[397] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 103 



sqiiamatus, (p. 320, Plate X, figs. 40, 41;) L. mblevisV., 

 (p. 320, Plate X, fig. 42?) and Harmothoe imbricata, all of whidi cling 

 close to the rough surfaces of the stones, or hide away in the cracks and 

 crevices, or conceal themselves in the interstices between the aseidians, 

 barnacles, roots of algas, or in the cavities of sponges, &c. Several 

 long, slender, and active species, belonging to the genera Phyllodoce, Eu- 

 hilia, En mid ia, and Eteone, are of frequent occurrence ; most of them are 

 bright green or yellowish green in color, and all have small, leaf-like 

 brand) i;e along the sides. 



The Nereis pelagica (p. 319, Plate XI, figs. 52-55) is very common, 

 living beneath the stones, and especially in the interstices between the 

 lobes of a large, sand-covered, compound ascidian, Amarcecium pelluci- 

 dum, in company with the species of Phyllodoce, &c., just named. This 

 species of Nereis is remarkable for its brilliant iridescence. It is a 

 northern species, extending to the Arctic Ocean and northern coast of- 

 Europe. It is very abundant on the coast of Maine, under stones 

 at low-water mark. 



Associated with the preceding species among the sandy compound 

 ascidians, occurring both on rocky and gravelly bottoms, were large 

 numbers of the Liimbriconereis opalina, (p. 320, Plate XIII, figs. 69, 

 70,) conspicuous on account of the brilliant iridescent colors. Several 

 other Annelids also occurred among these ascidians. The Cirrinereis 

 fragilis, which is a small and delicate species, furnished with con- 

 spicuous eyes, and related to the large Cirratulus, occurs beneath the 

 stones. The singular Naraganseta coralii occurs burrowing in the coral, 

 Astrangia Dance, and in this respect is similar in its habits to the allied 

 genus Dodecacerea, which excavates its galleries in the solid shells of 

 Cyprina Islandica, Pecten tenuicostatus, &c., in the Bay of Fundy. The 

 Sabellaria vulgaris, (p. 321, Plate XVII, figs. 88, 8Sa ;) Nicolea simplex, 

 (p. 321 ;) Sdonopsis palmata, (p. 321;) Potamilla oculifera, (p. 322,) Plate 

 XVII, fig. 86 ;) Sabella microphthalma, (p. 323 ;) Serpula diantlms, (p 322 ;) 

 and Fabricia Leidyi, (p. 323,) all occur in tubes attached to the rocks 

 and stones. 



A species of Spirorbis, which forms a small, white, calcareous shell, 

 coiled up in an open spiral, is commonly attached to the algae and hydroids. 

 The Autolytus cornutus (Plate XIII, tigs. 65, 66) constructs cylindrical 

 tubes, which are attached to sea- weeds and the branches of hydroids. 

 This is a small flesh-colored species, with conspicuous brown eyes ; the 

 ends of the body are often tinged with green, and the dark, greenish 

 intestine shows through as a median line. The males and females 

 are widely different in appearance and structure, and there are also 

 asexual individuals (fig. 65) very different from both. The asexual ones 

 construct the tubes referred to, but do not remain in them constantly, 

 for they are also often taken swimming at the surface. The males and 

 females are also taken at the surface, especially in the evening, but they 

 also occur creeping over and among the hydroids. This worm is partic- 



