THE VISITORS OF THE CAPRIFOLIACEE.

JOHN H. LOVELL.

THE Caprifoliaceæ, or honeysuckle family, are remarkable for the variation in length of the corolla tube and the consequent adaptation of the flowers to a great variety of visitors. The wheel-shaped flowers of Sambucus contain no honey and are sparingly visited by flies and pollen-collecting bees; Viburnum, which has also a rotate corolla but secretes nectar, attracts a wide circle of bees, flies, beetles, and Lepidoptera; the corolla of Symphoricarpos is bell-shaped and visited chiefly by wasps; the funnel-formed flower of Linnæa is adapted to slender flies; Lonicera alpigena is a wasp flower; a part of the species of Lonicera are visited by bees in general, while others are pollinated only by bumblebees; L. caprifolium and L. periclymenum are nocturnal flowers fertilized by hawk moths; and L. sempervirens is pollinated by humming birds.

There are about 260 species widely distributed throughout the northern hemisphere and blooming in spring and midsummer. A few occur in South America and Australia. Their northern distribution, as well as the occurrence of fossil forms, indicates their origin in the north temperate zone. Viburnum is found in the Dakota group, which, according to Saporta and Marion, belonged to a woody and mountainous region, populated by such genera as Salix, Fagus, Populus, and Platanus, and from which southern types, especially the palms, are absent.

SAMBUCUS L.

The flowers attract very few visitors, as they contain no nectar.

Sambucus pubens Michx. Red-berried Elder.

The flower buds are at first green, changing to purplish, and finally, on expanding, to white. Cymes thyrsoid, longer than broad.

Visitors Hymenoptera - Apidæ : (1) Apis mellifica L., ?; Andrenidæ (2) Andrena vicina Sm., ?.

Diptera

Syrphida: (3) Syrphus ribesii L.

Coleoptera Cerambycidae: (4) Pachyta monticola Rand; Mordellidæ : (5) Anaspis rufa Say. Waldoboro, May 19 to June.

Sambucus canadensis L. American Elder.

The broad, flat cymes are very numerous and conspicuous. The flowers attract very few visitors, as they contain no honey and bloom at midsummer, when they come in competition with many nectariferous blossoms. Only four species of flies have been collected, and repeatedly the blossoms were examined without observing a single visitor, and yet upon the jewel-weed (Impatiens) and the red-osier cornel, a few yards away, scores were at work. The perfume is agreeable and increases in the evening, but fails to attract crepuscular insects. The stamens are slender, surpassing the nearly sessile stigmas.

Visitors Diptera - Syrphida: (1) Mesogramma marginata Say; Sarcophagidae: (2) Helocobia helicis Town.; Muscidæ : (3) Lucilia cornicina Fab.; Anthomyidæ : (4) Phorbia fusciceps Zett. Waldoboro, July.

Sambucus nigra L. Black Elder.

A variety of this species, S. nigra laciniata (Mill.) DC., has escaped from cultivation at Cape May, N. J. According to Knuth, the flowers of S. nigra are yellowish-white, honeyless, and conspicuousness is gained by their aggregation in a dense corymb. There are few visitors, partly because the strong scent is probably repellent to bees, and partly because of the absence of nectar. In the Island of Föhr, Knuth collected two flies feeding upon the pollen, and in Helgoland a single fly, Lucilia cæsar. In middle and southern Germany, Müller observed six flies, two beetles, and one sawfly.

VIBURNUM L.

There are fourteen species in the Northern States. The flowers are in compound cymes, which bloom in early spring or midsummer, and are white, fragrant, and nectariferous.

Viburnum alnifolium Marsh. Hobble Bush.

The inflorescence is in broad, flat corymbs of flowers of two different sizes. The center florets are small, 5 mm. broad, white tinged with red, and in autumn produce bright-red berries; while the marginal ones, a single row of which surrounds the corymb, are large, 20 mm. broad, white, and sterile. Their size has been increased at the expense of their fruitfulness, and as their use is to attract the attention of insects, they open a day or two in advance of the inner and smaller florets. "The older flowers are actually occupied," Kerner remarks, "in the allurement of insects for the advantage of the younger ones." Since their conspicuousness is useless to themselves but of benefit to the community, they may be said unconsciously to play the part of benefactors. The stamens stand nearly erect, and spontaneous self-fertilization can easily occur by the pollen falling upon the sessile stigmas.

Visitors Hymenoptera - Apidæ : (1) Apis mellifica L., ĕ; (2) Bombus bifarius Cr., ; (3) Nomada maculata Cr., ;, Andrenida (4) Andrena sp.; (5) A. sp.

Diptera Syrphida: (6) Syrphus ribesii L.; (7) Brachypalpus marginatus Hunter; Muscidæ: (8) Myiospila meditabunda F.; Cordyluridæ : (9) Scatophaga stercoraria L.

Coleoptera Elaterida (10) Elater rubricus Say; (11) Megapenthes rogersii Horn1; Cerambycidæ : (12) Cyrtophorus verrucosus Oliv.; (13) Microclytus gazellula Hald.; Edermeridæ (14) Asclera ruficollis Say; Mordellidæ : (15) Anaspis rufa Say; also Pachyta monticola Rand.

Hemiptera - two species. Waldoboro, May 9–19.

Viburnum lentago L. Sweet Viburnum. ·

The flowers are homogamous. The stamens are much longer than the stigmas and divergent; self-fertilization is not, how

1 In his list of Coleoptera from the southern shore of Lake Superior, 1896, Prof. H. F. Wickham remarks: “Of the Elateridæ it is a pleasure to record the capture of a fine specimen of Megapenthes rogersii, a rare insect recorded hitherto only from Canada.” The specimen taken by the writer was determined by Professor Wickham.

ever, impossible, as the inflorescence often stands in such a position that the stigma is directly in line with the falling pollen. The large size of the cymes and their great abundance render the bush very conspicuous. The odor is faint but agreeable. Honey is secreted in a thin adherent layer by the ovary, but may be observed more readily in the angle formed with the corolla, where it is sought by insects.

Visitors: Hymenoptera — Apida: (1) Apis mellifica L., §, common; Andrenidæ : (2) Halictus disparalis Cr., ; (3) Andrena vicina Sm., ?, common; (4) A. rugosa Rob., ?; (5) A. designata Ashm., ; (6) A. viola Rob., ; (7) A. claytonia Rob., D.

Diptera - Syrphidae: (8) Eristalis transversus Wied.; (9) E. saxorum Wied.; (10) Syrphus ribesiï L.; (11) Sphærophoria cylindrica Say; (12) Mellota postica Fab.; (13) Helophilus latifrons Loew; (14) Syritta pipiens L.; Empididæ: (15) Rhamphomyia luteiventris Loew; Muscidae: (16) Morellia micans Macq.; also minute Diptera.

Coleoptera-Nitidulida: (17) Carpophilus brachypterus Say; (18) Colastus truncatus Rand; Cerambycidæ (19) Leptura lineola Say; Scarabæida: (20) Hoplia trifasciata Say; Mordellidæ: (21) Anaspis rufa Say. Waldoboro, June 16, 17, 18, and 21.

Viburnum dentatum L. Arrowwood.

Honey is secreted by the lower part of the ovary, and there is a faint, rather peculiar fragrance. The stamens are 5 mm. in length and much surpass the stigmas. The flowers are not so frequently visited by insects as V. lentago. In addition to the list given below, two butterflies were seen at a distance upon the inflorescence.

Visitors: Hymenoptera — Andrenidæ : (1) Halictus sp.; (2) Andrena rugosa Rob., 9.

Diptera Syrphidæ : (3) Syrphus ribesii L.; (4) Chilosia sp. Coleoptera Elaterida: (5) Elater rubricus Say; (6) Sericosomus incongruus Lec.; Cerambycidae: (7) Leptura chrysocoma Kirby; (8) L. vittata Germ.; (9) L. lineola Say; Scara

bæidæ (10) Hoplia trifasciata Say; (11) Macrodactylus subspinosus Fab. Hemiptera

one species. Waldoboro, July 6-10.

Viburnum cassinoides L. Withe Rod.

The structure of the flowers is very similar to that of the preceding species. The perfume is distinct, and the flowers contain honey.

Visitors: Hymenoptera - Andrenidæ: (1) Andrena vicina Sm., ; (2) Halictus palustris Rob., ?.

Lepidoptera - Rhopalocera: (3) Lycana pseudargiolus Boisd. & Lec.

Diptera Syrphida: (4) Sphærophoria cylindrica Say; (5) Syrphus ribesii L.; Empididæ: (6) Empis pubescens Loew; (7) Rhamphomyia luteiventris Loew; Sapromyzidæ: (8) Sapromyza longipennis Fab.

Coleoptera Elaterida (9) Agriotes stabilis Lec.; (10) A. fucosus Lec.; Lampyridæ : (11) Telephorus fraxini Say; Cerambycidae (12) Leptura mutabilis Newm.; (13) Pachyta monticola Rand; (14) Molorchus bimaculatus Say; Cistellida: (15) Isomira quadristriata Coup. Waldoboro, June 26–28.

In V. pubescens Pursh and V. prunifolium L. the flowers are homogamous, and spontaneous self-fertilization and geitonogamy may occur. (Robertson, Bot. Gaz., Vol. XXV, No. 4.)

An examination of the table shows that the most important visitors are Andrenidæ, flies, and beetles, to which the inflo