{397] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 103 
Lepidonotus squamatus, (p. 320, Plate X, figs. 40, 41;) LD. sublevis V., 
(p. 320, Plate X, fig. 42;) and Harmothoé imbricata, all of which 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 ascidians, 
barnacles, roots of alge, or in the cavities of sponges, &c. Several 
long, slender, and active species, belonging to the genera Phyllodoce, Hu- 
lulia, Humidia, and Hteone, are of frequent occurrence; most of them are 
bright green or yellowish green in color, and all have small, leaf-like 
branchiz 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, Amaracium 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 Lumbriconereis 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 Dane, 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, 88a;) Nicolea simplex, 
(p. 321;) Scionopsis palmata, (p. 321;) Potamilla oculifera, (p. 322,) Plate 
XVIL, fig. 86 ;) Sabella microphthalma, (p. 323 ;) Serpuladianthus, (p 322 5) 
and Fabricia Leidyi, (p. 323,) all occur in tubes attached to the rocks 
and stones. 
A species of Spirerbis, which forms a small, white, calcareous shell, 
coiled up in an open spiral, is commonly attached to the alg and hydroids. 
The Avutolytus cornutus (Plate XITI, figs. 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- 
