1428 



Owen, G., E. R. Trueman, and C. M. Yonge. 19 53. 



The ligament in the Lamellibranchia. Nature 171(4341): 73-75. 



This is a general discussion of the origin and structure of the ligament. 

 Few species are mentioned, and Mereenaria (Venus) mereenaria is not included. 

 In each group of Lamellibranchia the ligament has a characteristic formation, 

 "internal" or "external", elongated or condensed, with primary and secondary 

 constituents variously developed. No general description will cover all 

 cases. The ligament primarily consists of a superficial periostracum and an 

 "outer" and an inner, layer, corresponding to the three layers of the shell. 

 The 3 layers have different origins. Periostracum is secreted by a groove 

 between outer and middle lobes of mantle edge. Mantle edge secretes largely 

 uncalcified organic matter to produce the "outer layer", and the bulky inner 

 layer of the ligament is secreted by epithelium of the isthmus, the connecting 

 neck of tissue between the 2 lobes of the mantle, which has been called 

 erroneously pallial suture. - J.L.M. 



1429 



Palincsar, Joan Shriner. 1959. 



Periodisms in amount of spontaneous activity in the quahog, Venus mereenaria. 

 Ph.D. dissertation, Northwestern Univ. (1958). Dissert. Abstr. 19(3): 2640. 



Activity of V. mereenaria was recorded continuously for ten 29-day periods 

 during four years from 1954-1957. Single-day cycles showed some characteristics 

 of overt activity cycles with major maximum usually in daylight, but highly 

 variable. Diurnal cycles of 29 days were quite similar, usually unimodal, and 

 the major maximum of the day tended to shift from morning to afternoon in 

 alternate yrs. Average range was about 45%. Calculated 29-day lunar-day 

 cycles had a range of only about 20%, and points on the same curve of 

 individual cycles were not significantly different. A mean cycle for the 4 yrs, 

 however, showed a significant maximum 3 to 6 hrs after lunar zenith and a 

 minimum about lunar nadir. An hypothesis was suggested which combines 

 endogenous and exogenous rhythmic control mechanisms. (Abstracter's note: 

 the abstract was not very carefully written, and the meaning was not always 

 entirely clear. The hypothesis mentioned was not further explained. The 

 original thesis was not examined,) - J.L.M. 



1430 



Palmer, Katherine van Winkle. 1927. 



The Veneridae of eastern America, Cenozoic and Recent. Paleont. Amer. 1(5): 

 209-522, pis. 32-76. 



Genus VENUS (Linnaeus) Lamarck 



Venus Linnaeus, 1758, Systema Naturae, ed. X, p. 684; Linnaeus, 1767, ed. XII, 

 p. 1128; Gmelin, 1792, Systema Naturae, Tome VI, p. 3266; Lamarck, 1799, 

 Prodome, p. 84. 



Mereenaria Schumacher, 1817, Essai d'une Meth., p. 135; Gray, 1847, Proc. Zool. 

 Soc. Lond., p. 183; Deshayes, 1853, Cat. Conch. Biv. Sh. Brit. Mus., pt. I, p. 

 113; H. and A. Adams, 1857, Gen. Rec. Moll., vol. II, p. 418; Stoliczka, 1871, 

 Pal. Indica, vol. Ill, p. 153; Tryon, 1884, Struct, and Syst. Conch., vol. Ill, 

 p. 176 not Cossmann, 1887, Cat. Illus. 



Venus Fischer, 1887, Man. de Conch., p. 1083 not Venus H. and A. Adams, 1857. 

 Crassivenus Perkins, 1869, Proc. Bost. Soc. Nat. Hist., vol. XIII, p. 147. 

 Venus Dall, 1902, Proc. U.S. Nat. Mus., vol. 26, No. 1312, p. 360; Dall, 1903, 

 Trans. Wag. Inst. Sci., vol. Ill, pt. 6, p. 1307; Cossmann and Peyrot, 1911, 

 Actes Soc. Linn. Bordeaux, Tome LXIV, p. 322; Jukes-Browne, 1914, Proc. Mai. 

 Soc. Lond., vol. 11,. p. 79. 



400 



