_Scoloplos armiger_ Müll. is extremely common on our coast. It is about an inch long, yellowish, with red gills, commencing about the twelfth segment. Each of the lobes of the parapodium possesses an aciculum, and the chaetae are bent in a peculiar way. The everted buccal region has the form of a six- or eight-rayed star. The spawn of this species may be found on the shore in spring as brown, pear-shaped, jelly-like masses, each with a long stalk, by which the mass is fixed to the sand. In the jelly are the eggs, which may be watched passing through the earlier stages of development. Atlantic on both shores, even off Spitzbergen, and Nova Zembla. Another representative is _Theodisca mamillata_ Clap., which occurs amongst the roots of _Laminaria_. FAM. 13. _Typhloscolecidae._[382]—Pelagic, greatly modified forms, apparently related to the Phyllodocidae, but with very uncertain affinities. The prostomium is pointed and carries a pair of foliaceous tentacles; each of the first two segments bears a pair of foliaceous cirri; the remaining segments possess a dorsal and a ventral pair of foliaceous cirri, with a small bunch of chaetae and a single aciculum. All the cirri have peculiar rod-cells. _Typhloscolex_ Busch, _Sagitella_ Wagner, and _Travisiopsis_ Uljanin: all small worms. North Sea Atlantic. SUB-ORDER 2. SPIONIFORMIA. FAM. 1. _Spionidae._—Mostly small worms, with small ridge-like prostomium carrying a pair of eyes, but no tentacles or palps. The peristomium, which extends forwards on each side {322}of the prostomium, bears a pair of very long cirri (usually termed "tentacles") normally directed backwards, very mobile, and more or less coiled. They are readily thrown off by the animal. The notopodial cirri are long, finger-shaped, and curved over the back; they are vascular and ciliated, and function as "gills." The neuropodia project laterally. Both are usually provided with a "podal membrane" along their outer margin. There are no ventral cirri; the dorsal chaetae are fringed capillaries; the ventral are "crotchets." The buccal region is eversible. The worms burrow in mud and sand. _Spio seticornis_ Fabr. is a small worm less than an inch in length, colourless except for the red blood in its vessels. It builds long and flexible tubes of sand in the clefts of rocks and under stones in the upper part of the littoral zone. The prostomium is notched at the anterior margin. The gills commence on the twelfth segment, and do not extend to the end of the body. A membrane-like cirrus exists also on the second chaetigerous segment. The podal membrane is adnate to the gill throughout its extent. Four short anal cirri occur. Greenland and Scandinavia. [Illustration: FIG. 172.—_Nerine vulgaris_ Jnstn., enlarged. (From Cunningham.) _a_, Prostomium; _c^1_, cirrus of peristomium; _c^2_, "gill"; _l_, lobes; _m_, podal membrane; I, peristomium; II, III, IV, following segments.]