832 NATURAL HISTORY OF AQUATIC ANIMALS. 



anteriorly, but farther back often become bright red owing to the numerous blood-vessels that 

 they contain. It is a very active and voracious Worm, and has a large, retractile proboscis, armed 

 with two strong, black, hook-like jaws at the end, and many smaller teeth on the sides. It feeds 

 on other Worms and various kinds of marine animals. . It captures its prey by suddenly thrusting 

 out its proboscis and seizing hold with the two terminal jaws ; then withdrawing the proboscis, 

 the food is torn and masticated at leisure, the proboscis, when withdrawn, acting somewhat like a 

 gizzard. These large Worms are dug out of their burrows and devoured eagerly by the tautog, 

 scup, and other fishes. But at certain times, especially at night, they leave their own burrows, 

 and, coming to the surface, swiin about like eels or snakes, in vast numbers, and at such times fall 

 an easy prey to many kinds of fishes. This habit appears to be connected with the season of 

 reproduction. They were observed thus swimming at the surface in the daytime, near Newport, 

 in April, 1872, by Messrs. T. M. Prudden and T. H. Russell, and I have often observed them 

 in the evening later in the season. At Watch Hill, Rhode Island, April 12, I found great 

 numbers of the males swimming in the pools among the rocks at low water, and discharging their 

 milt. This Worm also occurs in many other situations, and is abundant in most places along 

 sandy and muddy shores, both of the sounds and estuaries, burrowing near low-water mark. 

 It occurs all along the coast from New Tork to the Arctic Ocean, and is also common on the 

 northern coasts of Europe. 



" With the last, in this region and southward, another similar species, but of smaller size, is 

 usually met with in large numbers. This is the Nereis limbata. It grows to the length of five or 

 six inches, and can easily be distinguished by its slender, sharp, light amber-colored jaws, and by 

 the lateral lamellae, which are small anteriorly and narrow or ligulate posteriorly. Its color, when 

 full grown, is usually dull brown, or smoky brown or bronze-color anteriorly, with oblique light 

 lines on the sides, and often with a whitish border to each of the rings, which form n?*rrow, pale 

 bands at the articulations ; posteriorly the body and lateral appendages are pale red, and the 

 longitudinal dorsal bloodvessel is conspicuous. 



" Annelids are quite numerous on the sandy shores where the conditions are favorable. It 

 is evident that these soft-bodied creatures would be quickly destroyed by the force of the waves 

 and the agitation of the sand were they not provided with suitable means for protecting them- 

 selves. This is effected mainly in two ways : the sand-dwelling species either have the power of 

 burrowing deeply into the sand with great rapidity, or else they construct long, durable tubes, 

 which descend deeply into the sand and afford a safe retreat. Many of the active burrowing 

 species also construct tubes, but they usually have but little coherence and are not very perma- 

 nent, nor do they appear to be much relied on by the owners. There is, however, great diversity 

 both in the structure and composition of the tubes of different species, and in the modes by which 

 the rapid burrowing is effected. 



" The large green Nereis (N. virena) is found on the sandy shores in places that are somewhat 

 sheltered, especially if there be an admixture of mud or gravel with the sand to give it firmness 

 and solidity. This species burrows deeply beneath the surface and lines the interior of its large 

 irregular burrows with an abundant mucus-like secretion, which gives smoothness and some 

 coherency to the walls, but does not form a solid tube. With this, and in greater numbers, the 

 smaller species, Nereis limbata, is also found, and its habits appear to be essentially the same. 

 Both this and the preceding can burrow rapidly, but much less so than some other worms, and 

 consequently they are not well adapted to live on exposed beaches of moving sands, but prefer 

 coves and harbors. The two large species of EJiyncliololvs are much better adapted for rapid 

 burrowing. Their heads are very small and acute, and destitute of all appendages, except four 



