Figure 10. Common mobile invertebrates. (A) Ampithoe longimana (to 10 mm length), (B) Panopeus herbstii 

 (to 25 mm length), (C) Asterias forbesii (to 150 mm diameter), (D) Arbacia punctulata (to 50 mm diameter), and 

 (E) Urosalpinx cinerea (to 25 mm height). All redrawn from Van Dover and Kirby-Smith (1979). 



and can be encrusting or erect with 

 finger-like projections (Figure 11C). 

 Next in intensity of color is the bright 

 orange, massively encrusting Xestospongia 

 hal i chondrioides . Other sponges are 

 rather drab. Mycale cecila is thinly 

 encrusting, slimy, and a pale yellowish 

 green or yellowish tan. Hal ichondria 

 bowerbanki assumes a variety of shapes, 

 starting as low encrustations, but often 

 developing a mass of ridges or branches 

 (Figure 11B). It is straw yellow, beige, 

 or pale orange in color. A number of 

 species of Hal iclona (Figure 11A) may be 

 found which are difficult to tell apart 

 without reference to spicules. They are 

 generally encrusting, softly spongy, and 

 gray, tan, or pinkish brown in color. 

 Finally, Lissodendoryx isodictval is is a 

 thickly encrusting sponge with a crisp 



consistency and is blue-green or yellow- 

 green in color. When broken open it is 

 said to smell of garlic. Because of the 

 variation in color and shape, spicules 

 should be examined for positive 

 identification (Wells et al . I960). 



Tubularia crocea is one of the most 

 conspicuous hydroids, forming large tufts 

 of long, unbranched stalks topped with 

 pink zooids (Figure 12B). Other common 

 hydroids are the white, delicate Obel ia 

 di chotoma , Eudendrium carneum with its 

 intensely orange colonies, and Halocordyle 

 disticha (= Pennaria tiarella ) , which has a 

 long black central stalk with two pinnate 

 rows of side branches bearing polyps 

 (Figure 12A). In protected waters 



Hydractinia echinata forms a white, fuzzy 

 encrustation over the substrate. Other 



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