as wide as the disk, very
slightly wider than the apex; the latter transversely truncate; disk feebly
convex, with aslightly elongate fovez near the center, a broad impression at
one-fourth the length from the base, and, on each side, a large rounded
deeply-impressed fovex, at two-fifths the length from the base, not connected
with the median impression; surface very feebly and not densely punctate.
Hlyira at the humeri slightly wider than the prothorax; sides nearly parallel,
distinctly arcuate; together very feebly sinuate at apex; disk depressed, as
long as wide, nearly one-half longer than the prothorax; sutural stria deep,
very feebly arcuate; discal fine, distinct, slightly arcuate, vanishing slightly
before the middle; each elytron with an isolated basal fovea near the sutu-
ral; surface very feebly, sparsely punctate. Abdomen as long as the elytra
and distinctly narrower; sides straight and parallel; border narrow; surface
feebly convex, finely, feebly and not densely punctate; first three visible
dorsals equal in length; first two each impressed in the middle of the base;
carinz very short and nearly obsolete. Legs short; femora not robust; tarsi
short and robust. Metasternum long, impressed along the middle. Length
1.3mm.

California (Lake Tahoe 3).

The tarsal claw has a very minute hair-like appendage
internally near the base, giving the appearance of a rudi-
mentary second claw, but as all the characters are precisely
similar to the Kuropean genus Euplectus, as seen in san-
guineus, signatus, Bonvouloiri, etc., much more, similar, in
fact, than most of our Hastern Euplecti, it is impossible to
believe that it belongs to a different group. I would pre-
fer rather to consider this a tendency to revert to the nor-
mal condition of Coleoptera, and to hold that similar ap-
pearances may occasionally be exhibited in the EKuropean
genus.

The type is a male, the sixth segment being deeply im-

AT8 CALIFORNIA ACADEMY OF SCIENCES.

pressed in the middle. The female does not differ appre-
ciably in form.

The occurrence of a genuine Euplectus near the Pacific
coast is a very interesting fact, as heretofore the genus has
not been discovered west of the Rocky Mountains. The
three specimens indicated were found under the bark of
fallen trees, and the species appears to be very rare. It
should be placed after conjlwens in our lists.

RHEXIDIUS n. gen. (Euplectini )

Tarsi with two unequal claws; antenne straight, basal joint not conspic-
uously elongate, widely separated at base. Posterior cox contiguous.
Prothorax without lateral teeth, having a median canaliculation, and two
large lateral fovece near the base connected by a fine transverse line. An-
tennz eleven-jointed, short; club long and slender, three-jointed. Mazxil-
lary palpi small, slender; third joint oval, slightly longer than wide; fourth
much longer than the three basal combined, slender, fusiform. First vis-
ible dorsal segment slightly longer than the second; second ventral in the
middle as long as the next three together; posterior margins of the posterior
segments strongly emarginate. Elytra with lateral subhumeral fovea and fine
carina.

This genus is founded upon a small Californian species,
bearing a great resemblance in many of its characters to
Oropus, but differing in the structure of the antenne and in
the complete absence of lateral prothoracic teeth. It be-
longs in some of its characters near the African genus Raf-
frayia, Reitter, but differs greatly in the pronotal sculpture
and elytral structure.

R. granulosus n. sp.—Rather slender and depressed, pale ochreous-tes-
taceous throughout, slightly shining; pubescence rather coarse, moderate in
length, not very dense. Head much wider than long; eyes far down on the
sides, rather small, feebly convex, at about their own length from the base,
coarsely granulated; base broadly sinuate; occiput feebly impressed in the
middle at base, having dorsally on a line through the middle of the eyes two
small, very widely distant, nude fovee, also near the apex a transversely
and feebly arcuate groove, terminating in minute fove which are connect-
ed with the occipital foveze by a finer groove; surface impunctate, rather
densely covered with small, round, strongly elevated tubercles; antennz
distinctly shorter than the head and prothorax together, basal joint but very

NEW NORTH AMERICAN PSELAPHIDA. A79

slightly longer than wide, cylindrical, second shorter, slightly narrower,
nearly globular, three to eight narrower, transverse, the latter twice as wide
as long, ninth and tenth slightly more than twice as long, much longer than
the eighth, nearly rectangular, the tenth very slightly the wider and longer,
eleventh scarcely visibly wider than the tenth, very elongate and slender,
gradually acuminate and as long as the five preceding joints combined.
Prothorax but very slightly wider than the head, widest in the middle;
sides near the basal angles just visibly sinuate, in the middle strongly
rounded, near the apex very feebly sinuate; base broadly arcuate, two-thirds
as wide as the disk, one-half wider than the apex; disk as wide as long,
moderately convex, covered not very densely with small tubercles; median
canaliculation rather fine, equal, terminating near the base and apex; lateral
fovee small, deeply impressed, spongiose, at a little more than one-fourth
the length from the base, connecting groove transverse, straight, very fine.
Hlytra slightly longer than the prothorax, at apex one-half wider than the
latter, distinctly wider than long; humeri not at all prominent; together
transversely truncate behind; disk feebly convex, rather sparsely and more
coarsely tuberculate, each with three basal fovez and four striz, one evenly
and feebly arcuate, two and three feeble, nearly equal, one-half as long as
the elytra, four stronger, one-third as long as the elytra. Abdomen very
slightly wider and longer than the elytra; sides arcuate; border rather strong,
inclined; surface rather strongly convex, scarcely visibly tuberculate, Legs
rather slender. Length 1.0 mm.

California (Alameda 4).

The sexual differences are apparently very feeble, the
terminal segment in the male being feebly impressed. The
mesosternum is bicarinate.

OROPUS Casey.

0. montanus n. sp. — Form slender, rather depressed, uniform dark
rufo-testaceous throughout; integuments polished, not perceptibly punctate;
pubescence fine, rather long, not dense. Head triangular, shorter and nar-
rower than the prothorax; eyes rather small, not very prominent, at slightly
more than their own length from the base; genz strongly convergent, feebly
arcuate; base broadly sinuate; base of occiput longitudinally impressed in
the middle; occipital foveze deep, distant, on a line through the posterior
limits of the eyes, connected by a narrow, deeply impressed, arcuate groove,
much shorter than wide; antenne short, robust, distinctly shorter than the
head and prothorax together, club elongate, rather feeble, joints three to
eight transverse, the former slightly wider than long, the latter more than
twice as wide as long, ninth and tenth joints twice as wide as long, nearly
rectangular, tenth just visibly wider and longer than the ninth, eleventh

480 CALIFORNIA ACADEMY OF SCIENCES.

distinctly wider than the tenth, nearly three-fourths longer than wide,
conoidal, acuminate. Prothorax widest in the middle, where the sides are
strongly rounded, thence strongly convergent toward base and apex, very
feebly sinuate near each limit; base broadly arcuate, scarcely two-thirds as
wide as the disk, one-half wider than the apex; the latter feebly arcuate and
less than one-half as wide as the disk; lateral teeth minute, in a transverse
line with the lateral fovez; the latter deep, at slightly less than one-third
the length from the base, connected by a fine, posteriorly arcuate groove;
median canaliculation fine, crossing the transverse groove; obsolete near the
base and apex, not at all dilated except near its basal limit; disk about as
long as wide. LHlytra scarcely one-fifth longer than the prothorax, at apex
nearly one-half wider than the latter; disk distinctly wider than long, feebly
convex; stria one nearly straight, two slightly arcuate, united with one at
one-third the length from the apex, three two-thirds and four one-half as
long as the elytra respectively, all deeply impressed. Abdomen nearly as
wide as and distinctly longer than the elytra. Legs rather short and robust.
Length 1.8 mm.

California (Placer Co. 1).

Described from the female. It can very readily be dis-
tinguished from all the species previously known by its
slender form, short elytra and peculiar disposition of the

elytral striz.
SONOMA Casey.

S, corticina 0.sp.—Linear, depressed, pale testaceous throughout;
pubescence fine, rather short, not dense. Head slightly wider than long, a
little shorter and narrower than the prothorax; eyes small, at the middle of
the sides; genze long, rounded, longer than the eyes and nearly as promi-
nent; front feebly convex, impunctate, having, at nearly one-third the length
from the base, two small nude punctiform fovez, mutually slightly less dis-
tant than either from the eye, and, at the vertex, behind the line of the an-
tenn, a large, deep circular fovea which is completely nude; antenne one-
third longer than the head and prothorax together, slender, feebly clubbed,
first joint much longer and slightly more robust than the second, the latter
nearly one-half longer than wide, oval, joints three to eight moniliform,
gradually shorter, the latter slightly wider than long, joints eight to ten
similar in form, gradually slightly larger, eleventh slightly wider than the
tenth, a little longer than wide, obtusely acuminate, not as long as the two
preceding together; under surface transversely and feebly impressed just
behind the mentum, and more deeply so along the basal margin; fourth
joint of the maxillary palpi longer than wide, compressed, oval, having a dis-
tinct terminal process. Prothorax widest in the middle; sides broadly
rounded to the neck, convergent and distinctly sinuate near the base; disk

NEW NORTH AMERICAN PSELAPHIDA. 48]

slightly wider than long, feebly convex, having a transverse anteriorly arcu-
ate impress.on near the base which terminates laterally in two small puncti-
form fovex and which is more deeply impressed in the middle, also just be-
fore the middle two minute punctiform fovez, separated by one-fifth the en-
tire width, and at each edge at one-fourth the length from the base, a large
disconnected deeply impressed fovea, the impression being continued more
feebly to the basal angles. Hlytra depressed, at the humeri slightly wider
than the pronotum; sides nearly parallel, more strongly arcuate behind; to-
gether truncate at apex, nearly as long as the head and prothorax together;
sutural stris deeply impressed, beginning at a slight distance from the base;
discal broadly impressed, vanishing near the middle, coarsely foveo-punc-
tate; between this and the sutural a few foveate punctures near the base ar-
ranged longitudinally. Abdomen slightly longer and wider than the elytra;
border wide, slightly inclined; first visible dorsal much shorter than the sec-
ond, having near the apex a transverse interrupted spongiose line. Legs
rather short and robust. Length 1.4-1.6 mm.

California (Mendocino Co. 8).

This species was found rather abundantly under the bark
of fallen trees in the Anderson Valley; it differs from par-
viceps in its larger head, and from isabelle in color and in
its less robust form.

S. cavifrons 2. sp.—-Slender, depressed, pale testaceous throughout; pu-
bescence fine, short, suberect, not dense; integuments polished. Head small,
much smaller and narrower ‘han the prothorax, as long as wide, eyes moder-
ate in size, prominent, finely granulate; genz convergent, rounded, not at
all prominent, as long as the eyes; base feebly sinuate; surface impunctate,
having posteriorly two small round feebly impressed fovez, mutually slightly
less distant than either from the eye, and, just behind the strongly elevated
transverse frontal ridge, a longitudinally elongated, very deeply excavated
fovea which is slightly spongiose and more attenuated posteriorly; antenns
slender, slightly longer than the head and prothorax together; first joint
longer than wide, robust, oval, second shorter, less robust, oval, one-half
longer than wide, third small, narrowest, four to seven subequal, much
larger than the third, joints three to seven slightly longer than wide, eight
as wide as long, nine and ten slightly larger, very little wider than long,
eleventh slightly wider than the tenth, longer than wide, acuminate, shorter
than the two preceding together. Prothorax widest at one-third the length
from the apex, where it is distinctly wider than long; sides strongly rounded,
convergent and sinuate toward base; the latter broadly arcuate, three-fourths
as wide as the disk. more than one-third wider than the apex. EHlytra at the
humeri distinctly wider than the prothorax; sides feebly divergent, more
strongly arcuate behind; tozether slightly longer than wide, as long as the

482 CALIFORNIA ACADEMY OF SCIENCES.

head and prothorax together, depressed; sutural series of four impressed
fovez at the base; the sutural stria deeply impressed and continuous only
from the fourth fovea; discalimpression coarsely foveate, terminating before
the middle; between them a basal series of two or three fover. Abdomen
as wide as and slightly longer than the elytra; border wide. Legs short
and rather slender. Length 1.9 mm.

California (Mendocino Co. 1).

The pronotal foveze and spongiose band of the abdomen
are nearly as in corficina. This species is abundantly dis-
tinguished from the preceding and from isabelle, Lec. by its
smaller head and pale color respectively, and from parviceps
Mikl, which it must more nearly resemble, in its smaller
size. The present species was found with the preceding
under bark, and, as the Alaskan form inhabits grassy places,
the two are probably distinct.

S. isabelle Lec.—Two specimens of this species, collected by Mr. C. Fuchs,
at Alameda, differ greatly from those here described in the shorter, more ro-
bust antennx, with more transverse joints, in the intense black color with
testaceous elytra, and in the complete absence of the two discal punctures
of the pronotum. They were found in decomposing vegetable mould. |

EXPLANATION OF THE PLATE.

The accompanying plate is somewhat experimental, the figures being re-
productions by means of photography and gelatine printing, of shaded lead-
pencil drawings. Should this attempt be deemed successful, the process
must assuredly become popular among entomologists, as it is far easier and
less trying to the eyesight to make satisfactory drawings in soft pencil than
in ink stipple.

Fig. 1—Wisazis cincinnata Cas. Fig. 6—Tychus sonome Cas.
Fig. 2—Biotus formicarius Cas. Fig. 7—Actium pallidum Cas.
Fig. 3—Lutrichites (Zimmermanni ?)Lec. Fig. 8—Rhexidius granulosus Cas.
Fig. 4—Oropus interruptus Cas. Fig. 9—Thesium laticolle Cas.
Fig. 5—Bryaaxis texana Cas. Fig.10—Sonoma corticina Cas.

Novte.—The drawings are taken from typical representatives in all cases except Hu-
trichites Lec. and Thesium laticelle Cas., which I have identified from the original descrip-
tions. With reference to the former, it may be stated that the specimen figured agrees
very well generically, but not so well specifically, with the description of Le Conte.
For example, the apical fovea of the front is stated to be smaller than the occipital in
Zimmermanni, whereas in the representative figured it is in the form of a broad, indefi-
nite impression without trace of fovea. The specimens here figured were found at
Austin, Texas.

XVI

Plate

Balletin Gal, Head, Sa. Vol. 2

QL Casey, Thomas Lincoln, 1857,
DIO) — 1925.

P8C3 On some new North Ameri-
Ent. can Pselaphidae.

SMITHSONIAN INSTITUTION LIBRA

HL i

0356591
ae oe P8C3
On some new Bost American Pselaphidae /