NO. 2 OLGA HARTMAN : SUBMARINE CANYONS 17 



fundibularis, in a thick mucus sheath ; Glycera capitata, in silt sur- 

 rounding the rock; Hypstco?nus calif ornicus, in cartilaginous tube 

 penetrating a rock; Laeospira sp., in sinistrally coiled tubes on rock 

 surface; Lepidonotus caelorus, in crevices in rock; Lu?nbriclymene sp., 

 abundant in drillings in rock; Peisidice aspera, abundant in rocky 

 crevices; Nicomache sp., nestling in arenaceous tubes in pits of rock; 

 Pherusa inflata, in U-shaped burrows in rock; Phyllochaetopterus 

 prolifica, in slender, irregular, opaque tubes ; Pista elongata, in long, 

 slender tube with reticulated top; Platynereis bicanaliculata, in mucoid 

 tube ; Polycirrus sp., nestling in crevices in rock ; polydorid, in U-shaped 

 drillings in rock ; Pseudopotatnilla sp., in cartilaginous tube penetrating 

 rock ; spirorbids, in transparent tube attached to rock surface ; Vermiliopsis 

 'iinfundtbulum, attached to rock ; Vermiliopsis Icornuta, attached to rock. 

 Echinoderms include Amphipholis pugetana; Amphipholis squa- 

 mata; Ophiacantha diplasia; Ophiopholis bakeri; Ophiura liitkeni; 

 Mediaster aequalis; Rathbunaster californicus; Sclerasterias hetero- 

 paes; Cucumaria crax; Psolus sp., holothurians, of several kinds. 



Mollusks include chitons, many small ; gastropods, numerous small, 

 of several kinds; Saxicavella pacifica; small white slug. 



These animals are members of a rock-bottom fauna, in shallow 

 to moderate depths. 



The shallowest quantitative sample from Dume canyon in 299 

 meters contained chiefly single individuals of deep water or shelf 

 species, some of which have their greater concentrations below or 

 above this level. Brissopsid urchins are prominent at 652 meters, and 

 tubicolous worms, especially Nothria pallida and Pista disjuncta, continue 

 prominent to 507 meters, after which they are replaced by Melinnexis 

 and Califia species. A ghost shrimp exists at 570 and 741 meters. A clam, 

 Compsomyax siibdiaphana, is present with many small individuals at 

 580 meters. 



SANTA MONICA CANYON 



This canyon (Fig. 5) was sampled in 80 to 873 meters. A sample 

 trawled at the head of the canyon, Nov. 30, 1958, by the Hyperion 

 Engineers, centered at 33° 56' 40", 118° 34' 00", along the 80 meter 

 contour, yielded rock specimens and many animals, some of which 

 are named : 



Polychaetes include Cirratulus cirratus; Eulalia sp., dorsum with 

 3 longitudinal rows of spots; Eunice multipectinata, in mucoid, parch- 



