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Incipient nest of Bombus terrestris, showing honey-pot and mass of wax enclosing young brood and grooved for the accommodation of the body of the queen while incubating. After F. W. L. Sladen.

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Same as Fig. 43, showing the queen Bombus terrestris lying in the groove and incubating the young brood. After F. W. L. Sladen.

so that they seem welded into a compact mass. They do not, however, form a flat-topped cluster, but the cocoons at the sides are higher than those in the middle, so that a groove is formed; this groove is curved downwards at its ends (Fig. 43), and in it the queen sits, pressing her body close to the cocoons and stretching her abdomen to about double its usual length so that it will cover as many cocoons as possible; at the same time her outstretched legs clasp the raised cocoons at the sides (Fig. 44). In this attitude she now spends most of her time, sometimes remaining for halfan-hour or more almost motionless save for the rhythmic expansion and contraction of her enormously distended abdomen, for nothing is now needed but continual warmth to bring out her first brood of workers. In every nest that I have examined the direction of the groove is from the entrance or honey-pot to the back of the nest, never from side to side. By means of this arrangement the queen, sitting in her groove facing the honey-pot-this seems to be her favorite position, though sometimes she reverses it-is able to sip her honey without turning her body, and at the same time she is in an excellent position for guarding the entrance from intruders."

The eggs laid by the queen during the early part of the summer are fertilized and therefore produce females, but the larvæ, owing to the peculiar way they are reared, secure unequal quantities of nutriment and therefore vary considerably in size, though

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Comb of Bombus lapidarius, showing clusters of worker cocoons, masses of enclosed larvæ, half-full honey-pots and pollen pot. After F. W. L. Sladen.

they are all smaller than their mother. Individuals scarcely larger than house-flies are sometimes produced, especially in very young colonies. All of these individuals have been called workers, although they have essentially the same structure as the queen. They are assisted in emerging from their cocoons by their mother or sisters and forthwith take up the work of collecting pollen and nectar and of enlarging the colony. The queen now remains in the nest and devotes herself to laying eggs, while the nest is protected, new cells are built and the additional broods of larvæ are fed by the workers. They also construct honey-pots and special receptacles for pollen or store these substances in cocoons from which workers have emerged (Fig. 45). Later eggs are also laid by the workers but being unfertilized develop into males. As the colony grows and becomes more prosperous, some of the larvæ derived from fertilized eggs laid by the queen are abundantly fed and develop into queens. Like the queens of the social wasps, these do not emerge from their cocoons till the late summer, and like the queen wasps, they disperse, after mating with the males, and alone of all the colony survive the winter to start new colonies the following spring. In South America, where, according to von Ihering, bumble-bee colonies are perennial, new nests are formed by swarming as among the social wasps of the same region. Bumble-bee colonies are, as a rule, not very populous, 500 individuals constituting an unusually large society. In many cases there are scarcely more than 100 to 200.

I have called attention to the fact that the workers are precisely like the queens, or fertile females, except that they have been more or less inadequately fed during their larval stages and are therefore smaller. They are the result of a high reproductive activity on the part of the queen under unfavorable trophic conditions that do not permit the offspring to attain their full stature. In certain species that live permanently under even more unfavorable conditions, like those in the arctic regions, the worker caste is completely or almost completely suppressed. During 20 years of residence in Tromsö, Norway, Sparre Schneider failed to find a single worker of Bombus kirbyellus, and those of B. hyperboreus were extremely rare. Probably the queens of these species are able to rear only a few offspring and these are all or nearly all males and queens, though, during the short arctic summer, at least in Finland and Lapland, the mother insects work late into the nights. But the worker caste may also disappear as a result of the opposite conditions, that is, an abundance of food. We found this to be the case with the workerless parasitic wasps, Vespa arctica and austriaca. In north temperate regions the genus Bombus has given rise to a

number of parasitic species, which have been included in a separate genus, Psithyrus. These bees are very much like Bombus, in the nests of which they live, but just as in the two species of Vespa and for the same reasons, their worker caste has been suppressed.

The foregoing account shows that the bumble-bees are very primitive and represent an interesting transition from the solitary to the social forms, since the queen while establishing her colony behaves at first like a solitary bee but later gradually passes over to a stage of progressive provisioning and affiliation of her offspring and thus forms a true society. The cells are also essentially like those of solitary bees, except that they are made of wax, but even in the secretion of the wax the bumble-bees represent the primitive conditions, as compared with the stingless bees and honey-bees, since the substance is exuded between both the dorsal and ventral segments of the abdomen.

THE POLYNESIANS: CAUCASIANS OF THE

PACIFIC

By CLIFFORD E. GATES

COLGATE UNIVERSITY

N the oceanic islands of the Pacific three different peoples occur,

IN

who have been called Melanesians, Micronesians and Polynesians. These form very distinct divisions. The Melanesians are physically negroid, nearly black with crisp, curly hair, flat noses and thick lips. Although nothing is known of their origin, it is supposed that they came from Africa and were the earliest occupants of the oceanic world. They now occupy the western portion of the Pacific islands south of the equator including Fiji, the New Hebrides, the Solomon group and the Bismarck Archipelago.

The Micronesians are of Malay stock much modified by Melanesian, Micronesian and even Chinese and Japanese crossings. They are short, often stunted in form, and have a dark brown complexion. They inhabit the western portion of the Pacific islands north of the equator, including the Marshall Islands, the Gilbert Islands, the Caroline Islands and Guam.

The Polynesians represent a branch of the Caucasian race who migrated in a remote period, possibly in the Neolithic age, from the Asiatic mainland. They have a distinct European cast of feature, have a light brown or olive complexion, and are the physical superiors even of Europeans. They inhabit all the eastern group of islands both north and south of the equator, including the Hawaiian, Marquesan, Society, Cook, Tonga and Samoan Islands.

The Micronesians, few in number and inhabiting a relatively small area of Oceanica, have been of little interest to other peoples; the Melanesians, black and savage, with a history of horror after horror, have been repellent to explorers and remain in a darkness comparable to the darkness of central Africa. But the Polynesians have cast a charm over the civilized world. They are perhaps the handsomest people extant. The men average six feet in height, are strongly muscled, free from fat, swift in action, graceful in repose; the women are often of rare beauty, with regular features and wondrous large, dark eyes. In character they are exceedingly merry, gentle, courteous and hospitable. Unless mistreated or under some misapprehension they have been almost universally friendly

VOL. XV.-17.

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