24 B Canadian Arctic Expedition, 1913-18 



One specimen of typical structure. Scars show the normal three pairs of 

 branchiae to have been present in two separated groups; but only one branchia 

 remains in place on the specimen at present. 



This is a primarily Arctic species of probably circumpolar distribution. 

 It was previously known from the waters of Sweden, Spitzbergen, Greenland, 

 Davis strait, Labrador, and New England. 



Ampharete johanseni, n. sp. 



Type specimen. Cat. No. 39, Victoria Memorial Museum, Ottawa. 

 Paratype, Mus. Comp. Zool., No. 2193. Two specimens. 



This species seems generally to be readily recognizable from the character- 

 istics of the branchiae. The branchiae of the two groups are only very narrowly 

 separated at the middle line and the two mesal ones are connected at base by 

 a rather high membrane. The first, second, and fourth branchiae on each side 

 counting from the most ectal, are in a transverse line and are of the same general 

 size; but the third is crowded often a little caudad of the others and is charac- 

 teristically much smaller in size, though varying considerably in the amount 

 of its reduction. 



The palese number typically from nine to twelve on each side. Slenderly 

 attenuated to a fine tip, but the latter not at all abruptly set off. (See PL V, fig. 1.) 



There are thirteen setigerous thoracic somites. The setae narrowly limbate 

 and finely tipped as usual. The uncini have only four teeth in each series, the 

 plate as a whole subquadrate, with the abdental edge evenly curved, not shoul- 

 dered or angulate. (See pi. V, fig. 2.) 



First abdominal uncinigerous tori large, with edges rounded, the others 

 progressively reduced in going caudad. No cirri were detected on any of them. 



The type is 16 mm. long. A second specimen, which is incomplete caudally, 

 is considerably broader. 



LOCALITY. Alaska: off Collinson point. Station 27s. October 3, 1913. 

 Depth, 3 fathoms. Bottom, mud and gravel, with algae. 



The tubes are composed of grains of sand adhering to a tough lining mem- 

 brane. 



Ampharete reducta, n. sp. 



Type specimen. Cat. No. 40, Victoria Memorial Museum, Ottawa. 

 Paratype, Muis. Comp. Zool., No. 2192. Two specimens. 



A species somewhat suggesting A . arctica in the form of the paleae ; but 

 the tips are much more elongate and less abruptly set off, not shortly mucronate. 

 (See PL V, fig. 3.) Also the paleae are only half or less as numerous as in arctica, 

 the number in each ^roup being five or six. The paleae are obviously coarser 

 than in johanseni. 



The branchiae have the ordinary general arrangement, but with the ectal 

 one of each group caudad of the general line, in the type being almost caudad 

 of the adjacent one. 



The usual fourteen pairs of fascaiae of capillary thoracic setae. These setae 

 limbate and finely tipped, as shown in PL V, fig. 5. 



The uncini are of the same general type as in johanseni; but they are 

 smaller and there are five teeth in each series in place of four and the end away 

 from which the teeth are directed is less rounded, being slightly indented as in 

 arctica but without so distinct an angle or shoulder as in the latter. (See pi. V, 

 fig. 4.) 



Length, 20 mm. 



LOCALITY. Alaska: off Collinson point. Station 27s. October 3, 1913. 

 Depth, 3 fathoms. Bottom, mud and gravel with algae. 



Found with specimens of johanseni. The tubes of the two species are alike 

 in structure and appearance. 



