THE CTENOPHORJE. 



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noticed that sometimes one-half of their flappers were acting, whilst those of the other side of the body 

 were at rest, thus producing rotary motion. 



The combs, which are very small, are placed on horizontal bands of muscular tissue, and when 

 they move by day they are iridescent and very beautiful. 



One of the most beautiful of the Otenopborse belonging to the globular sub-order is the type of 

 the family Cydippidse, and is a species of Pleurobrachia.* It is a small transparent sphere, occasionally 

 becoming bulged out, and there is a slit-like mouth on the top, and a dark eye-spot is at the other 

 pole. Eight rows of fringes run, like lines of longitude, from pole to pole, dividing the surface, like the 

 ribs on a melon. Hanging from either side of the body, from just above the eye-speck, are two 

 very long tentacles, like soft fringes of feathers on a spring. They are in rapid movement when 

 necessary, coiling, undulating, and moving the little body in most graceful curves, or they may stream 

 out listlessly, and float behind, a foot or eighteen inches in length. In an instant they may contract, 

 and fold into a knot not larger than a pin's head. The prevailing tint of the little sphere is given by 

 the motions of these wonderful fringes, and it may be yellowish, pink, green, red, and purple. These arise 

 from small sacs, into which they may be withdrawn. The mouth is brought constantly within i-each 

 of its minute prey small immature marine animals and plants by the motion of the fringes, and the 

 food passes down a wide digestive cavity between two tubes. These unite at the lower part of the 

 body in a single funnel-shaped cavity, which is a reservoir for the circulating fluid poured through 

 an opening in the digestive cavity into it. The food and much water pass into this canal and are sent 

 ramifying through a series of tubes about the body. These chymiferous tubes start horizontally and 

 at right angles to the digestive cavity, from the point of junction of the vertical tubes and the canal. 

 When they reach the periphery, 

 each one joins a longitudinal 

 tube which is just within one 

 of the rows of flappers, and 

 more or less connected with it. 

 The Atlantic, and the northern 

 parts especially, are favourite 

 localities of this genus, but 

 others of the family are found 

 in the Mediterranean and the 

 Pacific Ocean. 



The pretty Beroe and the 

 genus Rangia belong to the 

 sub-order Eurystoma, and their 

 oval bodies are contractile, and 

 without lobes and tentacular 

 filaments of much length. The 

 mouth and stomach are large. 



Some of the Ctenophorre, 

 such as the Bolinse, are lobed 

 in the region of the mouth, 

 which is downwards, and the 

 body departs from the globular 

 shape and does not have long 

 tentacles. They move with a 



sluggish, slow, and undulating movement, and have the eight rows of small paddles, but they 

 differ in length according to their position on the body. The motion is assisted by appendages, called 

 auricles of the lobes ; and the whole animal, according to Agassiz, resembles a white flower with the 

 crown expanded, and especially when it reverses itself and floats mouth upwards. The genus is found 

 in the Northern Seas. 



The family Cestidse belongs to the ribbon-shaped order ; and Cestum veneris (Venus' Girdle) of the 



* Pleurobrachia rhododactyla. 



VENUS' GIRDLE (Cestum veneris). 



