Article beginning on page 271.
Psyche 7:271, 1894.

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August 1895.1
PSYCHE.
HABITS AND PARASITES OF STIGMUS INORDINATUS FOX. BY A. DAVIDSON, M.D., LOS ANGELES, CAL.
Judging from the numlier of tun-
nels excavated by this
species in soft
stemmed plants and friable rock, it must he somewhat common in this vicinity,
akho~~gh on account of the small size
and rapid flight it is very seldom seen. The only time 1 have ever seen it flving was when watching near their excava-
tions, at which time the wasp with its
prey may be easily captured. 'N'iey
usually build tlicir cells in tunnels cx- cavated in tlie stems of the
bramble,
black mustard, dock, or other pithy
plants; but not infrequently they m;iy
be found in burrows in the soft sand-
stone abounding in this district. The
plant-stems invariably chosen for ti nest- ing site.arc those alreadysevered, or
broken sufficiently to expose the pith.
In the center of this a tunnel of varying depth is exeiivatetl. I hiive a specimen in my possession in which this tiny
insect hns formed a tunnel 12 inches
deep and built and provisioned lliercin
30 cells. The latter measure on an
average one-fourth inch in. length by
one-sixteenth in width; but both are
variable, the width frequently being;
oneeighth of an inch. This wasp storrs
its nest with the common aphis, 20 of
which are on an average required to
provision each cvl!, The partitions
between the cells are composcd of pith
aiid vary in thickness. From speci-
mens which I secured in the autumn
the mature insects issued in February
and March, but the discovery of freshly
made cells in February :ind throughout
the summer gives me the impression
that while the majority- of the mlults
issue in the spring, yet they are more
or less active all the year round, in
which respect they are unique among
the native hymenoptera of my acquain-
tance. The larvae spin no cocnons the
light yellow pupa lying on its back in
the cell. Of the parasites, but two
species have been bred thus far; viz. :
O?IZ&LS iridescens Nort., and a new
species of Eiiry1:oma. Of the former
only two specimens were seared, from
separate cells ; both had pupated when
discovered in February, and hatdied
out March 14. Of Hie Eiirytoma, of
which a description has been kindly
furnished by Mr. Ashmead, a dozen
specimens were bred. Each occupied
a separate cell which showed no trace
of wasp remains; thcy spun no co-
coons, and were about two weeks later
in hatching out than the wasps in the
same burrows.
Mr. Ashmead's description of the
new Enrytoma is as follows : -
E?6~ytuma .st'f,pi Ashm. 11. sp.
2. Length 3 min. Black, ~11nbi1icately
punctate, clothed with sparse white pile; an- tcniiae entirely black; apical half of anteridr femora, tlicir tibiae, except a black stripe outwardly, and ;ill their tarsi, except the last



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272 P,s'2THE. [A~ignst 1895.
joint, knees of middle and of hind legs and the tips of their tibiae, honey yellow. Wing's hyaline, the veins brown, the marginal vein linear but rather slout, twice as long as the stignnal, the post-marginal slender, a little longer than the stigma]. The flagellum is about three and a half times as long as the ;cape; the funicle 5-jointed, the first joint the longest, not quite twice as long as thick, tlne following joints imperceptibly shortening-, submonilifoi-111 ; club ^-jointed, a little longer than the first two funicularjoiiits united, the joints closely conjoined. Thorax as in 7?. diostro-f'Jii. Abdomen conicalIy pointed, subcompressed, nearly one-half longer than the head and thorax united, smooth and pol- ished, except segments 6, 7 and g which are finely shqreened from some microscopic
punctures and bearded will1 white hairs. 8. Length 2.5 mm. Agrees with the $!
in color, but the funicular joints are incised and pedicellate at tips, the thickcncd portion being furnished with two whorls of long
white hairs, some of which are as long as the joints, the latter very gradually decreasing in length; the clnb is as long as the first fun- icular joint, but slenderer; while the body of the abdomen is sinall, compressed anil as viewed from the side triangular in outline attached to the nietnthorax by ;i long petiole which is finely sculptured or shfigreened and nearly as long as the body of the abdomen. PRICKLY LEAF-GALL OF RHODITES TUMIDUS ON ROSA FENDLERI.
BY C. 11. TYLER TOWNSEND, BROWNSVILLE, TEXAS. A few miles to the north of Ojo
Calicnio, on the Hot Springs reserva-
tion, in Socotro County, New Mexico,
some spherical prickly galls were
found in bnnelies on the leaves of ;I
wild rose, June 18, 1892. They were
the size of very large peas, reddish and greenish, anil covered with prickles
One of these galls that was opened
Dec. 13, 1892, contained a. whitish live hytiienopterous pupzi, which was some-
what active. This >\as the pupa of the
gall-maker, Rhoditrs twnidus Bass.
Descri'ption offfall,-Diameter 3 to g mnn. Usual size, 6 to 8 mm. Globular, or sub- globular, covered with prickles on upper half, prickles mostly directed upward especially the more superior ones which are from I to 1 mni. long, those on sides much shorter. Color brick-reddish above, and pea-green below, indicating the surface that has been exposed to the sun and that which has been sheltered therefrom. Growing in bunches, from 2 to 10 in a b~~nch, rarely singly. Borne always on
upper surface of leaf, some-
times three on the same. very small leaf which is thus almost obliterated,
sometimes
borne on petiole of leaf, often double.
Gull
coriLtiiniuga single large perfectly round ciiv- ity, lined with a very thin gefinisli lining, wiilts 11 mm. thick in enll of 8 mm. extermil diameter, leaving cavity
about 52 inin. in
diameter. Walls porous, minutely cellular, a cross section appearing- finely reticulate under lens, the lining of cavity sharing this appear- ance. The walls xveragc I UIIII. in thickness. Each gal1 contains but a single occupant. The double ones
never communicate inside.
The gcill-fly emerges by a circular hole gnawed in one side of the gall about 14 inin. in diameter.
Described from $3 galls. ' From two
of these galls, two gall-flies had




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