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sections more or less distinct, and terminated by two long filiform 

 tentacles issuing from the base of the zoophyte and fringed on the 

 sides. " It is," says Gosse, " a globe of pure colourless jelly, about as 

 big as a small marble, often with a wart-like swelling at one of its 

 poles, where the mouth is placed. At the other end there are minute 

 orifices, and between the two passes the stomach, which is flat or wider 

 in one diameter than the other." Cydippe pileus, found abundantly 

 in the spring on the Belgian coast, is so transparent that it is 

 scarcely visible in the water, where it seems like living, moving 

 crystal. C. densa, which abounds in the Mediterranean, is of a 

 crystalline white, with rows of reddish cirrhi, terminating in two 

 tentacles, much longer and coloured red; it is about the size of a 

 hazel-nut, and phosphorescent. Within the clear substance of the 

 Cydippe, on each side of the stomach, there is a capacious cavity, 

 which communicates with the surface, and within each cavity is fixed 

 the tentacle, of great length and very slender, which the animal can 

 at pleasure shoot out of the orifice and suffer to trail through the 

 water, shortening, lengthening, twisting, twining, or contracting it into 

 a tiny ball at will, or withdrawing it into its cavity, short filaments 

 being given off at intervals over the whole length of this attenuated 

 white thread-like apparatus, each of which can also be lengthened 

 or shortened, and coiled individually. These proceed only from one 

 side of the thread-like tentacle, although, at a casual glance, they seem 

 to proceed now from one side, now from the other. 



CALLIANIEA. 



The Callianira form a sort of connecting link between the Beroes 

 and the Cestidse. Their bodies are smooth and regular, vertically- 

 elongated, compressed on one side and as if lobated on the other ; in 

 substance they are gelatinous, hyalin, and tubular, obtuse at both 

 extremities, with buccal openings between the prolongations of the 

 side, and two pair of conical appendages resembling wings, capable 

 of expansion, on the edges of which two rows of vibratory cilia are 

 ranged. A great transversal opening presents itself at one of the 

 extremities, a small one at the other. The animal is furnished with 

 two branching tentacles, but without cilia. 



