egg-shaped body less than 1 inch long and about Vz 

 of an inch wide. It loops through the water sweeping 

 two long tentacles, which can extend twenty times 

 the length of the body or can be completely with- 

 drawn into the two pouches from which they emerge. 

 Each tentacle is fringed along one edge with short, 

 sticky side branches that adhere to floating fish eggs, 

 copepods, crab and oyster larvae, arrow worms, and 

 tiny fishes. As the prey is caught the tentacle shortens 

 and wipes the food off onto the rim of the narrow 

 mouth, where beating cilia on the lips carry it swiftly 

 inward to await its turn in the digestive sac — perhaps 

 already crammed full with undigested little fishes. 



During winter storms this comb jelly is driven 

 southward along the eastern coast of America and 

 can be seen in the waters of Long Island and New 

 Jersey, but in early summer it is most abundant ofl: 

 southern New England, trailing orange-tinged tenta- 

 cles. As the water warms it vanishes there and ap- 

 pears in great swarms, one individual almost touch- 

 ing another, over wide areas oflF Maine and Nova 

 Scotia, the Arctic Sea, and northern Europe. Another 

 species, P. hninnea. with purplish touches on the ten- 

 tacles, abounds otT the New Jersey coast in the fall. 

 The little ovate spheres are also well known in the 

 Pacific and the Antarctic. From San Diego north- 

 ward along the whole of the Pacific coast the beaches 

 are strewn with stranded P. hachei: but to see these 

 little sea gooseberries maneuvering about in the wa- 

 ter, with red-tinged tentacles sweeping every inch, 

 there are few places that compare with Puget Sound, 

 an arm of the Pacific Ocean that extends into north- 

 western Washington, offering protection to a great 

 profusion of invertebrates. 



A common "sea walnut" is Mertensia ovum, about 

 2 inches long and with the mouth at the more pointed 

 end of the somewhat flattened but egg-shaped body. 

 A delicate pink color tinges sense organ, tentacles, 

 and comb rows. Though Mertensia can in winter 

 wander as far southward as New Jersey, its south- 

 ward extension in summer is Massachusetts Bay, for 

 it cannot tolerate warm water. Great summer swarms 

 are seen off Maine, but the center of distribution 

 seems to be the Labrador coast, where it has been 

 seen to feed on little sculpins. On the contrary, Hor- 

 iniphoni phimosa, a warm-water species of the Med- 

 iterranean and tropical Atlantic, is seen north of its 

 normal habitat only as the warm flow of the Gulf 

 Stream carries it up the American coast or to English 

 waters. Species of Honniphora and Mertensia occur 

 also on the American Pacific coast. 



THE LOBED COMB JELLIES 



The lobed comb jellies have compressed bodies 

 drawn out on two sides into large lobes. After starting 

 in life as cydippid larvae that look like tiny sea goose- 

 berries with two long tentacles, they transform into 



The lobed comb jelly, Mnemiopsis, common along 

 the American Atlantic coast, may be seen in great 

 swarms in snmmer. When distnrbed, as by the pass- 

 ing of a boat, it glo«s brightly along the eight rows 

 of swimming plates. Large specimens are 4 inches 

 long. (Massachusetts. George G. Lower) 



adults without tentacle pouches and with tentacles 

 reduced to short filaments and fringes close to the 

 mouth. They can snare fishes longer than themselves, 

 holding them fast with the short but powerful tenta- 

 cles and closing them in, by means of the lobes, until 

 they are safely inside the mouth. Usually they satisfy 

 their voracious appetites on crustaceans and larvae 

 small enough to be entangled in mucus and wafted 

 into the mouth by ciliated grooves. Mneiniopsis leidyi 

 is pear-shaped, slightly translucent, and up to 4 

 inches long. It feeds mostly on copepods and mollusk 

 larvae, and when it is present in numbers bodes no 

 good for the oyster industry, since it can down a hun- 

 dred or more oyster larvae at a time. The summer 

 swarms of lobed ctenophores are especially noted for 

 lighting up New England waters with a greenish light 

 of great intensity. From Cape Cod to South Carolina, 

 Mnemiopsis readily adapts to marked changes in 

 salinity and temperature. Individuals that in winter 

 invade the coastal waters of New Jersey have been 

 seen with combs continuing to beat until they finally 

 freeze fast in the ice. Another species, often greenish 



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