. Cassell's natural history. Animals; Animal behavior. TUE has a large quantity of carbonate of lime in its stem, and it is interesting to note tlie repetition of external form, in tliis division, of that noticed amongst the corneous-stemmed forms. It is the genus Gorgonella, and it corresponds to the Leptogorgias in the last division, but tlie axis is very calcareous, and Verucella has the configuration of the Gorgonias. One genus, Juncella, lias- a simple, non-branching, straight stem, like a stick, and the polypes project slightly. It has been found in the Mediterranean, off Bah
. Cassell's natural history. Animals; Animal behavior. TUE has a large quantity of carbonate of lime in its stem, and it is interesting to note tlie repetition of external form, in tliis division, of that noticed amongst the corneous-stemmed forms. It is the genus Gorgonella, and it corresponds to the Leptogorgias in the last division, but tlie axis is very calcareous, and Verucella has the configuration of the Gorgonias. One genus, Juncella, lias- a simple, non-branching, straight stem, like a stick, and the polypes project slightly. It has been found in the Mediterranean, off Bahia, and On the east coast of Africa. The last group is that of the Briaracece, in which the axis, or stem, is no longer dense, solid, and concentric, but may be hollow or a mere mass of spicules. Briareum is the typical genus, and Paragorgia is its most important ally. THE FAMILY With the exception of one genus, this great family is characterised by the absence of anything, like a continuous skeleton or supporting dense hard structure. In no case is there an axis, as in the Red Coral and Gorgonias, but there is much soft structure, in which isolated caloareous sclerites or spicules are placed, sufficient to detract from a perfect con- tractility and softness. Hence some are leathery or fleshy. The polypes are fashioned after the Alcyonarian type, have eight pinnate tentacles, and their visceral cavity has membranes in it sup- porting the reproductive elements. The soft tissues, or coenosarc, contain the polypes, whose centres communicate with a common series of minute canals. Many forms increase by budding, some from the base and others from the sides, and thus two sub-families, the Cornularinse and the Alcyonina?, can be established. There are some forms, however, which pro- duce a wall of calcareous spicules- and a kind of corallum, and thus- a third sub-family, the Tulii- porinse, is formed. This is a verjr exceptional form, and the rest ire fixed by their fleshy
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Keywords: ., bookcentury1800, bookdecade1890, booksubjecta, booksubjectanimals
