portion of the disk shows fine and even radial lines between the concentric 

 ones. Venus mercenaria alba Dall lacks purple coloration and has no brown 

 markings. Venus campeahiensis Gnielin: larger, rounder, much thicker shell 

 than V. mercenaria, usually white inside and out; lower posterior angle of 

 pallial line more acute, scalloping of inner margin finer, arrangement of 

 cardinal teeth less fanlike; length 4 inches. Juvenile shell less convex 

 than in other species, lunule and escutcheon brown with fine pale zigzag 

 lines. Occasionally in the umbones cavity a pale purple tinge, which is 

 lacking in V. mercenaria. Mutations are similar to those of V. mercenaria 

 except that the center of the disk is never entirely smooth. Sometimes a 

 trace of purple at margin. This is the persistent type beyond the Mississippi 

 delta, especially in Texas. Abundant in Yucatan. Chesapeake Bay to Cuba. 

 V. campeahiensis alboradiata Sowerby has brown rays on a pale ground; Gulf of 

 Mexico. V. campeahiensis quadrata Dall has a thin shell, small, subquadrate, 

 and uncolored. Venus campeahiensis texana Dall has the concentric lines 

 toward center of disk coalescent, ribs flat- topped with polished tops, valves 

 usually extremely convex; Texas. - J.L.M. 



1699 



Smith, Osgood R. 1952. 



Small clams move into a flat, see the sights, and move on. Maine Coast 

 Fisherman 7(3): 20. 



The species is not identified, but it is probably My a arenaria rather than 

 Mercenaria (Venus) mercenaria. The conclusions might apply to either species, 

 however. The gist of the article is that abundance and distribution of newly 

 metamorphosed clams do not necessarily provide a forecast of future 

 abundance or distribution. During the stage in which they are attaching and 

 reattaching by a byssus thread clams may move considerable distances and be 

 resorted by attaching to loose marsh grass and other drifting debris. Many 

 questions about distribution, abundance, and survival remain to be answered. 

 - J.L.M. 



1700 



Smith, Osgood R. 1954. 



The wanderings of small clams. Ann. Meeting Natl. Shellf. Assn., 12-14 Aug. 

 1952: 105-107 (date of publication estimated). 



Large scale movements of recently set or juvenile My a arenaria take place by 

 rafting of newly set clams attached to algae or debris. Older juveniles are 

 active and move laterally for considerable distances. Mercenaria (Venus) 

 mercenaria is not mentioned. - J.L.M. 



1701 



Smith, Rebecca Joyce. 1958. 



Filtering efficiency of hard clams in mixed suspensions of radioactive 

 phytoplankton. Proc. Natl. Shellf. Assn. 48: 115-124. 



Removal of phytoplankton from suspension by Mercenaria was measured by 

 labeling a species of Carteria with Ca45 and other types of phytoplankton 

 with P 3 2. clams varied from 80 to 88 mm long. Algal cells 2-3 microns in 

 diameter are not removed as efficiently as larger cells in the same 

 suspension. Algal cells 4 microns and larger are retained by the clam 

 with the same efficiency. Gymnodinium sp. caused most clams to close soon 

 after filtering began. Density of algal cells in suspension did not affect 

 filtering efficiency of clams. - D.L. 



1702 



Smith, Sanderson. 1862. 



On the Mollusca of Peconic and Gardiner's Bays, Long Island, New York. Ann. 

 Lye. Nat. Hist. N.Y. 7(20): 147-168. 



Ninety-six molluscan species are reported from these two bays at the eastern 

 end of Long Island. Venus mercenaria was moderately abundant, Venus (Gemma) 

 gemma very abundant. - J.L.M. 



471 



