Part 19

This particular British sea worm, Amphitrite ventilabrum, is almost as notable for the beauty of its blossom as for its masonry. Each of the tentacles has about a thousand of the petal-like processes and each of these, it is claimed, is capable of some degree of independent action. “It is no exaggeration to affirm,” wrote the eighteenth-century British biologist Sir John Dalyell, “that the will of this lowly, defenseless creature is fulfilled by control of at least twenty thousand living parts.”

The color of the petals is basically straw-yellow, dotted and banded with brown, rouge, red, and green. “While dredging in the river Roach,” Dalyell reported, “I have come upon banks where these worms existed in hundreds of thousands and appear in masses of large extent growing erect like standing fields of corn.”

Of another British tube builder which builds tubes of cemented shells or pebbles near the roots of large sea weeds, Rev. Richard Johnston says: “Sabellarid angilica is a timid, lively, active creature whose most prominent ability is that of constructing a dwelling for itself from sand grains. It is firm, durable, and capable of great resistance. They are not easily crushed. Some appear much more brittle. Most of the dwellings are lined with a soft, silky substance formed of exudations from the body. The worms have a great preference in building materials. They always prefer sand or shells. Powdered glass is used reluctantly and soon rejected. Some tubes are short and confined, others considerably prolonged so as to afford safe retreats in danger. Some architects seem to persist in prolonging the fabric as long as material can be found. They never weary of working. Grains of sand are selected and adopted for precise spots and gelatinous matter secures them in the tube walls.”

Perhaps the most notable of all the worm builders is a five-inch-long species found in South African waters, pectinaris capensis, described by Sir John McIntosh: “The beautiful straight tube formed by this animal was composed of the spicules of sponges in short lengths placed traversely and fixed by secretion so as to form a perfectly round tunnel gently tapered from the wide to the narrow end. The spicules appeared of the same size throughout the tube. The inner surface was as smoothly formed as the outer. The labor involved in selecting and fitting with such marvelous skill the sponge spicules composing so large a tube must have been very arduous. One tube lasts the animal for life.”

McIntosh tells of another South African architect worm that “builds out of grains of sand arranged in a single layer like miniature masonry and bound together by waterproof cement.”

There are, however, widely differing degrees of artistry among the tube-dwelling polychaetes. Some tubes are rough, fragile, long, bent in various directions, and united in colonies several inches to a foot across. Sometimes tubes three to four inches long are attached horizontally to the undersides of rocks.

A large and singular terebellid is Amphitrite ornata—twelve to fifteen inches long with orange-brown tentacles capable of being extended eight to ten inches. These are kept in constant motion gathering food and material for building. The bodies of these worms are filled with blood, but there is no circulatory system. The blood, however, apparently can be forced into any part of the body by muscular contractions. The tentacles can be turned voluntarily in any direction by forcing blood into them.

Tube-building, flowering worms excited the wonder of Quatrefages as he observed them along the Bay of Biscay in the nineteenth century:

“On these coasts so violently beaten by waves we often observe small hillocks of sand pierced by an infinite number of minute openings. These little hillocks which look very much like thick pieces of honeycomb are in reality populous cities in which live in modest seclusion tubiculous annelids, the hermellas—(sabellarids) as curious as any that fall under the notice of the naturalist. The body, about two inches in length, is terminated in front by a bifurcated [two-forked] head bearing a bright double golden crown of strong, sharp silk threads. These brilliant crowns are not mere ornaments, but are the two sides of a solid door, or rather true portcullis, which hermetically closes the entrance to the habitation when, at the least alarm, the worm darts with the rapidity of lightning within its house of sand.

“From the edges of the head of this worm issue fifty to sixty slender, light-violet filaments which are incessantly moving about like numerous minute serpents. They are so many arms which can be lengthened or shortened at will and which, seizing the prey as it passes, bring it to the hollow, funnel-shaped mouth. On the sides of the body appear little projections from which issue bundles of sharp and cutting lances. Finally, the back is covered with cirrhi, recurved like circles, whose color varies from dark red to deep green.”

Most conspicuously flowerlike among the worms are the serpulids—“little snakes.”

Found the world over, they furnish passable imitations of practically all the flowers in an old-fashioned Virginia garden. Among them, for example, are the animals of inshore South African waters, described by Prof. McIntosh. Their wreaths of branchia “look like pinks, but in some varieties are purple at the base, with narrow bands of bright red and pale green. In one variety the blossoms are yellow or orange and the body is usually greenish-yellow.” “The instant it is disturbed,” McIntosh says, “this worm withdraws its lovely wreath into its tube and closes the aperture with a curious plug, funnel-shaped and placed at the end of a rather long pedicle.”

The Rev. D. Johnston describes a British flower worm (one of the sabellids) about an inch long, whose eight-inch-long tubes grow together, attached at the bottom to a stone or abandoned shell. The tube has a silk-like lining.

“Into this tube,” says Johnston, “it can withdraw with lightning-like rapidity when alarmed. Extending across its back is a row of microscopic hooks, or 14,000 to 15,000 teeth. These are used to catch the lining of the tube and draw the worm back.”

The filaments which form its blossoms, he says, are comb-like, arranged in two rows, one on each side of the mouth. They form a coronet. Under low magnification each is seen as a pellucid, cartilaginous stem from one side of which springs a double series of secondary filaments through which red blood can be seen flowing.

Some of the most conspicuous flower worms are found alone: the Atlantic coast of the United States. On diving into Chesapeake Bay one encounters tiny, colored clusters of feathers that are really gills of annelid worms. They flick instantly out of sight as their owners withdraw into tubes in the rock crevices. The blossoms are bright orange, each surrounded by a white haze caused by thousands of minute tentacles straining the water for the tiny organisms upon which they feed.

From New Jersey to Cape Cod is to be found a purple-blooming serpulid with white stems of calcium carbonate three to four inches long and an eighth of an inch in diameter.

A widely distributed family related to the serpulids are the fabricinae, or “feather dusters.” These animals, only a few millimeters long, live in the upper layers of mud in tidal basins. They are so thoroughly covered with slime and debris that they are likely to be completely overlooked. The body is thread-like except for the crown of tentacles, with from seventy to a hundred featherlike filaments. In some varieties these are white, in others translucent.

The Heavy Toll of Bird Migrations

A migration that takes a toll of millions of lives takes place every year between North and South America.

Dr. Alexander Wetmore of the Smithsonian has had the experience of standing on a lonely beach on the coast of Venezuela and actually watching North American birds arrive at the end of their gruelling journey, exhausted and emaciated. Every day over his camp on the shore passed familiar birds from home—sandpipers, yellowlegs, bobolinks, barn swallows and warblers.

“There was brought to me more definitely than ever before,” Dr. Wetmore reported, “the tremendous loss of life that this journey entails. The wastage of modern human battlefields, though terrific beyond words, is nothing in comparison. On this open shore small feathered migrants often made a landfall in a state of evident exhaustion. In the early morning I found little groups of them feeding on the short herbage. Some obviously had barely made a landfall after an exhausting sea journey. In some of those that I handled the flight muscles that move the wings were reduced to thin bands through which the angular ridges of the breast bones protruded. It was easy to visualize the hundreds of thousands that had wandered over the water until they fell to drown, and the hundreds of others that arrived only to succumb to the strains imposed by their exhausting journey.”

Deadly Snakes That Take Life Easy

Deadliest of serpents are the Pacific sea snakes. A bite almost certainly would be fatal to a human being. Yet native children of the Palau Islands in the South Pacific play with these reptiles with complete impunity. They pick them up and toss them from one to another just as American children play “catch.” Natives of the Palaus look upon the reptiles with complete indifference.

The term “sea snake” is somewhat of a misnomer. Actually the creatures spend most of their days asleep among rocks on beaches. They are excellent tree climbers and like to sun themselves in crotches of branches. At dusk, however, they move out to the reefs where presumably they spend most of the night pursuing small fishes, their principal food. They are excellent swimmers and their bodies have been somewhat modified, with flattened, paddle-like tails, for sea life.

Fortunately, on land at least, they are sluggish and non-aggressive. They hardly can be induced to bite and will suffer almost any indignity without retaliating. About the only way a person would be likely to be bitten would be by stepping directly on the head of one of these snakes with bare feet. This is an unlikely event, for the sea snakes do not spend any time under shallow water where they would be a peril for bathers.

Some are quite beautiful, about five feet long and banded with black and white. Their capture is easy. It is simply a matter of pinning down the head with a stick and picking up the snake by the neck.

Throughout the entire sea snake area in the Pacific there are only five or six instances reported where the serpents have bitten humans. In every case the victim has died; there is no anti-venom against the sea snake toxin.