48. 



Both of the northern canyons have considerably more 

 diverse and abundant coral populations than are found in 

 Baltimore Canyon. Many of these corals are attached forms, 

 so this difference is a reflection of the greater amount of 

 hard substrate exposed in these canyons. This indicates that 

 the availability of suitable substrate plays a key role in 

 determining the distribution of many of these corals. 



Of the two northern canyons surveyed Lydonia Canyon has 

 a less abundant coral population than Oceanographer Canyon, 

 Three soft corals, one alcyonacean Eunephthya florida and the 

 two gorgonians Paramuriaea grandis and Acanthogorgia armata, 

 are the most common corals found in this canyon (Fig. 23) . 

 E, florida is found on the east wall along the axis, between 

 the depths of 500 to 700 meters, where it frequently occurs 

 in heavy concentrations. Several individuals of a closely 

 related species, E. glomerata observed on both the east and 

 west walls of the canyon. Paramuricea grandis and Aaanthogorgia 

 avmata are found in the axis and on the walls, with P. grandis 

 being more common in the deeper part of the axis (below 800 

 meters). Other soft corals, occurring along the axis of 

 Lydonia Canyon, that are restricted to hard substrates are 

 Paragorgia arboreaiFig, 25d) , Primnoa reseda^ Traohythela 

 Tudie, and Anthothela grandi flora. The solitary scleractinian 

 Desmophyllum aristagatli is also found on the outcrops in 

 the deeper part of the axis and in some areas on the west wall. 



