have dark pigments in the cells also. A horny central 

 axis usually adds mechanical support. This group is 

 noted for its bright luminescence, usually blue or vio- 

 let, sometimes greenish or yellowish. The slime se- 

 creted by pennatulids contains luminescent granules; 

 the dried slime will glow when water is added, but it 

 cannot be stimulated in other ways. The intact ani- 

 mal, or pieces of a colony, luminesce only on stimu- 

 lation. In the more primitive forms, like Veretilluni. 

 common in the coastal muds of the Mediterranean 

 and also found in the Altantic, the upper part of the 

 body is a stout fleshy club with flowerlike polyps 

 strewn over the surface in no obvious order (Plate 

 10). More like a quill pen is Peiuuiiiila pliosphorea, 

 which lives somewhat farther from shore but often 

 comes up in fishermen's nets. The stalk is yellow- 

 orange, and the expanded upper part, which bears 

 rows of polyps on each side as a feather bears its 

 barbs, is purple. The polyps glow a bluish green, 

 and when they are stimulated repeatedly, waves of 

 light run the length of the region bearing the polyps. 

 After this response the colony contracts and expels 

 water. In the same Mediterranean and Atlantic hab- 

 itats as Pennatida, and as far north as Norway, dredg- 

 ing brings up the related wandlike Virgularia, with a 

 slender body up to 2 feet long and polyps closely 

 packed in rows on either side at interv-als along the 

 stem. Pink, rose-colored, red, and purplish red va- 

 rieties of Pennatida are widely distributed along 

 the New England coast, growing more abundant as 

 dredging proceeds to deeper and deeper water, even 

 to six thousand feet. One species may be only 4 

 inches long, but the other, the great sea pen, well 

 known to halibut fishermen, attains a length of 20 

 inches. Also present in these deeper waters are sev- 

 eral tall wandlike forms related to Virgularia. They 

 grow 3 feet high and may bend from the weight of 

 sea anemones that live on the long basal stalk. On 

 the American Pacific coast, in the mud of shallow 

 bays from San Francisco to San Diego, are two com- 

 mon sea pens: Stylatida is rough to the touch and 

 about 1 foot long; Acanthopiilum is smooth to the 

 touch and up to 2 feet long. In Between Pacific Tides, 

 Ricketts and Calvin tell of rowing in Newport Bay at 

 low tide and looking into the shallow water at a 

 pleasant meadow of waving green Stylatida pens 

 "like a field of green wheat." When they reached 

 down with an oar to unearth one, the feathery pens 

 instantly snapped down into the sandy mud, leaving 

 only their very tips to betray their presence. Entirely 

 deep-water or abyssal are pennatulid families like 

 the Umbellulidae. Vmhellida has a very slender 

 bare stem, perhaps 2 feet long, topped by a cluster 

 of large orange-red or purplish flowerlike polyps. 

 One that emitted a bluish light was hauled up from 

 about fifteen thousand feet by the ship Galathea. 

 The sea pansy, Renilla, a very different kind of 



I 



A pale orange sea pen, Leioptihis, from deeper shore 

 waters of ifie .American Pacific coast. The stalk is 

 partly imbedded in sand. Large specimens may be 

 2 feet long. (Ralph Buchsbaum) 



pennatulid, is common in the West Indies and on 

 warm American shores, extending northward to the 

 Carolinas and to southern California. Related forms 

 are known from the Red Sea and from Australian 

 and other coasts. Though named for its kidney shape 

 and violet color, it may be heart-shaped or of a rosy 

 pink tint. It lies with the short stalk buried, and the 

 flattened disklike body bears on its upper surface two 

 kinds of polyps, arranged in a regular pattern. Sea 

 pansies may occur in a muddy bay by the hundreds 

 or even by the thousands, the lovely color obscured 

 by a thin coating of sand or mud. Transferred to a 

 dish of clean sea water and left undisturbed, the disk 

 may expand to several times its contracted size and 

 the polyps may open. If they are kept in the dark for 



103 



