Page:Popular Science Monthly Volume 44.djvu/468

454 thus captured, was taken directly to the laboratory and examined. By dipping out small portions in glass dishes and holding them up to the light we could detect a great number of minute pelagic animals swimming about in great commotion. These "surface collections" are intensely interesting, for in them the biologist finds multitudes of embryonic forms in various stages of their development. The larvæ of starfish, sea urchins, shrimps, conchs, and other forms, appear in their normal living state under his lens. Besides larvæ, numerous adult forms, as Sagitta, Appendicularia, platoid worms, Medusæ, and green Algæ, are collected. A careful survey of the hosts of forms thus captured, and a fair understanding of their true significance, prepare one for the often-repeated statement that "the ocean is the original home of all life." We are impressed with the fact that it is from this source that we must seek further information that shall throw light upon many biological problems at present unsolved. A few days of general collecting in the sea suffices to reveal the great abundance of life in the ocean as compared with its scarcity on land.

The various expeditions taken by our party in the tropics would have been interesting and enjoyable to almost any one. To the casual observer they may have presented the appearance of pleasure excursions, rather than trips for earnest work and study.

On one occasion we sailed to Salt Pond, a kind of lagoon bordering the sea, where numbers of crocodile and turtle were frequently found. We had been rowing about for some time in the pond with no success except that of catching mullet with a throw-net, and taking note of the numerous cranes, pelicans, and bitterns flying about, when we came upon a "crocodile slide." This is a smooth, broad trail leading up the bank, which the beast follows when it wishes to prepare a nest in the sand for its eggs, or take a ramble beneath the underbrush.

No sooner had we neared the slide than here came a frightened crocodile about seven feet in length, dragging himself down the slippery bank into the water. As it swam out in front of our boat, its black nose protruded above the surface, offering a fine shot, but fortunately for the crocodile our gun was left at home.

Before leaving the pond we secured a fine collection of large, beautiful jellyfish (Cassiopea), and luckily for us the boatman discovered a dozen or more little crocodiles among the mangrove roots; we all repaired to the scene, and amid much excitement succeeded finally in capturing one.

One of the most productive collecting fields for our studies was that in the mangrove ponds off the "pallisadoes," near Port Royal. The mangroves in this region have extended into the shoal water,