CLASS I 



PELECYPODA 423 



elastic ligament, and closed by the contraction of muscles attached to the inner faces of 

 the valves ; feeding hj ciliary action and destitute of a radida or jaw ; breathing by 

 lateral gills ; imperfectly sensible to light and rarely provided with peripheral visual 

 organs ; possessing olfactory organs (osphradia), auditory and equilibrating organs 

 (otocysts), tactile papillae, and a nervous system composed of ganglia united by nerves, 

 but without a pedovisceral commissure; provided with an extensile, tactile or loco- 

 motor organ (foot) ; a circulatory system containing haemolympth, and operated by a 

 single or faired cardial ventricle and two auricles ; a more or less convoluted intestinal 

 canal, ivith its oral and anal extremities at opposite ends of the body ; a stomach ; 

 paired nephridia, connected with the pericardium, and discharging independently of 

 the rectum ; reproducing without copulation, by ova and spermatozoa ; monoecious or 

 dioecious ; development external to the ovary ; the post-larval stage protected by a 

 prodissoconch, and sometimes exhibiting specicd nepionic stages. 



External Characters. The Shell. — The embryonic Pelecypod is provided 



Palaeont. Soc, 1896-1905. — Ulrich, E. 0., Lower Silurian Lauiellibraiicliiata of Minnesota. Rept. 

 Geo!. Surv. Minn., 1897, vol. iii. 



B. On Mesozoic Forms : Benccke, E. W., Die Versteineruugen der Eisenerzformation von 

 Deutsch - Lotliringen unci Luxemburg. Abh. GeoL Spezialkarte Elsass - Lotliring., 1905, n.s., 

 vol. V. — Bittncr, A., Revision der Lamellibrancliiaten von St. Cassian. Abh. Geol. Reichsanst. 

 Wieu, 1895, vol. xviii. — Bulim, U., Die Bivalven der Stramberger Schichten. Palaont. Mittlieil. 

 Mus. Bayer. Staates, 1883, vol. u.—Borrissyak, A., Die Pelecypoden der Jura-Alilageruugen im 

 europaisclien Russland. Mem. du cours geol., nouv. ser., 1904-9. — Broili, F., Die Fauna der 

 Pacbycardientuffe der Seiser Alp. Palaeontogr., 1903-7, vols. 1., liv. — Coquand, W., Monographie 

 du genre Ostrea des terraips cretaces, 1869. — Healcy, M., The Fauna of the Napening beds 

 (Rhaetic) of Upper Burma. Palaeont. Indica, 1908, n.s., vol. ii., no. 4. — Ilolzapfel, E., Die 

 Molhisken der Aachener Kreide. Palaeontogr., 1887, vol. xxxiv. — Kitchin, F. L., The Jurassic 

 Fauna of Cutch. Laniellibranchiata. Palaeont. Indica, 1903, ser. ix., vol. iii., pt. 2. — Lcmbe, G., 

 Die Fauna von St. Cassian. Denkschr. Akad. Wiss. Wien, 1866, vol. xxv.—Pavlow, A., Enchaine- 

 ments des Aucelles et Aucellines du Cretace Russe. Nouv. Mem. Soc. Impi'r. Nat. Moscou, 1009, 

 vol. xvii. — Pompeckj, J. F., Uber Aucellen und Aucellen-ahnliche Formen. Neues Jahrb. f. 

 Min., 1901, Supi^lem. vol. xiv. — Quaas, A., Beitrag zur Kenntniss der Fauna der obersten 

 Kreidebilduug in der Lybischen Wtiste. Palaeontogr., 1902, vol. xxx. pt. 2 — StoUczka, F., 

 Cretaceous Fauna of Southern India. The Pelecypoda. Mem. Geol. Surv. East India, 1871, vol. 

 iii. — Waagen, L., Die Lamellibrancliiaten der Pachycardientuffe der Seiser Alp. Abh. Geol. 

 Reichsanst. Wien, 1907, vol. xviii. pt. 2. — Wood, H., Monograph of the Cretaceous Lanielli- 

 branchiata of England. Palaeont. Soc, 1899, vol. \m. — Zittcl, K. A, von. Die Bivalven der 

 Gosaugebilde. Denkschr. Akad. Wiss. Wien, 1865-66, vol. xxv. 



C. On Tertiary Forms : Androussov, N., Fossile und lebende Dreissensidae Eurasiens. Trav. 

 Soc. Imp. Sci. Nat. St-Petersb., sect, geol., 1897, 1903, vols, xx., xx\x.— Arnold, R., The 

 Tertiary and Quaternary Pectens of California. U.S. Geol. Surv. Profess. Papers, no. 47, 1906. — 

 BeUardi, L., and Sacco, F., I Molluschi terziari del Piemoute e della Liguria. Torino, 1872-1901. — 

 Chssnumn, M. , Catalogue illustre des coquilles fossiles de I'Eocene des environs de Paris. Fasc. 

 Ann. Soc. Malacol. de Belgique, 1888-89, vols, xxiii., xxiv.—Idem, and Fissaro, G., Iconographie 

 complete des coquilles fossiles de I'^^ocene des environs de Paris. Fasc. 1, Pelecypodes, 1904. — 

 DaU, W. H., Contributions to the Tertiary Fauna of Florida, i.-vi. Trans. Wagner Inst. Sci., 

 1890-1903, vol. ni.—Deperet, C, and Roman, F., Monographie des Pectinides neogenes de I'Europe 

 et des regions voisiues. Mem. Soc. Geol. France, 1902, vol. x.—Fontaniies, F., Les Molhisques 

 pliocenes de la Vallee de Rhone et du Roussillon. Lyons, 1879-83. — Gregorio, A., Monographie 

 de la faune eocenique de I'Alabama. Palermo, 1890. —^«m5, G. D., Bull. Amer. Palaeont., 

 1895-97, vols, i.-iv. — Hoernes, M., Die fossilen MoUusken des Tertiiirbeckens von Wien. Abhandl. 

 Geol. Reichsanst. Wien, 1870, vol. iv. — Koencn, A. von, Das norddeutsche Unter-Oligocan und 

 seine Mollusken-Fauna. Abhandl. Geol. Spezialkarte Preussen, 1889-93, vol. x. — 02)penheim, 

 P., Zur Kenntnis alttertiiirer Fauuen in Agyjiten. Palaeontogr., 1903-6, vol. xxx. pt. 3. — 

 Ortmann, A. E., Families and Genera of the Najades. Ann. Carnegie Mus., 1912, vol. viii. no. 

 x. — Sandberger, F., Die Conchylien des Mainzer Beckens, 1860-63. — Idem, Die Land- und 

 Siisswasser - Conchylien der Vorwelt. Wiesbaden, 1875. — Schafer, F. X., Die Bivalven der 

 Miocanbildungen von Eggenburg. Abh. Geol. Reichsanst. Wien, i910, vol. xxii. — Simpson, 0. J., 

 Synopsis of the Naiades or Pearly Fresh-water Mussels. Proc. U.S. Nat. Mus., 1900, vol. xxii., no. 

 1205. — Ugolini, R., Monografia dei Pettinidi neogenici della Sardegna. Palaeont. Ital. 1906-7, 

 vols, xii., xiii. — Wood, S., Monograph of the Eocene Bivalves of England. Palaeontogr. Soc, 

 1861-71. 



