. The sea-beach at ebb-tide : a guide to the study of the seaweeds and the lower animal life found between tidemarks . tretch out toa remarkable length,— forty to fifty feet,—acting as anchors to keep the colony frombeing driven ashore. They also change itscourse by raising the pointed end of thefloat, thus forcing it to come about. Theselong tentacles, ordinarily carried more or lesscurled up, are in bunches of two to four, andemerge from a common stem. Clusters ofsimilar, but smaller, tentacles alternate withthe larger ones, but grow somewhat nearerthe pointed end of the float; these are pur
. The sea-beach at ebb-tide : a guide to the study of the seaweeds and the lower animal life found between tidemarks . tretch out toa remarkable length,— forty to fifty feet,—acting as anchors to keep the colony frombeing driven ashore. They also change itscourse by raising the pointed end of thefloat, thus forcing it to come about. Theselong tentacles, ordinarily carried more or lesscurled up, are in bunches of two to four, andemerge from a common stem. Clusters ofsimilar, but smaller, tentacles alternate withthe larger ones, but grow somewhat nearerthe pointed end of the float; these are purelylocomotive organs. Next come two smallersets of appendages, also of unequal size,which are the nutritive organs of the com-munity. They are clustered together on astem like the others. The appendages ofthe thiid kind are small, resemble bunchesof grapes, and are scattered among the nutritive hydra?. These lastare the reproductive zooids of the community. GENUS Vellela V. linibosft. This hydroid is abundant on the Florida coast. It hasa bright-blue, flattened, oblong, bladder-like float, four to five indies. Ihitmiliii iirilliiimi. Iortuuiiisi man-of-war, one tlltli natural M/.I-. 132 MARINE INVERTEBRATES long, which is divided into a number of concentric, communicating com-partments. The margin of the float is entire, and a triangular sailextends diagonally across the top. On the under side is a single mouthon a manubrium, and surrounding it are a large number of short thread-like appendages having different functions. Some of them are feelers,others bear reproductive buds, and others have stinging-cells. Associ-ated with Vellela is an allied hydroid called Porpita, which has no sail,and in company with these two is a jellyfish called Bataria, which issupposed to be the offspring of one or the other of them.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectmarinea, bookyear1901
