T. D. A. Cockerell.
A New ee of the Genus Emphor.
Psyche 20:107-111, 1913.

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19131 . Cocke~ell-A Nm Bee of the Genus Ernphm A NEW BEE OF THE GENUS EMPHOR.
BY T. D. A. COCKERELL,
University of Colorado.
Mr. C. T. Brues has kindly sent me three females of a species of Emphor, collected by Miss Louise Nichols at Cape May Pt., N. J., Aug. 25,1912. To my surprise, they are not E. binnbi.formis but represent a new species.
Emphor fuscojubatus sp. nov.
9
Like E, homb$orrni~ (a cotype from Georgia compared) but differing as follows: hair of vertex dark rufofuscous, instead of being ochreous like that of the thorax; hair of thorax paler, not so red; hair of middle of front fwcous instead of whitish; scape not red at apex; thiid submarginal cell conspicuously longer; hind margin of first abdominal segment narrowly pale and pellucid; wings perhaps rather paler,
This is probably the Empho~ bomb$ormis of Smith's New Jersey list.
, SOME OBSERVATIONS ON THE NESTING HABITS OF THE MINING BEE? EMPHOR FUSCOJUBATUS Ckll. These observations were made during the last week of August, 1912, at Cape May Point, N. J., by Mr. Reynold A. Spaeth and myself. The bees collected were thought at first to be Emphor bombiformb Cress., but a closer examination by Prof. T. D. A. Cockerell revealed the fact that they were sufficiently unlike E. bdi.formi$ to be classed as a new species, named by Prof. Cockerel1 Emphr juscojubatus, and differing from the other species chiefly in the color of the hair on various parts of the body and in the greater size of the third submarginal cell of the wing. It is a member of the family Apide.
By the side of a road, for a distance of about one eighth of a mile, .
in soil consisting of a mixture of clay, sand and pebbles, numerous nest openings were discovered and between about ten A. M. and four P. M. many bees flying in and out. The nest is begun as a semicircular depression? the soil being moistened by a fluid from



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108 Psyche [June
the mouthy loosened by the mandibles, and ejected sidewise by the first and second pairs of legs. As the depression increases in depth, it is surrounded by a wall of the moistened earthy reaching a height of about one centimetre, the posterior end of the abdomen being used as a trowel in its construction.
At frequent intervals the bee stops worky and after an absence of thirty seconds or soy returns. Our curiosity aroused as to the reason for these frequent excursions, we followed one individual in her flight and were led to a small pond about seventy-five yards away. Here numerous bees were discovered floating on the sur- face with legs outstretched, presumably sucking up into their crops a supply of water for use in making the nest. By its aid the clayey soil is formed into pellets, passed under the body probably by means of the tibi61 spines and kicked out at the entrance by a sudden jerk of the last pair of legs, most comical in the impression it produces of business like intention. The force of the jerk is often considerabley as the pellets are thrown several inches from the mouth of the nest.
Less than twenty-four hours is occupied in the construction .of the nest. One begun at twelve thirty P. M. was three inches deep at four, the same day. The following morningy between six- thirty and seven, the bee was observed entering, her hind legs and body heavily laden with flocculent masses of pollen. She remained within for one minute, presumably packing the polleny came out and was gone for five to six minutes, returning again laden with pollen. Sometimes the load is so superabundant that fragments of it will be dropped on the ground near the entrance. If the weather were cloudyy the time was lengthened, more than ten minutes being required for collection of the pollen'. After a final
trip she remained within for a longer timey i.. eSy twenty minutesy possibly occupied in laying an egg. The nest is completed by gnaw- -
ing away the raised rim of earth about the opening. Usually the
surrounding pellets are also drawn in by the first pair of legs, the earth thus filling and closing the entrance. A nearly circular
depressiony howevery marks the sitey for the earth is not filled in level with the soil surface.
On digging the earth away from the nest cavityy a considerable mass of fermenting pollen of sour smell was found and on it a single, slightly curved eggy six mm. in length.
The pollen is collected,




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apparently only in the early morning hours, for no bees were seen bearhg pllen in the middle or latter part of the day, Many plants were blooming in the vicinity, wild Compositxe and h&- nos=, dm cdtivated meet peas md morning glories, but uone of them were visited by the bees. Since the heavy, sticky mwes brought back by them resembled in appmance the pollen of Hibiscus ~o~chatu~, which grew abundantly in the aw~ps not far away* it was suspee~ that this plant might be the source of supply. A comparison under the miemscope of Hibiscus p01h with some taken fmm a nest proved this f~ be the ewe. Although the behavoir of the bees comesponds in general to the foregoing description, some variation was observed. As is oft- the case with solitary waps, nests my be begum and abandoned before comp!etion. The wall of earth wound the entrance is more m&uUy built in some nests thm in others, and the distance to which the pellets are thrown dso varies. Individual diffemca in the ease with which the nest was recognized were also noticed. Some fly with astonishing directness and rapidity io the opening, while others alight at the wrong spot and appear confused. Bees sometimes enter nesb not their own, and, on discovering the mis- take, hurriedly out. Before emerging it is usual for the insect ta stop a moment at the opening, moving the head from side t~ side as if reconnoitring. Slight movement or noise in the neigh- borhood will muse her to jerk back inta the nest, but after a short interval, she slowly reappears, agah reconnoitres md fies off. Individuals differ in this respect dso; some appear more timid &an others.
.
On Nov. 99, 1 again visited the place, in order ta determine if possible how the bees passed the winter. No txace m&hg of
the depressions marking the site of the nests, 1 WEIS obliged to dig at random. The quest proved not entirely fruitless and the mmns were obtained conhhhg lm~. The cocoon is made of demely woven silk entangling many left over pollen grains and lined with a brownish varnish-like substance, well adapted to keep out the dampness. The Ia~gest of the three meamre 8 little over two centimetres {about twenty the m. by thirteen, the smallest abut khkken mm. in each dimension and the third about sixten mm. by thirteen mm, This last was broken in moving it from the soil, It contained a small larva not quite a emti-



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110 Psyche [June
metre long.
The remaining two cocoons were buried in soil con- tained in a tin box and when next examinedy Dec. 2gY the larva within the larger cocoon was found dead. The small heady bear- ing distinct black jaws was bent under the body as was also the posterior end. The body nearly equalled in length the longer dia- meter of the cocoon. As the male of the closely related speciesy E. bombiformis is smaller than the female, the most probabl ,explanation of the difference in the size of the cocoons is that the larger ones contain females, the smaller ones males. Since writing the foregoing, I have discovered in the Journal of the N. Y. Entomological Society for Dee. 1911y an article entitled ccContributions toward the Life History of Emphor bombiformisy" by John A. Grossbecky a record of observations made at Arlingtony N. J. The account does not in all respects correspond to the ob- servations made on E. fuscojubatusy and as it would be interesting to know whether the two behave differently because they are differ- ent species or because of difference in the environment, I thinky it worth while to call attention to the nature of the discrepancies. Grossbeck describes the bee as beginning the nest by digging with the fore legs in a thin layer of sod, brushing the fragments away with the hind legs and turning around constantly. when the hole is one-half an inch deep, soil is reached and a different method of working begun. The soil is now moistened with saliva, small pieces bitten off with the mandibles, where, with the assistance of the abdomen, it is placed at the entrance. No doubt the differ- ence in the manner of beginning to dig is due to the difference in the character of the soil, for in the location chosen by E. fuscoju- batus there was practically no sod and the bee commenced to work at once on a sandy surface.
The bees at Cape May Point seemed but little disturbed by our presence at any timey except that when reconnoitring at the mouth of the nesty a sudden movement or noise would cause a hasty re- treat. We were able to sit quietly very close to the opening with- out interfering with their comings and goings. On the other handy the bees at Arlington showed great commotion, flew wildly about, buzzed loudly and were so reluctant to enter their burrows that a group of a little more than twelve were increased to about thirty. Quiet ensued in about five minutes and later in the day



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19131
Nichols-Observations on the Nestkg ,Habits oj the Mining Bee 11 1
they were not disturbed by human presence. The observer re-
mained, however, about two feet away from the nest openings. More than once, also, Grossbeck noticed bees showing animosity toward each other. On one occasion when a pollen-laden bee returned to find its burrow already occupied by another, also pol- len-bearing, there followed a really dramatic episode. Both came out hurriedly, buzzed around, clenched, rolled on the ground, separated and were then lost to sight. Presently one returned, presumably the rightful owner, and rapidly removed three loads of pollen, two of which were dropped not far from the entrance and the third was carried farther away. The colony of E. fusco- jubatus, on the contrary, so far as we could tell lived together, mutually harmonious, yet independent. It is well known that some strains of Apis mellijka show much greater excitability and pugnacity than others and it is quite possible that, of these two closely related species, one is more readily moved to fear or wrath than the other.
Exactly at what hour E. bombijormis was seen carrying pollen is not stated, but it is to be supposed from the following that it was in the afternoon. Referring to the greater ease with which pollen- laden bees find the entrance, Grossbeck remarks "There was no uncertainty displayed as in the morning hours." This is strikingly different from the habit of E. juscojubatus, which was to collect pollen only in the early morning.
It seems likely that the reason why pollen-laden bees fly so di- rectly to their burrows is that, in the course of frequent trips to and fro during the making of the nest, they have gained a more thorough familiarity with the surroundings. As far as I remember, this directness of flight was not confined to bees bearing pollen. On Aug. 22, Grossbeck saw bees on a roadside puddle, but was not sure whether they actually lapped up the water or not. A rather strong wind was blowing at the time, by which the insects were constantly swept across the puddle. "They seemed to fly back to the windward side when blown across, for mere sport." 1 think there can be no doubt that the bees actually do take up the water, because of the regularity of their visits to the pond or puddle, the time that they spend there and the quantity of fluid coming from the mouth, used to moisten the earth and form pe11ets.l 1 F. Knab reports seeing E. bombiformis at the edge of a marsh on the outskirts of Wash- ington, alighting on the surface of the water. They remained usually about 10 sec., the proboscis in contact with the water.-Proc. Wash. Ent. SOC., 1911, p. 170.



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