Sand and silty sand substrates contained the largest 

 amounts of both samples. 24 and 29% respectively, and speci- 

 mens, 44 and 36% respectively. Other sediment types con- 

 tained significantly smaller quantities with the exception of 

 shell and sand-shell sediments from which they were absent 

 (Table 221). There are five samples containing eight speci- 

 mens which are unclassified with regard to sediment type. 



Macoma tenta (Say 1834). Tenta macoma. Figure 59. 



The tenta macoma is distributed throughout the northwest 

 Atlantic ranging from Newfoundland to Florida; it also occurs 

 at Bermuda, in the Gulf of Mexico, the West Indies, and 

 ranges south to Brazil (Johnson 1934; Morris 1951, 1973; La 

 Rocque 1953; Ockelmann 1958; Abbott 1968, 1974; Emerson 

 et al. 1976). 



Macoma tenta is a very common bivalve species of which 

 we have 708 specimens from 22 samples (Table 5). 



Our samples occur in the New England region. They are 

 located in the environs of Cape Cod, Mass., and the outer 

 islands, on the outer continental shelf of Georges Bank, and 

 the Gulf of Maine (Fig. 59; Theroux and Wigley footnote 4, 

 table 103). 



The main distribution of this species is Virginian, Carolin- 

 ian, and Caribbean in the Western Atlantic; the genus and 

 family are Celtic in Europe (Coomans 1962); Gosner (1971) 

 considered it to be Boreal and Virginian in distribution. 



The tenta macoma is essentially an inshore, shallow water 

 dweller with a depth preference ranging between 0.3 and 31m 

 (Abbott 1968, 1974; Porter 1974). 



Our samples range in depth between 1 and 73 m with a mean 

 of 24 m. The majority of samples and specimens are in the 

 shallowest, 0-24 m, depth range grouping which contains 68% 

 of the samples and 98% of the specimens; the 25-49 m group- 

 ing contains 14% of the samples and 0.6% of the specimens 

 while the 50-99 m grouping contains 18% of the samples and 

 2% of the specimens (Table 222). 



Abbott ( 1 968 , 1 974) , and Emerson et al . ( 1 976) reported that 

 this species is normally found in sand or muddy substrates. 



The majority of our samples (46%) occurred in sand; the 

 largest number of specimens (73%) occurred in clay. Sand- 

 gravel substrates contained 18% of the samples and 8% of the 

 specimens; sand contained 16% of the specimens; silty sand 

 substrates contained 9% of the samples and 3% of the speci- 

 mens, and clay contained 27% of the samples (Table 223). 

 There are 11 samples containing 671 specimens which are 

 unclassified with regard to sediment type. 



Macoma sp. Figure 60. 



There are 12 specimens from 10 samples in the NEFC 

 collection which bear the designation Macoma sp. (Table 5). 



Our samples containing members of this genus are from two 

 of the primary fishing banks in the area, Browns Bank and 

 Georges Bank, and also from coastal waters of Massachusetts 

 and off Long Island, N.Y. (Fig. 60; Theroux and Wigley 

 footnote 4, table 104). 



The NEFC samples are from water depths ranging from 1 to 

 103 m with a mean depth of 48 m. Thirty percent of the 

 samples are in the 0-24 m and the 25-49 m depth range group- 

 ings which contain 25 and 33% of the specimens, respectively; 

 20% of the samples occur in each of the 50-99 m and 100-199 m 

 groupings which contain 25 and 17% of the specimens, re- 

 spectively (Table 224). 



Fifty percent of the samples and specimens occurred in 

 sand substrates with 25% of the samples and 30% of the 

 specimens occurring in silt substrates; the coarse grained 

 fractions, gravel and sand-gravel, each contained 13% of the 

 samples and 10% of the specimens (Table 225). There are two 

 samples containing two specimens which are unclassified 

 with regard to sediment type. 



Genus Strigilla Turton 1822 

 Strigilla mirabilis (Philippi 1841). White strigilla. Figure 102. 



This southern species, which occurs in Bermuda, is also 

 found from Cape Hatteras, N.C., extending around the Flor- 

 ida Peninsula, into the Gulf of Mexico, where it extends from 

 Texas to the Yucatan in Mexico; it has also been reported 

 from Brazil (Johnson 1934; Boss 1969; Morris 1973; Abbott 

 1974; Emerson et al. 1976). 



The white strigilla is represented in the NEFC collection by 

 12 specimens from 9 samples (Table 5). 



The samples in the NEFC collection are from the continen- 

 tal shelf between Cape Fear, N.C., and Jacksonville, Fla. 

 (Fig. 102; Theroux and Wigley footnote 4, table 183). 



This species normally ranges in depth from just offshore at 

 + 1 to 57 m (Abbott 1968, 1974). 



Our samples range in depth from 6 to 30 m with a mean of 17 

 m. The 0-24 m depth range grouping contains 67% of the 

 samples and 75% of the specimens and the 25-49 grouping 

 contains 33% of the samples and 25% of the specimens (Table 

 226). 



Samples containing the white strigilla were obtained from 

 areas containing sand and sand-shell substrates. The former 

 contained 67% of the samples and 75% of the specimens, 

 while the latter contained 33% of the samples and 25% of the 

 specimens (Table 227). 



Genus Tellina Linne 1758 



Tellina aequistriata Say 1824. Striated tellin. Figure 103. 



The distribution of this species is from North Carolina to 

 Texas and Brazil; it also occurs in the West Indies (Johnson 

 1934; Boss 1966; Abbott 1968, 1974; Andrews 1971; Morris 

 1973). 



The NEFC collection contains one specimen from one 

 sample of this species (Table 5). 



Our sample comes from inshore waters south of Cape Fear, 

 N.C. (Fig. 103; Theroux and Wigley footnote 4, table 185). 



The depth range for the striated tellin is 2 to 64 m (Boss 

 1966; Abbott 1968). 



The NEFC sample is from a water depth of 20 m; this depth 

 places it in the 0-24 m depth range grouping. 



Both Boss (1966) and Andrews (1971) reported that this 

 species is normally found on sandy bottoms. Our sample was 

 also obtained from a sand substratum. 



7 



Tellina agilis Stimpson 1858. Northern dwarf tellin. Figure 103. 



This common bivalve occurs from the Gulf of St. Lawrence 

 to Georgia (Abbott 1968, 1974;Boss 1968;Morris 1973;Emer- 

 son et al. 1976). 



7 Abbott ( 1974) has "Stimpson. 1857" for this species, it should be Stimpson 

 1858. see under References. 



41 



