pies from Horseshoe Cove as late as 5 November, 

 but only until 1 October and 21 August at Ward 

 Point and New Dorp Beach, respectively. Par- 

 tially spent clams were collected from Horseshoe 

 Cove and New Dorp Beach as late as 13 January 

 1975, but only until 5 November 1974 at Ward 

 Point. The spent and early gametogenic stages 

 identified in clams from all sites by 6 February 

 1975 indicated that the 1974 reproductive cycle 

 had been completed by all clams and that a new 

 cycle had begun for some. These observations sug- 

 gest that the spawning period was shortest at 

 Ward Point (5 months) and longest at New Dorp 

 Beach (7 months), with Horseshoe Cove interme- 

 diate (6 months). 



At all three sites, gametogenesis progressed 

 through morphologically normal stages resulting 

 in the complete spawning of most ripe gametes. 

 Cytolysis of unspent cells was not observed. No 

 hermaphrodites were seen in any of the samples. 



The sex ratios of hard clams in the samples 

 were as follows: at Ward Point, 59 males and 60 

 females; at New Dorp Beach, 56 males and 64 

 females; and at Horseshoe Cove, 74 males and 45 

 females. The hypothesis of 1:1 sex ratio was 

 tested by chi-square for all three populations; re- 

 sults indicated a significant (P < 0.01) deviation 

 for Horseshoe Cove. 



Histochemical Tests for Metals 



Histochemical tests were performed on four 

 male and six female hard clams and one male and 

 one female oysters collected at Ward Point; and 

 three male and seven female hard clams collected 

 at New Dorp Beach. The expected histochemical 

 reactions for metals in clam tissues were not ob- 

 served, i.e., deep Prussian blue for inorganic iron, 

 green granular precipitate for arsenites and arse- 

 nates, yellow opaque crystals or scarlet red pre- 

 cipitate by the chromate or rhodizonate methods, 

 respectively for lead, and deep greenish-black 

 precipitate for copper. Thus, the tests for metals 

 in hard clam tissues proved to be negative. Fe- 

 male gonadal tissues tested for arsenites and ar- 

 senates from both collecting sites had 1-2 \xm di- 

 ameter granules in the oocyte cytoplasm but the 

 color could not be determined. No similar gran- 

 ules were seen in male tissues. For the two oys- 

 ters from Ward Point, the deep greenish-black 

 precipitate for copper was evident in connective 

 tissue cells beneath the body wall and palps (a 

 similar reaction was also seen in the epidermal 

 cells of the palps), around the digestive divertic- 



ula (Fig. 3), and near the base of cells lining the 

 gills and gut. The connective tissue cells sur- 

 rounding the male oyster gonadal tubules also 

 tested positive. No similar reaction was seen in 

 the connective tissue cells surrounding the fe- 

 male oyster gonadal tubules, which contained 

 large and apparently normal oocytes. Although 

 not seen in New Dorp Beach hard clam tissues, 

 some gill tissues of hard clams from Ward Point 

 tested for copper showed a slight darkening, but a 

 precipitate was not clearly evident, such as was 

 seen in oysters. The darkening was also absent in 

 underlying connective tissue cells and other tis- 

 sues. Modification of the technique to intensify 

 the copper reaction was negative for all hard clam 

 and oyster tissues from the two collection sites. 



Discussion 



Shell dimensions and shell and body weights 

 clearly indicated a smaller size for hard clams at 

 Ward Point than at New Dorp Beach and Horse- 

 shoe Cove, which was reflected in the age esti- 

 mates. Clams at Ward Point were younger (none 

 >14 years) and smaller {X = 77 mm; none >97 

 mm) than clams at New Dorp Beach (none >20 

 years; X = 88 mm; none >113 mm). These are 

 values much lower than the 111 mm mean and 

 maximum length of 144 mm reported for Nan- 

 tucket Sound hard clams by Ropes and Martin 

 (1960) and recent, almost 60-yr longevity esti- 

 mate for the species (Ropes pers. obs.). 



Determination of the percentage solids for the 

 meats of bivalves is a measure of condition (Engle 

 and Chapman 1953). The following mean values 

 have been reported: 18.4% for soft-shell clams, 

 Mya arenaria (Harriman 1954), 17.09^ for oysters, 

 C. virginica (Engle 1958), 21.4% for surf clams, 

 Spisula solidissima (Barker and Merrill 1967), 

 and 18.5% for ocean quahogs, Arctica islandica, 

 (Ropes 1971a). These compare favorably with 

 16.5% and 15.8% for Horseshoe Cove and New 

 Dorp Beach hard clams, respectively (Table 1). 

 The low value of 14.3% for Ward Point hard clams 

 is an indication of poor condition. 



Reported age and growth determinations for 

 hard clams suggest that the Ward Point portion of 

 the Raritan Bay population was being adversely 

 affected. Ansell (1968) has extensively reviewed 

 the literature on annual and seasonal growth of 

 hard clams from various investigations in 

 Canada, the United States, and Europe. Length- 

 on-age observations of the growth of hard clams 

 at sites in Florida, North Carolina, New Jersey, 



658 



