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Psyche 7:303-305, 1894.

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PSYCHE.
NOTES ON THE HABITS OF TRYPOXYLLON RUBROCINCTUM AND TRYPOXYLLON ALBOPILOSUM,
BY GEORGE W. PECKHAM AND ELIZABETH G. PECKHAM, MILWAUKEE, W1SC. When we went out to our summer
cottage, in tlie last days of June, we
found n-niny littlc wasps of the species TryfoxyZZon rubrocinch busily
working about a brick smoke-house on
the place. Closer examination showed
that in the mortar between the bricks
were many little openings leading back
for a considerable clistimcc, which were occupied by the wasps. It would seem
that these holes were excavated by some
other agcncy than tlie wasps themselves
as they were so much to6 deep for their
purposes that before using- them they
built a mud partition across the open-
ing about an inch from the outside of
the wall. Later on we found nests of
the same species in the posts which
support an upper balcony of the cottage, and here, too, the wasps made use of
holes which were alrendy excavated.
We also found in these posts nests of
Trypoxyllon albopilosztin and during
July and August we kept a close watch
upon tlie comings and going of our little neighbors.
They were very good-tempered little
creatures, never resenting our close
proximity nor our interference with
their housekeeping. By working hard'
they could prepare n nest, store it with spiders and seal it up, all in the same
day. This we have seen them do in
several instances. In other cases the
same operation takes tin-ee or ~OLII*
daj s.
With both species, when the prelimi-
nary work of cleaning the nest and
erecting the inner partition has been
performed by the female, the male
takes up his station inside the cell fac- ing outward, his little head just filling the opening. Here he stands on giifird
for the greater part of the time until
the nest is provisioned and sealed up,
occasio~~ally wrying the monotony of
his task by a short flight. As a usual
thing all of the woik is perfoimed by
the femiile, who applies herself to hei* duties with greater or with less industry according to her individual character;
but the male doubtless performs an ~ITI- portant office in protecting the nest
from parasites. We have frequently
seen him drive away the brilliant green
CJzrysis fly which is idways waiting
about for a chance to enter an un-
gullFhded nest. On these occasions the
defence is carried on with great vigor,
the fly being pursued for some dibtance




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304 PSYCHE. [November 1895.
into the air.
There are usually two or
three uninated males flyingabout in the
neighborhood of the nests, poking their
11e;ids into unused holes, and occasion- ally trying to enter one that is occupied, but never so far as we have seen, with
any success, tlie male in charge being
always quite ready and able to take care of his rights. The males, however,
never made any objection when strange
females entered the nest as tlicy some-
times did by mistake, nor did the females object to the entrance of a strange
nule when the one belonging to tlie
nest happened to be away, but in such
cases the rightful owner, on his return, quickly ejected Hie intnuler. We often
aniused ourselves, while we were watch-
ing the nests, by approaching the little male, as he stood in his doorway, with
a bhde of grass. He always attacked
it valiantly, and sometimes grasped it
so tightly in Iiis mandibles that he could be drawn out of the nest with it.
When the female returns to the nest
with a spider the male flies out to make way for her, and then as she goes in lie alights on her back and enters with her. When she comcs out again she bungs
him wit11 her, but he at once re-enters, and then, after a moment, comes out
and backs in, so that he faces outward
as before.
In one instance, with rubrocinctum,
where tlic work of storing the nest had
been delayed by rainy weather, we saw
the male assisting by taking the spiders ' ?
from the female as she brought them
and packing tlieni into the nest leaving her free to hunt for more. This was
an especially attentive little fellow, as he gunrded the nest almost continuously
for four days, the female sometimes be-
ing gone for hours at a time. On the
last day he even ~evisited the nest three or four times after it had been sealed
up.
It is upon the female that the heaviest
part of the work devolves. As soon as
she has put the nest in ordei she begins the anluous task of catching spiders
wherewith to store it. It usually takes
them from ten to twenty minutes to find
a spider and bring it home, but they
arc sometimes absent for a much longer
time. When the spider has been carried
to the nest the process of packing it in begins. This occupies some time and,
apparently, a good deal of strength, the femde pushing it into place with her
head with a total disregard of its coin- fort, ;ill the spiders that are caught be- ing pressed and jammed together into a
compsict mass. While she is busied in
this way she makes a loud cheerful
humming noise like that made by the
blue and yrllow mud-daubers, as, stand-
ing on their heads, they pither their
loads of mud. The n~niiber of spiders
brought seems to depend upon their
size, in which quality they vary greatly, the largest ones being six or eiglit times as large as the smallest. Rzcbrocinctum
fills licr nest with from seven to twelve, while the larger cflbopilosutit bung's as many as twenty-five or thirty. Those
that we examined represented many
different genera, and even different
families, although they were usually
Epeiridae.




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November iSmi.1 PSYCHE. 305
In a number of cases, after several
spiders h;id been stored, we ~ently drew tliern out with a bent wire. In one
nest in which there were five spiders,
we found, two hours after tliey had been stored, that three were alive and two
were dead. In another which the wasp
had just begun to seal up were ten
spiders. Three of these were injured
in being drawn out. Of the remainder
four were alive and -three dead. Ou
the anterior part of the dorsuin of one
of the living spiders was the egg. It
had probably been fertilized as the
female carried the male into the nest
on her back.
When a female returns with her load
lie usually hunts about for a few mo-
ments before finding her nest, often
enterin: two or three that are empty or
are occupied by otherwasps by mistake,
so that it. would seem that their sense
of locality is not very strongly de-
veloped.
After the storiugprocess is coinplekxl
the female seals up the nest with mud.
In the case of one rubrocinctum that we
were watching she began to close the
opening at 4.43 P.M. mid finishcd her
work just thirty minutes later. In this
time she made ten journeys for mud
bringing it in pcllcts in her mandibles. In another case, also a rubrocin1+7mz,
the female, after bringing so many
spiders that the cell was full up to the very door (which we saw in no other
case), went away without closing it and
never retrrned. The male seemed
une;isy at her conduct and several times flew away, staying an hour or two and
then returning ; but after a time he too deserted the nest. Whether some evil
fate overtook the female or whether
there was some failure of instinct on
her part can only be conjectured, but
the latter hypothesis is not untenable,
since out of twenty-six nests that we
hail under observation three were
cleaned out and prepared and were
then sealed up empty. We have often
found similar cases among the nests of
the blue mud-dauber wasps where it is
not a very uncommon thing for the
absent-minded fei~~iiles Lo build their
pretty little cylindrical nests with in- finite care and patience and then to
seal them up without putting anything
inside.
One afternoon as we sat, literally, at
our posts, a female of albopilosunz came lio~nn~ing along looking- very important and cticrgetic, as though she had
planned beforehand exactly what to do.
She entered an empty hole, head first,
and at once began to gnaw at the wood,
kicking it out backwards with consid-
erable violence. After a few minutes
she changed her method of work, and
began to carry out loads of wood dust
in her mandibles, drop pin,^ it in little showers just outside the nest, and then
hastening back. In forty ~ninutes she
carried out, in this way, upwards of
fifty loads. She then flew away, but
retm neil in ten minutes with a nxile.
She alighted, he took his place on her
back and they went in together.
After a time they came out and both
flew away, but the next morning they
came back am1 the ntxt was stored.




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306 PSYCHE. (November 1895.
In this species (alb~$iZo.wwz) the . We sometimes found the parasitic male does not always come out of the Melittobia fly in the nebts of ruirocinc- nest when the female brings a spider. tm, and from two nests we reared tlie Perhaps the nest is enough larger than common fly Pachyophtha/må´u auri- in rubrocinctum to accommodate them
both comfortably. As a usual thing,
however, he enters on the back of the
female. The spiders brought by albo-
filosum arc larger than those used by
rzibroc~~ctzcm. They sometimes bring
such heavy specimens of Epeira insul-
aris that they are carried with difficulty, the wasp alighting and dragging the
spider into the hole instead of flying
directly in, as usual.
Mr. W. Ashmead has noted that
albopilosum stores its nest with aphides but in the cases that we observed they
used only spiders. There can be no
mistake on this point as we more than
once took the spider from the wasp as
she was entering the nest. In a recent
letter Mr. Ashmead says that his notes
were made in the field, and that it was
probably a case of mistaken identity on
his part.
from.
We do not know how many nests
are stored by the fcmalc in one season,
nor the length of time taken in the
development of the young. Two nests,
scaled up on June 30 and July I are at
the present time, August 31, still un-
opened.
The interest of the wasps in family
affairs seems to flag in the second week of August and we saw no new nests
started after the fifteenth, so that it is probable that after that time the hard
wor1~in";ittle creatures enjoy a well
earned holiday on the blossoms of the
aster and the golden rod.
We are under many obligations to
Mr. W. H. Ashmead for his kindness
in naming for us both the wasps and
their parasites. His name is a suffi-
cient guarantee for the correctness of
the identification.
THE LARVA OF HARRISINA CORACINA CLEMENS. BY HARRISON G. DYAR, NEW YORK, N. Y.
Mr. T. D. A. Cockerell has sent me larvae of a Harrisina found on Vitis vim/era at Las Cruces, New Mexico. Mr. Cockerell
takes the moth of -//. coracina commonly on the same vines, and also a few H. metalfica; but he does not think that these are the larvae of the latter, as they are so much more rare. With this conclusion I agree, as the larvae differ too much from our H. ameri- cana to be those of the closely allied H. mefallica.
La?.va.
Shaped as H. americana, thick,
flattened, the head retractile.
Yelfbw; cer-
vical shield, warts on joint 2, a band on joint 3 covering the three upper warts and the two lower ones also black; a band on joint 4 and on 5 to wart vi; a M d on joints 6, 8, 10, 11 and 12 to the spiracle and the anal plate black, including the short hairs. Purple patches extend between the bands on joints 5 and 6, running forward to cover the lateral area of joint 4 to the band on that



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