samples, P. deichmannae occurred between 7 and 37 m 

 with the highest densities (50-80/m'') occurring in <30 m 

 (Table 31). Eight of the nine stations >30 m occurred in 

 the Chesapeake Bight, suggesting that this species oc- 

 curs at slightly greater depths in the warmer southern 

 waters. 



Table 31. — Bathymetric distribution of Protohauti- 

 toriug deichmannae in samples from Middle Atlan - 

 tic Bight. 



Sediment Relationship. This species has been found 

 on fine sand or silty-sand (Bousfield 1973). We collected 

 P. deichmannae on sand (26/34), shelly sand (6/34), 

 shell (1/34), and silty sand (1/34). 



Protohaustorius wigleyi Bousfield 1965 



sand (9/88), 

 (Table 33). 



shell (1/88), and sand (77/88) bottoms 



Table Xl. — Sediment associations of ProtohauHtorius 

 wigleyi in samples from Middle Atlantic Bight. 



P8eudohau8toriu8 borealia Bousfield 1965 



Geographic Distribution. This species has been col- 

 lected between Georges Bank and Virginia (Bousfield 

 1973). In our collections, P. borealis occurred in 27 sam- 

 ples at 24 stations between Cape Cod and Virginia (Fig. 

 17). This species was moderately abundant where it oc- 

 curred, with a mean density of 50/m^ ranging between 

 2/m- and 600/m-. 



Geographic Distribution. This species has been 

 reported to occur from Maine to North Carolina along 

 the American Atlantic coast (Bousfield 1965). We col- 

 lected P. wigleyi in 88 samples from 80 stations between 

 Cape Cod and Cape Hatteras (Fig. 17). The mean den- 

 sity of this species was 40/m^ ranging between 2/m^ and 

 270/m^. Protohaustorius wigleyi showed no consistent 

 change in density with latitude, but it did occur more 

 frequently in the southern portion of our study area. 



Bathymetric Distribution. Bousfield (1973) found P. 

 wigleyi from shoreline to 150 m. In our collections, this 

 species occurred between 12 and 91 m. The mean den- 

 sities showed no clear trends with depth, but the bulk of 

 the samples were found between 20 and 49 m (Table 32). 

 Protohaustorius wigleyi showed no evidence of chang- 

 ing its depth distribution with latitude. 



Table .■i2. — Bathymetric distribution of Protohaus- 

 torius wigleyi in samples from Middle Atlantic 

 Bight. 



Bathymetric Distribution and Sediment Relation- 

 ship. Bousfield (1973) found this species on medium to 

 coarse sands between 10 and 60 m. In our samples, P. 

 borealis occurred between 22 and 62 m, but the majority 

 of the collections (19/27) and the highest densities (50- 

 70/m2) came from between 20 and 39 m (Table 34). All 

 24 stations were located on sand bottoms. 



Table :!J. — Bathymetric distribution of Pseudohaus- 

 torius borealis in samples from Middle Atlantic 

 Bight. 



Sediment Relationship. This species is usually as- 

 sociated with sandy sediments (Bousfield 1973). In our 

 collections, it was found on gravelly sand (1/88), shelly 



Family ISCHYROCERIDAE 



Cerapus tubularis Say 1818 



This species occurs from Cape Cod to eastern Florida 

 on muddy sand to depths of 30 m (Bousfield 1973). We 

 collected C. tubularis at two stations in Delawtire Bay at 

 shallow depths (4-9 m) on silty sand sediments (Fig. 18). 

 The scarcity of C. tubularis in our collections is most 

 likely due to its preference for depths shallower than 10 

 m where we took few samples. 



Ericthoniua braailiensis (Dana) 1853 



This tube-dwelling species has been reported from 

 Cape Cod to the West Indies in bays and estuaries 



31 



