POLYCHAETE WORMS — PETTIBONE 571 



sandy mud, mud with rock, rubble; 10 specimens. Stations 20, 47, 

 48, 52, 69. 



Distribution: Widely distributed in the Arctic. Also Iceland, 

 Faroes to Great Britain; Labrador to Long Island Sound; Bering Sea 

 to western Mexico; north Japan Sea. In low water to 190 fathoms. 



Family Ampharetidae 



Key to the genera of Ampharetidae from Labrador 



1. With a pair of large, recurved, dorsal hooked setae behind the branchiae. 



Branchiae 8. Without paleae. Thoracic setigers 16 (first 2 may be small). 



Melinna 

 Without pair of dorsal hooked setae posterior to branchiae 2 



2. With well developed bundles of golden setae (paleae) on each side, anterior to 



branchiae. Branchiae 8. Thoracic setigers 14. Uncinigerous pinnules 



begin on setiger 3 Ampharete 



Without paleae or paleae poorly developed (smaller and more delicate than 

 notosetae, easily overlooked) 3 



3. Uncinigerous pinnules begin on setiger 3. Branchiae 8. Thoracic setigers 13. 



Paleae very reduced or absent Sabellides 



Uncinigerous pinnules begin on setiger 4 4 



4. Branchiae 8. Without paleae or paleae very small and delicate. Thoracic 



setigers 16 (first small, easily overlooked) Lysippe 



Branchiae 6. Without paleae. Thoracic setigers 17 (first very small, easily 

 overlooked) Samytha 



Genus Melinna Malmgren, 1865 



Melinna cristata (Sars, 1851) 



Sabellides cristata Sars, 1851, p. 205. 



Melinna cristata Malmgren, 1865, p. 371, pi. 20, fig. 50.— Verrill, 1881, pp. 298, 

 302, 305, 309, 312.— Webster and Benedict, 1884, p. 732; 1887, p. 748.— 

 Moore, 1908, p. 349.— Fauvel, 1927, p. 237, fig. 83,i-n; 1933, p. 63.— Annen- 

 kova, 1937, p. 186; 1938, p. 199.— Zatsepin, 1948, p. 149, pi. 37, fig. 6.— 

 Hartman and Reish, 1950, p. 42. — Wesenberg-Lund, 1950a, p. 49; 1950b, 

 p. 114; 1951, p. 105; 1953, p. 93.— Berkeley and Berkeley, 1952, p. 70, figs. 

 143-145. 



Melinna cristata heterodonta Moore, 1923, p. 212, pi. 17, fig. 25. 



Description: Branchiae 8, united by a palmar membrane of 

 variable height. Anterior few segments coalesced, forming a col- 

 larette ventrally, with sides elevated in a lateral crest, and with a 

 transverse dorsal fimbriated thoracic membrane (10-20 teeth). 

 Abdominal region long, tapered posteriorly, about 50 segments. 

 Pygidium without cirri. Tube of mud with few small pebbles. 



New records: Labrador: Hamilton Inlet, 5-6 fms., sand, mud, 

 rock, much detritus; 1 specimen, Station 23. East Coast North 

 America: Off Nova Scotia, Maine, Massachusetts, 6-374 fms., 

 U. S. Fish Commission (identified by Verrill). 



