Body with an anterior region of fifteen setigerous somites separated from a larger posterior region by a specialized somite, the sixteenth. Prostomium with a lateral process or horn on each side in front, notched in front at middle. Eyes none in genotype. Dorsal cirri present in addition to branchiæ on the first four setigerous somites. Notopodia with simple capillary setæ throughout. Anterior neuropodia with capillary setæ, but others also with crochets. Anal. cirri two.
Genotype—M. duplex sp. nov.
Morants duplex sp. nov.
Palpal processes lost from type. Proboscis as protruded short, distally expanded over proximal region. Parapodia dorsolateral in position, the anterior ones very thick. Principal postsetal lobe rising above into a branchial process which is short anteriorly but in posterior region is much longer, slender and subulate. Mesad of the branchial process of each parapodium of the first four pairs is a cirrus or cirriform process. The inferior setæ of the most anterior parapodia' much shorter than the dorsals, strongly curved. In the first notopodial fascia a much stouter, aciculiform, setæ which is uncate. Crochets with strongly narrowed neck; with two curved teeth at distal end above the beak which is decurved; in posterior region few in number, commonly four in a series. Anal cirri slender, filiform, much longer than the preceding branchiæ; one in the type has a short spur near its base. Total number of segments about one hundred and sixteen.
Length, 21.5 mm.
Type—M. C. Z. 2, 165.
Balboa.
The tubes adhere closely to the body. Their walls of fine sand.
AMPHARETIDÆ
Schistocomus gen. nov.