|=;^:;:':|^r';' ::!;;::- iåmMr ^■toi'!::i:;:^':' m^ø^?:^ Wi'!M ::•;•:. ,';■! Vi': mê É^i;.^: Ml"'«'';.!-/,! 'Il' É;lié^ « : "iW iRt. .vTi 'II" ■'T^'ty'i!r..!|f--i; ■|^::'i.SI^;' B:'r!ï-:l - ■';' ■■ ■■''l-'i ■ ■ PII ■■'■ 'i V.'- ■,'.■■ ^^lÆ':::',::;;:':^: . !..■ ' '' ■'' : ' DET KONGELIGE DANSKE VIDENSKABERNES SELSKABS SKRIFTER SYVENDE RÆKKE MTURVIDENSKABELIG OG MATIEMATISK AFDELING FEMTE BIND •^•hS-- KØBENHAVN BIANCO LUNOS BOGTRYKKERI 1910 INDHOLD Side Fortegnelse over Selskabets Medlemmer September 1910 V 1. Nielsen, N.: Recherches sur quelques généralisations d'une identité intégrale d'Abel 1 — 37 2. Petersen, Henning Eiler: Danske Arter af Slægten Ceramium (Roth) Lyngbje. Med 9 Figurer i Teksten og 7 Tavler. Avec un résumé en français 39— 96 3. Lynge, Herman: The Danish Expedition to Siara 1899—1900. IV. Marine Laraellibranchiata. With 5 plates and a map 97—299 4. Ratllbnn, Mary J. (Washington D. C): The Danish Expedition to Siam 1899 — 1900. V. Bra- chyura. With 2 plates and a map 301—368 3)ûC>^^ FORTEGNELSE OVER DET KtlNGELIHIi DANSKE VIDENSKABERNES SELSKABS MEDLEMSIER September 1910 Protektor : Hans Majestæt Kongen. Præsident: Vilh. Thomsen. Foniiaiid for deu hist.-fllos. Klasse : L. F. A. Wimmer. Formaud for den naturv.-math. Klasse : S. M. Jørgensen. Sekretær: H. G. Zeuthen. Redakter: J. L. Heiberg. Kasserer: W. L. Johannsen. Kasse-Kommissionei]. P. E. Holm. T. N. Thiele. J. P. Gram. H. Høffding. Revisorer. H. Valentiner. O. T. Christensen. Kommissionen for Registrering af litterære Kilder til dansk Historie i Udlandet. Joh. Steenstmp. J. A. Fridericia. H. O. Lange. Udvalg for den internationale Katalog over naturvidenskabelige Arbejder. H. G. Zeidhen. S. M. Jørgensen. C. Christiansen. Fr. V. A. Meinert. Chr. Bohr. L. Kolderup Rosenvinge. Medlemmer af det staaeude Udvalg for den internationale Association af Akademier. H. G. Zeuthen. J. L. Heiberg. iDdeniandske Medlemmer. Holm, Peter Edvard, Dr. pliil., fh. Professor i Historie ved Københavns universitet, Stor- kors af Danebrog og Danebrogsmand, Kommandør af St. Olafsordenen. Rørdam, Holger Frederik, Dr. pliil., Sognepræst i Lyngby, Ridder af Danebrog og Danebrogsmand. Zeuthen, Hieronyimis Georg, Dr. pliil. & math., fh. Professor i Mathematik ved Københavns Universitet og den polytekniske Læreanstalt, Kommandør af Danebrog og Dane- brogsmand, Kommandør af Nordstjernen, Selskabets Sekretær. Jørgensen, Sofus Mads, Dr. phil., fh. Professor i Kemi ved Københavns Universitet og den polytekniske Læreanstalt, Kommandør af Danebrog og Danebrogsmand , Formand i Selskabets naturvidenskabelig-mathematiske Klasse. Christiansen, Christian, Dr. med., Professor i Fysik ved Københavns Universitet og den polytekniske Læreanstalt, Kommandør af Danebrog og Danebrogsmand. Krabbe, Harald, Dr. med., fh. Professor i Anatomi ved den Kgl. Veterinær- og Landbohøj- skole, Kommandør af Danebrog og Dannebrogsmand, Ridder af St. Olafsordenen. Thomsen, Vilhelm. Ludvig Peter, Dr. phil.. Professor i sammenlignende Sprogvidenskab ved Københavns Universitet, Storkors af Danebrog og Danebrogsmand, Kommandør af den preussiske Røde Ørns Orden, dekoreret med Forljenstmedaillen i Guld, Selskabets Præsident. Wimmer, Ludvig Frands Adalbert, Dr. phil. & litt., fh. Professor i de nordiske Sprog ved Københavns Universitet, Storkors af Danebrog og Danebrogsmand, dekoreret med Forljenstmedaillen i Guld, Formand i Selskabets historisk-fllosoQske Klasse. Topsøe, Haldor Frederik Axel, Dr. phil., Direktør for Arbejds- og Fabriktilsynet, Kommandør af Danebrog og Danebrogsmand, dekoreret med Forljenstmedaillen i Guld. Warm^ing , Johannes Eugenius Bülow, Dr. phil., Professor i Botanik ved Københavns Universitet, Kommandør af Danebrog og Danebrogsmand, Kommandør af den slor- brilanniske Victoriaorden, Ridder af den brasilianske Roseorden. VIII Thiele, Thorvald Nikolai, Dr. phil., fh. Professor i Astronomi ved Københavns Universitet. Meinert, Frederik Vilhelm August, Dr. phil., I'ii. Inspektor ved universitetets zoologiske Museum, Ridder af Danebrog og Danebrogsmand. Goos, August Herman Ferdinand Carl, Dr. jur., Gehejme-Etatsraad, extraord. Assessor i Højesteret, Storkors af Danebrog og Danebrogsmand, dekoreret med Majestæ- ternes Guldbryllups-Erindringstegn, Storkors af den belgiske Leopoldsordeii, Kom- mandør af den russiske St. Annaorden, Nordstjernen og den italienske Kroneorden. Steenstrup, Johannes Christopher Hagemann Reinhardt, Dr. jur. & phil., Professor Rostgardianus i nordisk Historie og Antikviteter ved Københavns universitet. Kommandør af Danebrog og Danebrogsmand, Kommandør af Nordstjernen, Ridder af Æreslegionen. Gertz, Martin Clarentius, Dr. pliil.. Professor i klassisk Filologi ved Københavns Univer- sitet, Kommandør af Danebrog og Danebrogsmand, Kommandør af den italienske Kroneorden og af Nordstjernen. Heiberg, Johan Ludvig, Dr. phil., litt. & sc, Professor i klassisk Filologi ved Københavns Universitet, Ridder af Danebrog; Selskabets Redaktør. Høffding, Harald, Dr. phil., jur., se. & litt.. Professor i Filosofi ved Københavns Universitet, Ridder af Danebrog og Danebrogsmand, Kommandør af St. Olafs Ordenen og Nord- stjernen, Officier de l'instruction publique. Krom.an, Kristian Frederik Vilhelm, Dr. phil.. Professor i Filosofi ved Københavns universitet, Ridder af Danebrog. Müller, Peter Erasmus, Dr. phil.. Kammerherre, Hofjægermester, Overførster for anden Inspektion , Overinspektør for Sorø Akademis Skove , Kommandør af Danebrog og Danebrogsmand, dekoreret med Majestæternes Guldbryllups-Erindringstegn, Kom- mandør af St. Olafsordenen, af den russiske St. Annaorden, af den spanske Carl Ill's Orden, af den græske Frelserorden og af den preussiske Røde Ørns Orden. Bohr, Christian Harald Lauritz Peter Emil, Dr. med. & se, Professor i Fysiologi ved Københavns Universitet, Ridder af Danebrog og Danebrogsmand. Gram, Jørgen Pedersen, Dr. phil.. Formand i Forsikringsraadet, Direktør ved Forsikrings- selskabet "Skjold" i København, Ridder af Danebrog og af St. Olafsordenen. Valenfiner, Herman, Dr. phil., Direktør for Forsikringsselskabet «Dan» i København. Erslev, Kristian Sofus August, Dr. phil.. Professor i Historie ved Københavns Universitet, Ridder af Danebrog og Danebrogsmand. Fridericia, Julius Albert, Dr. phil.. Professor i Historie ved Københavns Universitet, Ridder af Danebrog. IX ujILIBRAR Christensen, Odin Tidemand, Dr. phil., Professor i Kemi ved den kgl. Veterinær- og V^i^-*-*^ Landbohøjskole, Ridder af Danebrog og Danebrogsmand, Ridder af St. Olafsordenen. "^ » -- Boas, Johan Erik Vesti, Dr. phil. , Professor i Zoologi ved den kgl. Veterinær- og Landbohøjskole, Ridder af Danebrog og St. Olafsordenen. Petersen, Otto Georg, Dr. phil., Professor i Botanik ved den kgl. Veterinær- og Landbo- højskole, Ridder af Danebrog. Prytz, Peter Kristian, Professor i Fysik ved den polytekniske Læreanstalt, Riîlder af Danebrog. Salomonsen, Carl Julius, Dr. med. & se. Professor i Pathologi ved Københavns Universitet, Direktør for Statens Serum-institut, Kommandør af Danebrog og Danebrogsmand, Kommandør af den preussiske Kroneorden, af den russiske St. Stanislausorden og af den svenske Vasaorden, Ridder af Nordstjernen og af St. Olafsordenen, Officier de l'instruction publique. Sørensen, William, Dr. phil., Privatlærer. Møller, Hermann, Dr. phil., Professor i germansk Filologi ved Københavns universitet, Ridder af Danebrog. Pechi'de, Carl Frederik, Observator ved Universitetels astronomiske Observatorium, Ridder af den russiske St. Annaorden. Jonsson, Finmir, Dr. phil., Professor extraordinarius i nordisk Filologi ved Københavns universitet. Ridder af Danebrog. Müller, Sophus Otto, Dr. phil.. Direktør for Nationalmuseets første Afdeling, Ridder af Danebrog og Danebrogsmand, Ridder af Æreslegionen. Bergh, Rudolph Sophus, Dr. phil., fh. Docent i Histologi ved Københavns Universitet. Johannsen, Wilhelm Ludvig, Dr. med.. Professor i Plantefysiologi ved Københavns Uni- versitet, Ridder af Dannebrog, Selskabets Kasserer. Jespersen, Jens Otto Harry, Dr. phil., Professor i engelsk Sprog og Litteratur ved Københavns Universitet, Ridder af Danebrog. Nyrop, Kristoffer, Dr. phil., Professor i romansk Sprog og Litteratur ved Københavns Universitet , Ridder af Danebrog og Danebrogsmand , Officier de l'instruction publique. Ridder af den italienske Kroneorden og af Æreslegionen, dekoreret med rumænsk Fortjenstmedaille i Guld. Bang, Bernhard Latirits Frederik, Dr. med., Veterinærfysikus, Professor i Veterinær- Lægevidenskab ved den kgl. Veterinær- og Landbohøjskole ved København , Kom- mandør af Danebrog og Danebrogsmand, Kommandør af Nordstjernen, Kommandør af St. Olafsordenen. Juel, Christian Sophus, Dr. pliil., Professor i Mathematik ved den polytekniske Læreanstalt i København. Buhl, Frantz Peter William, Dr. phil. & theol., Professor i semitisk-orientaisk Filologi ved Københavns Universitet, Ridder af Danebrog og Danebrogsmand, Ridder af Nordstjernen og af Kongeriget Sachsens Civil Fortjeneste Orden. Kålund, Peter Erasmus Kristian, Dr. phil., Ribliotekar ved den Arnamagnæanske ■ Haandskriftsamling paa Universitetsbiblioteket i København, Ridder af Danebrog. Rosenvinge, Janus Laurits Andreas Kolderup, Dr. phil.. Docent i Botanik ved Københavns Universitet. Troels-Lund, Troels Frederik, Dr. phil., Professor, Ordens-Historiograf, Kommandør af Danebrog og Danebrogsmand, Ridder af den græske Frelserorden. Dreyer, Johan Ludvig Emil, Dr. phil.. Director of the Armagh Observatory, Irland, Ridder af Danebrog. Jungersen, Hector Frederik Estrup, Dr. phil. & se. Professor i Zoologi ved Københavns universitet, Ridder af Danebrog. Levinsen, Georg Marius Reinald, Inspektor ved det zoologiske Museum i København, Ridder af Danebrog. Lehmann, Alfred Georg Ludvig, Dr. phil.. Professor i experimental Psykologi ved Køben- havns Universitet. Ruhin, Marcus, Generaldirektør for Skattevæsenet, Historiker, Kommandør af Danebrog og Danebrogsmand, Storkomtur af den meklenburgske Grif-Orden, Kommandør af den russiske St. Stanilausorden. Raunkiær, Christen, Mag. se. Docent i Botanik ved Københavns Universitet. Steenstrup, Knud Johannes Vogelius, Dr. phil.. Geolog, Ridder af Danebrog. Drachmann, Anders Bjørn, Dr. phil.. Professor i klassisk Filologi ved Københavns Universitet. Hude, Karl, Dr. phil.. Rektor ved Frederiksborg lærde Skole. Christensen, Anders Christian, Professor i r(emi ved den farmaceutiske Læreanstalt i København. Henriques, Valdemar, Dr. med. , Professor i Dyrefysiologi ved den kgl. Veterinær- og Landbohøjskole ved København. Jensen, Carl Oluf, Dr. med., Professor i almindelig Pathologi og pathologisk Anatomi ved den kgl. Veterinær- og Landbohøjskole ved København, Ridder af Danebrog, af St. Olafsordenen og af Nordstjerneordenen. XI Ussing, Niels Viggo, Dr. pliil., Professor i Mineralogi ved Købenliavns Universitet, Ridder af Danebrog. Pedersen, Holger, Dr. phil., Professor ekslr. i slavisi; Filologi og sammenlignende Sprog- videnskab ved Københavns Universitet. Lange, Hans Ostenfeldt, Overbibliotekar ved det kongelige Bibliotek i København, Ridder af Danebrog og St. Olafsordenen. Sørensen, Søren Peter Lauritz, Dr. phil., Professor, Forstander for Carlsberg-Labora- toriets kemiske Afdeling, København. Olrik, Axel, Dr. phi!., Docent i nordiske Folkeminder ved Københavns Universitet, For- stander for Dansk Folkemindesamling. Jensen, Johan Ludvig William Valdemar, Telefoningeniør, Ridder af Danebrog. Andersen, Dines, Dr. phil.. Professor i indisk-østerlandsk Filologi ved Københavns Uni- versitet. Knudsen, Martin, Docent i Fysik ved Københavns universitet. Thoroddsen, Thorvaldur, Dr. phil., Professor, Geolog, Ridder af Danebrog. Olsen, Björn Magnusson, Dr. phil., Professor, fh. Rektor ved Reykjavik lærde Skole, Ridder af Danebrog og Danebrogsmand. Madsen, Thorvald Johannes Marius, Dr. med.. Direktør for Statens Seruminstitnt, Ridder af Danebrog, af den preussiske Røde ørns Orden og af den svenske Nordstjerne- orden. Winge, Adolph Herluf, Viceinspektør ved Kßbenhavns universitets zoologiske Museum. Udenlandske Medlemmer. Hooker, S\r Joseph Dalton, M.D., D. C. L., LL.D., fli. Direktør for den Kongelige Botaniske Have 1 Kew, The Camp, Sunningdale, Berkshire. Lord Avebury, John Lubbock, D. C. L., LL. D., Præsident for Society of Antiquaries i London, High Elms Down, Kent. Delisle, Leopold -Victor, Medlem af det franske Institut, Direktør for Bibliothèque Nationale i Paris, Kommandør af Danebrog. Malmström, Carl Gustaf, Dr. phil., fh. kgl. svensk Rigsarkivar, Stockholm. Retzius, Magnus Gustav, Dr. med. & phil., fh. Professor i Histologi ved det Karolinske mediko-kirurgiske Institut i Stockholm. Conze, Alexander Christian Leopold, Dr. phil.. Professor, Generalsekretær ved Direk- tionen for det tyske arkæologiske Institut, Berlin. Meyer, Marie-Paul-Hyacinfhe , Medlem af det franske Institut, Direktør for École des Chartes, Professor i sydeuropæiske Sprog og Litteraturer ved Collège de France, Paris. Sievers, Eduard, Dr. phil.. Professor i germansk Filologi ved Lniversitetet i Leipzig. Wnndt, Wilhelm, Dr. phil., Professor i Filosofi ved universitetet i Leipzig. Leffler, Gösta Mittag-, Dr. phil., Professor i Mathematik ved Højskolen i Stockholm, Kommandør af Danebrog. Nathorst, Alfred Gabriel, Dr. phil.. Professor, Intendant ved Riksmuseets botanisk-palæ- ontologiske Afdeling i Stockholm. Darboiiæ, Gaston, livsvarig Sekretær ved Académie des Sciences, Professor i Mathematik ved Faculté des sciences i Paris. Sars, Georg Ossian, Professor i Zoologi ved Universitetet i Kristiania. Tieghem,, Philippe van. Medlem af det franske Institut, Professor i Botanik ved Muséum d'histoire naturelle i Paris. d' Ancona, Alessandro, Professor i italiensk Litteratur ved Universitetet i Pisa. Bréal, Mi chel-Jides- Alfred, Medlem af det franske Institut, Professor i sammenlignende Sprogvidenskab ved Collège de France, Paris. Brefeld, Oscar, Dr. phil.. Professor i Botanik, Direktør for det botaniske Institut i Breslau. XIII Tegner, Esaias Henrik Vilhelm, l)r. phil. & tlieol., Professor i østerlandske Sprog ved Universitetet i Lund. Brøgger, Valdemar Christofer, Professor i Mineralogi og Geologi ved Universitetet i Kristiania, Ridder af Danebrog. Ham,marsten, Olof, Dr. med. & phil., Professor i medicinsli og fysiologisk Kemi ved Uni- versitetet i Upsala. Klein, Felix, Dr. phil., Professor i Mathematik ved Universitetet i Göttingen. Schwartz, Carl Hermann Amandtis, Dr. phil., Professor i Mathematik ved Universitetet i Berlin. Storm, Johan Frederik Breda, LL.D., Professor i romansk og engelsk Filologi ved Universitetet i Kristiania. Comparetti, Domenico, fhv. Professor i Græsk, Firenze. Schwendener, Simon, Dr. phil., Professor i Botanik ved Universitetet i Berlin. Söderwall, Knut Frederik, Dr. phil.. Professor i nordiske Sprog ved Universitetet i Lund. Dörpfeld, Wilhehn, Professor, Dr. phil., første Sekretær ved det tyske arkæologiske In- stitut i Athen. Pfeffer, Wilhelm, Dr. phil., Professor i Botanik ved Universitetet i Leipzig. Fries, Theodorns Magnus, Dr. phil., fh. Professor i Botanik ved Universitetet og Direktør for dets botaniske Have i Upsala. Wittrock, Veit Brecher, Dr. phil. , Professor Bergianus og Intendant ved Rigsmuseet i Stockholm. Backlund, Albert Victor, Dr. phil.. Professor i Fysik ved Universitetet i Lund. Hittorf, Wilhelm, Dr. phil.. Professor i Fysik ved Universitetet i Munster. Lord Kayleigh, John William Strutt, Dr. phil., D. C. L. , Professor i Fysik ved Royal Institution, London. Wilamowitz-Moellendorff, Ulrich von, Dr. phil.. Professor' i klassisk Filologi ved Uni- versitetet i Berlin. Collett, Bobert, Professor i Zoologi ved Universitetet i Kristiania. Duner, Nils Christoffer, Dr. phil.. Professor i Astronomi ved Universitetet i Upsala. Schmoller, Gtistav, Dr. phil. , Historiker, Professor i Statsvidenskaberne ved Universitetet i Berlin. Hertwig, Oscar, Dr. med.. Professor i sammenlignende Anatomi og Direktør for det 2det anatomisk-biologiske Institut ved Universitetet i Berlin. Strasburger, Eduard, Dr. phil., Professor i Botanik ved Universitetet i Bonn. XiV Fouillée, Alfred, Medlem al' det franske Institut, fh. Professor i Filosofi, Paris. Dastre, Albert- Jules- Frank, Professor i Fysiologi ved la Faculté des Sciences, Paris. Picard, Charles- Emile , Medlem af det franske Institut, Professor i Mathematik ved la Faculté des Sciences, Paris. Poincaré, Henri, Medlem af det franske Institut, Professor i Mathematik ved la Faculté des Sciences, Paris. Ehrlich, Paul, Dr. med.. Direktør for det kgl. preussiske Institut for experimentel Therapi i Frankfurt a. M., Kommandør af Danebrog. Helniert, Friedrich Robert, Dr. phil. , Professor ved Universitetet i Berlin, Direktør for det geodætiske Institut og den internationale Gradmaalings Bureau i Potsdam, Kommandør af Danebrog. Henry, Louis, Professor i Kemi ved universitetet i Louvain. Treub, Melchior, Dr. phi!., fh. Bestyrer af den botaniske Have i Buitenzorg ved Batavia. Vries, Hugo de, Dr. phil.. Professor i Botanik ved Universitetet i Amsterdam. Pettersson, Otto, Dr. phil.. Professor i Kemi ved Stockholms Højskole, Kommandør af Danebrog. Brugmann, Friedrich Karl, Dr. phil., Professor i indo-germansk Filologi ved Universi- tetet i Leipzig. Engler, Adolph, Dr. phil.. Professor i Botanik ved Universitetet i Berlin. Goebel, Karl, Dr. phil., Professor i Botanik ved Universitetet i München. Ho/f, Jacob Heinrich vant, Dr. phil.. Professor i Kemi ved Universitetet i Berlin Ramsag, Sir William, Professor i Kemi ved University College i London. Hasselberg, Klas Bernhard, Professor, Fysiker ved Vetenskapsakademien i Stockholm. Diels, Hermann, Dr. phil.. Professor i klassisk Filologi ved Universitetet i Berlin. Gomperz, Theodor, Dr. phil., fh. Professor i klassisk Filologi ved Universitetet i Wien. Mohn, H, Professor i Meteorologi ved Universitetet i Kristiania. Pavlov, Ivan Petrovic, Professor 1 Fysiologi ved det kejserlige militærmedicinske Akademi i St. Petersborg. Rhgs Davids, T. TV., Professor i Pali og buddhistisk Litteratur ved University College i London. Sweet, Henry, Dr. phil., Oxford. Arrhenius, Svante, Dr. phil., Professor i Fysik ved Højskolen i Stockholm, Kommandør af Danebrog. Kock, Axel, Dr. phil.. Professor i nordiske Sprog ved Universitetet i Lund. ^^ (tu L I B R A R ^ LU Noreen, Adolf Gotthardt, Dr. phil., Professor i de nordiske Sprog ved Universitetet i Lpsala. \^'^i^>^Aî3'^ ^^.^ Ilt N Torp, Alf, Dr. phil., Professor i Sansl"«- K0BENHAVN BIANCO LUNOS BOGTRYKKEKI 1907 Introduction. La démonstration rigoureuse que C. Neumann') a donnée pour l'existence des séries de carrés des fonctions cylindriques est extrêmement élégante. En effet, en appliquant sa formule intégrale (J'\x))'' = - • \'J-'\2xcos — 2' ^^^ l'intégrale eulérienne de première espèce \-(cos^)«(sin^)M. = 2 • J-t^'a ' (') OÙ il faut admettre ^H(a) > — 1, ïK(b) — 1, donnera immédiatement pour F(x) cette série de puissances qui a également son raj'on de convergence égal à r. Appliquons ensuite l'autre formule eulérienne r{a)r{l-a) = .--, (5) ^ ' sm an- nous aurons par le même procédé: \^Fixsin^,UsinMt9^rd^ = 3-^, "X TT^' «.'0 '^ s = il I d'où, en vertu de (1) et (2), cette identité intégrale: 2^^ • f<^) = ^T7('^•c-•os^^sinç'.) (.rsinç'.) {ty^f (sin ,sf'cl,fd^' , (6) où il faut admettre généralement ^ > '^{p) > ~ o" 6^ Cela posé, il est facile de voir que la formule de Cauchy l {cos - 1' (7) 2"+'r(q:-^f i)r("^'+i)' nous conduira à une identité analogue à (6). A cet effet, mettons pour abréger: = f/"" G(x} = Y f(xcos(f) (cosK(!/) > — 1; (8) nous aurons tout d'abord, en vertu de (7), pour G (a) la série de puissances ' "fà 2—' rt-±f+-^+ 1) r{^--i+^+ 1)' ^ ^ qui a aussi son rayon de convergence égal à r. Appliquons ensuite la formule (3), il résulte : s — X u + s + I 7;(.i-sin2ç/0(.rsin2çA)^+'(cotvAy'VçA == ^ '^ ^^J+l ., = (1 ' ■■+■ d'où finalement cette autre identité intégrale : /■(.r) = • Dx \"\7(.rcos^sin2^)(cosîf)(xsin2^)''+'(cot^)'"dçcd^, (10) où il faut supposer généralement ^TÎ(v) > — 1, 'iR(v — p) > ^ — 2. Or, il est très facile de généraliser beaucoup les deux formules (6) et (10) que nous venons de démontrer pour une fonction qui est supposée holomorphe aux environs de l'origine. A cet effet, supposons que f{x) soit développable en série comme suit: f{x) = a„pu(x) + aiP,(x-) + . . . -f anpn(x) + • • -, (H) où les fonctions p,(x) sont holomorphes aux environs de l'origine, puis supposons que la série (11) soit uniformément convergente dans un domaine du plan des a- qui contient le point x = 0; des théorèmes très connus concernant la diflërentiation et l'intégration terme à terme d'une série infinie') montreront que les deux formules susdites sont également applicables à cette fonction plus générale. Nos deux formules en question (6) et (10) sont applicables à des fonctions beaucoup plus générales encore; cependant le cas susdit suffit pour nos recherches suivantes. ') U. DiNi : Grundlagen für eine Theorie der Kiinktionen einer veränderliclien reellen Grösse, pp. 523, 528; 1892. Posons y = ^ = O, les deux formules susdites deviennenl évidemment iden- tiques; ce cas particulier est dû à Abel'), tandis que la formule plus générale (6) a été trouvée par M. N. de Sonin-). Quant à la formule (10), elle est de moi; dans mon Traité des fonctions cylindriques^} je n'ai donné que le cas particulier qui correspond à v = 0. Dans ce qui suit nous avons souvent besoin de diviser en deux parties chacune des identités que nous venons de développer. A cet effet, posons d'abord: F{.v) ^\'f{.vc.os)(xs\n,/>){igø''dç)d^, (13) nous aurons de même inversement: ■tiz f{x) = -?-, • DÅ ' G (x sin 2 if) {x sin 2 ^)' "*" ' (col ipf d^p . (13 bis) § 2. Transformation d'une série de fonctions P" "(.»). Comme première application de l'identité intégrale § 1, (6), nous avons à trans- former la série de fonctions ultrasphériques ') s = x f{ax) = r{v) ■ ^ (v + 2s) A^' ''\a)P'' -\x) (1) ï = 0 qui est supposée convergente sous les conditions suivantes: A. x doit être situé dans un domaine K (à une ou à deux dimensions) dans le plan des x qui contient le point x = 0. ') Journal de Grelle, t. 1, p. 155; 182G. Œuvres 1. 1, p. 99. Abel donne, sous une autre forme, notre formule (6) dans le cas particulier, où p est supposé réel, de sorte que ^ > /o > — Tit tandis que M. de SoNiN indique la formule générale. 2) Mathematische Annalen, t. 16, p. 48; 1880. Acta Mathematica, t. 4, p. 171; 1884. ') Handbuch der Theorie der Zylinderfunktionen, p. .380; 1904. ') Voir mon mémoire intitulé: Recherches sur les fonctions sphériques, p. 47 (285). Mém. de l'Acad. Koyale de Danemark, 7« série, t. 2; 1900. 8 B. a doit être situé dans un domaine L fà une on à deux dimensions^ dans le plan des a qui contient le point a = 0. C. La convergence dans le domaine L doit être uniforme. Cela posé, mettons dans (1) a; cos ^ au lieu de x et « sin ^A au lieu de «, il résulte cette autre formule: s = X f(axsin(pcos(p)=I\v)'y (u ^2s)A'' -\asin(/>)P''-'(xcos^), (2) s = 0 OÙ la série infinie qui figure au second membre de (2) est uniformément convergente, si nous faisons varier dans l'intervalle de 0 à ;r : 2 (les valeurs extrêmes 0 et ;r : 2 y comptées) les deux variables réelles 9Î d") > — g ' '^ ^^^ évident que l'opération § 1, (6) est applicable terme à terme à la série infinie qui figure au second membre de (2). Quant au résultat ainsi obtenu, il s'agit de déterminer tout d'abord l'intégrale définie j _ y pv, a "(a; cos f) (sin ^fd^ . (3) A cet effet, introduisons l'expression ordinaire de P"' '"(a'), savoir: s = n ^-^^ - y(0 ^^ sl(2n-2s)! ^^^^ ' ^*' la formule § 1, (4) donnera immédiatement: , ^1^ + ï) V {-iyr(2n-s + u)r(n-s+\) ^^ ^^ 2r(.) 'f^, s! r(2n-2s + l)r(n-s + /> + l)"^ appliquons maintenant la formule eulérienne Vn r(a) = r(^±^) rg + 1) • 2" - ', (5) il résulte après une légère transformation : 2r(.)/> + l) • n! où F désigne la série hypergéométrique ordinaire. '- 2r(.)/> + l).n! ■n'^ + n, -n,p^l,x^~) (6) Cela posé, mcUons pour abréger: (7) nous aurons ce théorème général : I. La série de fonctions nltrasphériqnes { 1 ) peut être transformée en une série de fonctions hypergéométriques comme suit: _^^ r(p + l) cos p 71 ' ^""^' r{p + 1) 1/ ri -L 1 ^ = ^ où il faut admettre ^ > ''^{p) > — ^, tandis que les coefficients '^H se déterminent à l'aide de (7); les deux séries {D et (8) sont en même tenips convergentes ou divergentes. Quant au champ commun de convergence des deux séries (1) el (8), il est évident que (8) est convergente où l'est (1). Or, prenons pour point de départ (8), puis mettons-y x sin ç/' au lieu de æ et a sin y: au lieu de a, l'identité S 1, (6) nous conduira immédiatement à la série de fonctions uUrasphéricjues (1). Telle est la démonstration complète de notre théorème susdit. § 3. Application aux séries de C. Neumann. Supposons particulièrement que la fonction f[x) que nous venons d'étudier dans le § 2 soit paire et holomorphe aux environs du point x= 0, de sorte que la série de puissances correspondante /•(.r) = ao + a.x^ + asx* -r ... -La„.r=^«+ ... (D ait le rayon de convergence ;■, puis supposons a < r; la série de fonctions ultra- sphériques § 2, (1) deviendra une série neumannienne et elle est certainement con- vergente à l'intérieur de l'ellipse ^ ^ -' =1, X = ç -- iy] (2) fâ (^) 1 qui a son centre dans l'origine et ses foyers dans les deux points (^ 1, 0); dans ce qui suit nous désignons par E{r,a) l'aire située à l'intérieur de l'ellipse (2)')- Le coefficient général A"' ^ "-"(«) de la série neumannienne (|ui représente la série de puissances f(ax) se détermine par l'expression-) ') A la p. 53 |291) de mon mémoire cité p. 7 j ai indiqué une équation fausse de l'ellipse de conver- gence (2). En effet, l'ellipse que j'ai indiquée est plus petite que (2). La raison île cette équation inexacte est à chercher dans le théorème démontré p. 32 (270) du mémoire susdit. -1 Recherches sur les fonctions sphériques, p. 17 (285). I> K 11 Vidi'iiNK.Sclsk. Ski-.. 7. U:i-kkc, luiliirviilrnsk. OB ilKitheili. Alcl. V. 1. 2 10^ A.-n^a)^^ ^, - . (2) , (3) s = (1 ce qui donnera pour 51" '" "(«1, en vertu de S 2, (7) et des formules eulériennes S 1,(3) et S 2, (5), cette expression analogue: '' ^"' ~ „II/- ^ s! nH-2n^s+l) «"+-'»" • '*' Appliquons ensuite la formule eulérieune S 1,(5), puis mettons pour abréger: ^ ''• r(o+l) ^ /•(u+2n + s+l) l s ;"--'" + -^-' " ' '•^' il est très facile de démontrer cet autie théorème général: II. Pour la série de puissances (1) nous obtenons ce développement en série de fonctions hypergéoniétriques : f[ax) -^ ^ (—\)\^-^2s)B''f-'[a)-F[u + s,-s,p+\,x-i), (6) s = n où les deux paramètres u et /> sont des quantités finies quelconques différentes des négatifs entiers , tandis que le coefficient général B se détermine à laide de (5). La série (6) est convergente où l'est la série neumannienne correspondante, savoir dans le domaine E (r, a). En etî'et , il ne nous reste plus qu'à étudier les conditions susdites des deux ])aramètres j/ et p. Quant à 1/, la condition susdite est évidente par ce qu'elle est nécessaire pour l'existence de la série neumannienne elle-même. Etudions maintenant le paramètre p\ la formule (6) est certainement démontrée pourvu que ,, > '^(p) > —g- Introduisons ensuite cette autre série de puissances; S = U 1 {p + l)r(s + ^ qui à le même rayon de convergence que la série donnée /'(.r) elle-même, nous aurons, en vertu de § 1, (3): f{x) = Vg{xcos,p){sm,pfPd,f, )H{p) > -l- (7) Cela po.sé, étudions la série neumannienne correspondante g («.r) = ^ iu f 2s) Bja) P" -''(x) , (8) n qui esl val;il)lu dans le domaine E (r, a): les deux idenlilés (7) et ,^ 2, (6) nous con- duiront inunédialenienl à la formule (6), de sorte que cette dernière formule est applicable pour iR{p} > — ^. Nous nous bornerons ici à ce développement , parce que la démonstration de |6) pour ^K (p) < — ,y sera assez pénible à cause des valeurs limites qu'il faut introduire. § 4. Series de fonctions F(y + w, —n,p^\, x). Étudions maintenant plus amplement la série §3, (6). A cet effet, posons .r^ -^ y, «'- =- /J; il s'agit tout d'abord de déterminer ce que deviendra l'ellipse E {r, u) ayant l'équation S 3, (2), savoir, en posant r- = p: ml \ß\ posons ensuite y = Ci h ir^i, il résulte c. = ç'-r, îf, = 2$n, (2) de sorte qu'il ne nous reste qu'à éliminer de (1) et (2) les deux coordinées $ et ', ce qui s'effectuera sans peine; nous aurons par là l'équation suivante: (^^ - 2)" rj,"- _ qui représente une ellipse ayant son centre en (-., , O) et ses foyers aux deux points (0, 0) et (1, 0), tandis (jue son plus grand axe est égal à p : ß\ — — . Dans ce qui suit nous désignons par @ (p, ß] l'aire située à l'intérieur de l'ellipse (3). Supposons maintenant ([ue la série de puissances f(x) --= a„ + a, a.' - a^x''^ + . . . + a„.x"' + . . . (4) ait son rayon de convergence égal à r, puis mettons pour abréger: ^ """r(,..+ l) ^ r(. + 2n+s+l) l s j"""»" ' '^' ' .s = Il nous aurons cet autre théorème général : III. Pour la série de puissances (4) nous obtenons ce développement en série de fonctions hijpergéométriques : s -^ j: fiax) =^ {— D'il' + '2s) A'-'' '{a) F{',+s,~s,p+l,x), (6) s = Il 12 où les paramètres i^ el p ne doivent pas être égaux à un négatif entier, mais étant dn reste comptèfement (uhitraires. Le coefficient général A se détermine à l'aide de (âl, ('/ ta série (Ü) est convergente dans le domaine (i (r, a). La série (6), ([ui est certainement nouvelle, est évidemment de même nature (jue les séries neumanniennes. En effet, les deux formules (6) el S '2, (1) sont des identités formelles ([ui per- mettent de déduire formellement les séries de fonctions P ou F en développant chacune des puissances qui figurent aux premiers membres des formules susdites. Mais d'un autre coté, les séries ainsi obtenues et la série de puissances donnée ne possèdent pas le même champ de convergence. Considérons par exemple les trois fonctions particulières (jui sont luules les trois holomorphes aux environs du point x = 0; les ellipses de convergence des séries neumanniennes correspondantes ont , pour « = 1 , les équations — J- î- = 1 ?- -I- / - = 1 J_ _1_ -2— = 1 tandis que les séries tirées de (6) en mettant « = 1 sont convergentes à l'intérieur des ellipses suivantes: Comme applications directes de (6), considérons d'abord la formule élémentaire ^.n _ r{p+n+l) _ y /;n _ 1^ + 25) /> + s) _ S = (l qui est valable dans toute l'étendue du plan des a-, en second lieu la fonction cylindrique de première espèce donnera ce développement très connu'): \VaxJ \Va) f^, s! / (^ + 1) applicable pour des valeurs finies quelconques de .v et de «. ') Haudbucli der Theorie der Zylinderfuuktioiien, p. 275; 1904. u-4-s,-s,,o+l,.T) (8) 13 ,^ 5. Series des fonctions inypergeométriques générales. Comme une application plus imporlanlu du théorème III, nous tirons directe- ment de S 4, (6), après une légère niodificalion des significations, ce développement d'une Fonction hj'pergéométrique générale : S = Il • F{a+s,ß-ts,a + 2s+l,y) ■ F{d-, s,—s,y,x), (1) où la série ainsi obtenue est convergente dans le domaine t£" (!,{/), et où il faut admettre \y\ < 1; de plus, il faut supposer que ni ; ni S ne sont égaux à un négatif entier. Posons particulièrement dans d) x = 1, ce qui est permis, puis remplaçons y par x; la formule de Gauss ^^"' ^' ^^ ^^ = ~r(r-a) r(r~ß) ^^ donnera: tuj,p,,,x) - r(d-r+ 1) "^ s\ /'(r + s) r(d + 2s) • X'- F(a + s,ß + s,a-r2s+l,x), [à) formule qui est valable, pourvu que a'| < 1; on voit ([ue l'hypothèse (î= y donnera, en vertu de (3l, cette formule plus élégante: n«) r(ß) _ _ 'y^rça + s; nß + s) y,^ ^ s ä \ s r 2s+l v) i4) Cela posé, cherchons ensuite dans les deux membres de di les coefficients de la puissance .i", puis mettons x et ;- au lieu de y et o, il résulte ce développement : „ _ 'V^ (- l)^r(« + n + s)/'0? + n + s)/'(r+2n + s) ^ s! r(r-L2n + 2s1 Tfa + n) r(/9 + n) X Il + s , (5) r(r + 2n + 2s) r(a-^n) nß + n) • F(a + n -\- s, ß + n -\- s, y -h 2n + 2s + 1, X) , valable, pourvu que x, < 1. Considérons maintenant la série de puissances fix) = Oo -^ QiX -l- UoX'' + . . . + OnX" + . . ., (6) dont le rayon de convergence est égal à r, puis développons, en vertu de (5), toutes les puissances qui figurent au second membre de (6i , nous aurons une série à double entrée J, dont les séries horizontales sont les développements susdits, ordonnés 14 (le sorte que tous les lennes qui contienueul la même fouclion hypergéométrique forment les séries verticales de J; il est évident que les séries verticales de J se présentent sous cette forme: {-!)" l'(a-\-n)r{ß + n) lin = .r" • F(a^n,ß'[-n,r^-2n-rl,x) S = n I {n-s)\ r(a + s)riß + s)' '• (7) Supposons maintenant |.x| < 1 et jxl < r, les séries horizontales et les séries verticales de J seront convergentes comme des séries de puissances, de sorte qu'il est permis de sommer d'abord les séries verticales, ce qui donnera le théorème suivant: IV. La série de puissances (6) est déueloppuble en série de fonctions hypergéomé- triques comme suit: f(x) ^-= y^ ^-IfAsX^- Fi« + s,^ + s,i-4-2s i-l,x), s = I) OÙ nous avons posé pour abréger: (8) _ r(«+n) l\ß + n) V (-1)^ Fir + n + s) ^"~ nr + 2n) '^^ (n-s)! /'(« + s) /'(/? + s) ■ "*■' ^''' tandis qu'il faut supposer que y n'est pas égal à zéro ni à un négatif entier. La série (8) est convergente pourvu que nous ayons à la fois x < 1, x < r. Ce théorème général, (|ui est certainement nouveau, présente un intérêt parti- culier, parce que la série (8) est applicable à des fonctions qui ont un point ordi- naire dans le point x ^ -f 1 , lequel est singulier pour les fonctions hypergéomé- triques. Remarquons encore que la série (8) est à considérer comme une généralisation très étendue des séries neumanniennes de première espèce selon des fonctions cylin- driques. En effet, prenons pour point de départ la formule de P. -A. Hansen'): (2) ^- ■''^^■'-> = /V+1) • '■'" ^ (^'^'' ^ + 1' -i'ä'). (10) où il faut faire croître au delà de toute limite les deux paramètres k et A', puis mettons dans (8) et (9) {— l)sa.>s{kk'Y au lieu de Us el — x'^ : (kk') au lieu de .i', nous aurons formellement ce développement: ^ -^i^^-(x) -^M^-^-W, (11) s = Il s = 0 ') Handbuch der Theorie der Zylinderfunktioneii, p. 10; 1904. 15 où nous avons posé pour abréger : s = Il c'est-à-dire précisément la série neumannienne de première espèce'). Du reste, il est facile de rendre rigoureuse cette démonstration de l'existence des séries neiimaimiennes; cependant une telle démonstration rigoureuse ne présente aucun intérêt particulier, parce ipie nous connaissons déjà à Fond les séries en question. S 6. Autres propriétés des séries de fonctions sphériques. Dans mes Recherches sur les fonctions sphériques') j'ai déduit (juelques pro- |)riétés communes des coefficients de la série neumannienne f{ax) --= r(v) ■ ^ (v f s) A'- '{») P" Hx); (1) s = Il en terminant ces recherches sur la transformation de la série (1 ) il me semble utile de développer d'autres propriétés des coefficients susdits en démontrant ce théorème : V. Les coefficients A" "(«) '/«(' fujnrent au second membre de (1) satisfont à ces deux équations fonctionnelles : (y -r- n + 1) A'' + '■ "(«) = A" "(«) — A' " + "■'(«) (2) «0«^"+ ' "(«) = nA" "(«) + (n + 2v — 2) A'- " + -'(«), (3) et cela quelle que soit la fonction f(x). Pour démontrer la formule (2) prenons pour point de départ l'identité-') (s + vjP'-'Hx) == vCP^ + i -"(.r) - P'+''--U-)) nous aurons, en vertu de (1): f(ax) = /'(i> + l) • y^ (A'' Ha) - A"- ■' + "■'(«)) • P'+'Ux); s = Il car nous aurons toujours pour n positif entier') P''-"{x) = 0. Posons ensuite dans (1) i> -p 1 au lieu de u, puis remarquons qu'une fonction ne peut être développée que d'une seule façon dans une série neumannienne pour ') Handbuch der Zylindert'uiiktioiien. p. 27'i. -) loc. cit. p. 53 (291). ■'I loc. cit. p. 15 (25.S). '} loc. cit. pp. 34 (272), 14 (2.')2). 16 laquelle le paramètre v a une valeur déterminée: nous trouvons immédiatement la formule (2). En second lieu appliquons l'identité ') 2(v + n).rP'' "(.r) = (n + 1) P"- " + '(.r) + (n + 2u — 1) P^ " '(.v); nous aurons, en vertu de (1) : s = X lxf(ax) = r(u) • y^ (s/i"'^-' (a) + is + 2 i/)A^' "■ + '(«)) • P' "(x). (4) où nous avons à poser A" '(«) == 0. Cela posé, dilférentions par rapport à x la formule (1), puis apjiliquons les identités ') IKP' "(x) = '2> ■ P"+' "- '(:r), P'"(x) = 1, nous aurons: af'"(ax) -= 2l\y-Y\) • ^ (s + v + 1) A'-"+ ' (a > • P^ + ' »(X); (5) s = Il posons ensuite dans (1) !^ + 1 au lieu de >, une differentiation par rapi)ort à « donnera : xf^'^Hax) = r(!/ 4- 1) . y^ (s + V + 1) DaA' + ^ '(o) . P''+ I- ''(a-), S = Il d'où en multipliant par .v la formule (5), puis appliquant la transformation {4), nous aurons immédiatement la formule (3). Reniar(juons en passant que les formules (2) et (3) sont des généralisations des équations fonctionnelles que j'ai prises comme définitions des fonctions cylin(lri(iiies''). En effet, mettons: A^^ia) = /"(^J'C + 'H«), nous aurons, en vertu de (2) et (3), si nous posons encore n — 1 au lieu de n: 2(v^r_n_) , c' + 'Ha) = C' + ^-Ha) + C' + " + '(a) 2DaC' + ''(a) = C'' + «-i(«)— C' + n + 'M; c'est-à-dire que la fonction C'' + "(«) coïncide avec la fonction cylindrique de pre- mière espèce J" + "(«). ') Recherches sur les fonctions sphériques, pp. 34 (2721, 14 (252). -) Handbuch der Zylinderfnnktionen, p. 1. 17 CHAPITRE II. Applications aux fonctions cylindriques. § 7. Sur la fonction de Lommel. Il esl intéressant, ce me semble, que notre première généralisation de l'identité d'ABKi. est également applicable à une série de fonctions cylindriques. Pour effec- tuer la transformation correspondante, nous avons à prendre pour point de départ la formule intégrale S i J" (g- cos y) (sin ^p)-'' ' ^^ _ r{b) t2V> ^a - b. a -f- b ,^. (^. (cos^)"-' ' 2cosb;r \a7 où //" "(.r) désigne la fonction de Lommel, savoir: n'pu) = cos^ (v -p) • y -7-^ ^ ,, (2) tandis qu'il faut admettre M(b) > 0. La formule (1) peut être démontrée si nous introduisons la série ordinaire qui représente la fonction cylindrique J^ix), et si nous appli(|uons ensuite l'intégrale eulérienne de première espèce S 1, (•^)- Il saute aux yeux ([ue la fonction de Lommel est une généralisation de la fonction cylindri(pie de première espèce; nous aurons en effet: //""(.v) = ./"(.r,, //"-"(.cl = cosa,-r • ./"U); (3) dans ce qui suit nous avons à faire usage de ces autres cas particuliers de la fonc- tion de Lommel: /7^(xj = /7^."(a.-j = cos ^' • > - ~ ^— (4) /'=v+'cos|(.-^i t^, rj-s + llrls + v + i) (6) Appliquons ensuite la méthode ordinaire, nous obtenons cette autre formule intégrale analogue à (1): l>. K. I) Viilfiisk.ScIsk.Skr.. 7. Hukke, niiluiviiiensk. ii« niiilhcni. Al.l V. 1. 3 18 } (^^f~' " 2 sin/,;. \.v) ' " ^'^^' ' • où il faut admettre aussi ^H (b) > 0. Cela posé, il est évident que la formule (1) nous permet de déduire directe- ment une suite d'intégrales défmies qui contiennent la fonction de Lommel, en Iransformant simplement des intégrales correspondantes contenant une fonction cylindrique. Or, de telles intégrales étant restées inaperçues jusqu'à présent, il nous semble utile de les développer ici dans leur ensemble. 1". La formule élémentaire ') ! J'{xco%f){co'>fy + Us,\n(pfP 'df = ^-rP^^ ■ -l' + fU-), xP où il faut admettre ''M(p) > 0 et iHiv) > - 1, donnera immédiatement, après une légère modification des significations, la formule correspondante s: /7''''''(xcos^)(cos^)'-'+'(sin^r^'' hl

0, 'i)i (p -\- i') > —2; du reste, il est très facile de déduire directement la formule (8). 2^. I^'intéorale fondamentale de M. H. Weber ^) ■ritxji^U = :^r-r :v-:4^, O) 2^ ^f-^) où il faut admettre x positif réel, ^K(i/+/>) > ~ 1 et 3Î (/>) < -^ , donnera comme formule correspondante celle-ci : i 5 - \ 2 / --- 2 - /2\''+' 2 ■ p/l + v-ffi „Il +y + p\ n^Pitxwdt = ^ . ^^,._„, ,;^:^„: ,, ' ^ — = (-) , dO) ^r-n"')/^r-^2^-v(i-^) -!(,+.) où il faut admettre .T positif réel, ''M{p — v)>(\, ^W (/> + (t) > — 1 et 1 > 3î(2 // ^ 0, tandis que n et p sont des entiers non négatifs et >K(:> r n) > — 1, Ï'K((T — v) > 2n~\-'2p4~ 1, nous aurons immédiatement la formule correspondante ~ ^^ ^ ^ ■ J''(tx)t' + '-" + >dl = Ü, (13) où il faut admettre a- > y > 0 , 9{ (i/ -]- ;i) > — 1 , 'SUp + a - '2v) > -in f ip + 2, 9î(/>) > 'M (a). 5°. En second lieu, la formule analogue^) C J''(y^^*±^ .Y'{tx)r + ''''dt = 0, (14) Jo (/^ + z2)2-'' où il faut admettre x > y > 0, 9î(w + n) > — 1, :')i((t — i^) > 2n + 2p— 1, tandis que 71 et p sont des entiers non négatifs, donnera : f rL'A^n^pl) . y^(te)p.-rf/ = 0, (15) X (/»+Z^)'-!^'' formule qui est valable pourvu que .i- > ;/ > 0, ^){(i/ + n) > — 1, '^{p -{- a — 1v) > 4n_j_4^, _2, ^}i{{p — a) > 0. (î°. Prenons maintenant pour point de départ la formule') J''{yMf^-\-z^') J''(/.r)r-' + -" + £_p r-~i-u« 1 ') Handbuch der Zyliuderfunktioiieii, p. 252. -) p. 252. ") p. 257. (16) 20 (|iii t'sl viilahlf pourvu fjiiu .v > ;/ > O, ^K (v j n) > — 1, Si (<7 — u) > 2 yi -f- 2p — 2, tandis (|iie ;i el p sont des entiers non négatifs, nous aurons la formule corres- pondante : dt = (_l)"J.^^iî/l/^^J^.HÏ(xa/)a--.;^ "Vr.i {Z^-U^Y " (17) où il faut admettre x > y > 0, lH (v -f n) > — 1, Si (/> + ff — 2v) > 4/1 + -ip — -. La fonction H qui figure dans les deux dernières formules est la fonction de Hankel, savoir: //ï(x) = JMxi + jyCa;). Cela posé, meltons dans (17) z = u, ce qui est [)crmis, l'intégrale ainsi obtenue aura pour p > 0 la valeur zéro; dans le cas particulier p = 0 nous aurons au contraire: \ (P-^z^)^^' .f'{i.v)t' + ^" + ^dt (18) ;ry'^.-^ + 2'.cos (T-/,) ^^ „,. = (-1)" -~ ^- , • HU.vzi]e 2 . Posons encore dans (17) u = () , la valeur de l'intégrale ainsi obtenue sera égale à zéro, pourvu que ;î > 0 et 9i (v) > — n; dans le cas particulier n ^ U nous aurons au contraire: 7°. Eludions en dernier lieu la formule analogue à (16)'): (19) » " J'^(yl/f' + r'=) y(fx-)P+^" \ "-p ' f' + u' dt (._!)" -^.:^yJ^^^ .HÏ,..On---'.;^^ (20) où il faut admettre .r > ;/ > 0, J)i (i/ + a) > — ' , 9Î (^r — w) > 2;» + 2/> — 1, tandis que ;i et p doivent être des entiers non négatifs; nous aurons: ') Handbuch der Zylinderfunktioiieu, p. 257. 21 1 (t^ + zn^ " TCl -i - - . ^ - P (21) où il faul admeltre .v > t/, ïK (i/ + ") > — T' '^^ (/* + 4/) + 4/) - 1, Posons ensuite dans (21) n = r, l'intégrale ainsi olMenue aura pour /) , O la valeur zéro ; pour ja = 0 nous aurons au contraire : 2''+'r(^±^ + i)r(^^ + i) •' (221 § 8. Séries de fonctions de Lonnmel. Prenons maintenant pour point de départ la formule intégrale § 7, (1); il est très facile de démontrer ce théorème général : VI. Supposons que la série de fonctions cylindriques f{ax) = {^ly-^ As(a)rUh.v) (1) s = Il satisfasse aux conditions énumérées dans /e § 2, nous aurons ce développement en série de fonctions de Lommel: n^ ' ^^ Ps 772" \xj .^L^ oil nous avons posé pour abréger %Aa^ = a^-"- . nß''"^^'^f^d,, (3) tandis (pi' il faul supposer 0 < ;K ( — 1. On connaît depuis longtemps des cas particuliers de (2)^); néanmoins la formule générale (2) est nouvelle. Appliquons maintenant l'intégrale de Bessel*) 2 . {■'-)" f«-J ■f '" (-^-J = _ , ^ ,, • \ ■ cos (a- sin ^) (cos ipfd,/^, (3) ') Handbucli der Zvlinilerfunktioneii, p. 20. -) p. 63. ■') p. 51. 24 oil il faut admettre >H(i/) > — 9 ' """^ aurons, en vertu de (2), pour le produit de deux fonctions cylindriques cette intégrale double. ,f^~{x)J^-^(x) = -~^ "A ■,, • \ \'' cos(2.vsinçAcos^)(cos£^)''(cost«)*^c,os(«t^))rff rfç's (4) où il faut admettre 9Î (1/) > — t, . Remarquons encore en passant que l:i formule S 1, (13 bis) donnera cette inversion de la formule intégrale (2j: .ru-) = \d, ^^ j^^piin_2^) r/^^^1') (.vsin2^)(col^Ard^, (■'■>) où il faut admettre 3Î (1/ — p) > — 2. Il saute aux yeux que la formule intégrale (2) est applicable à la plupart des intégrales que nous avons transformées dans le § 7. 1°. L'intégrale de M. Weber § 7, (9) donnera après une légère modification des significations cette autre formule: r.^ 2-0,- ''- 1 W'+^+^+f) r{- o) où il faut admettre .v > 0, 'iH {v -]- p + a) —1 et $K (<7) < 0; la formule (li) est très connue'); mais notre démonstration est nouvelle. Remarquons en passant que ce développement de la formule (6) nous donnera une nouvelle démonstration de la formule de Gauss concernant la valeur de F (a, j3, y, 1). 2. Les intégrales §7,(12) et (14) donnent de même immédiatement ces deux autres C /^(y^lJ^^yß) . . p . .„ . , rf , =. o . (7) \ -'^''iy^ôJjJyS . Y^tx) . r+^-dt = 0, (8) nil nous avons posé pour abréger: i? = VWTl^, (9) tandis qu'il faut ajouter aux conditions précédentes ces deux autres: .r > 2 y et afî(<7) > — 1. ') Handbuch der ZyliiiderfunUtiimen, p. 194. 25^ • 3°. Posons encore pour abréger: o, = Vz'- — u^; (10) les deux formules § 7, (16) et (20) donnent ici ces formules analogues: j: 0; le cas particulier p ^ 0 donnera au contraire: X 0 et 5R(i/) > — n; dans le cas particulier ;» = 0 nous aurons: r. a+T a [■LUyRllAy^. . ,r^tx)r un = ""^^^ • J^iyz)J^iy.^. (14) J ß" x^z" § 10. Séries de produits de deux fonctions cylindriques. Comme une application beaucoup plus importante encore de la formule inté- grale § 9, (2) nous avons à démontrer le théorème: VII. Supposons que la série de fonctions cylindriques x"f(ax) = ^ As{a)J''HPsX) (1) s = 1 I). K. n. Viclensk. Selsk. Skr., 7. llickke. niiliiiviiliMisU. ciB m;ilhcni. Alil. V. 1. « 3l„(a) = DA' An{asm2(/>)iasin2il:)'' + '(col arc sin /c^ r) (1 — z^)' ^ ^ ^ _ > A-S-' • \ i' + l "*' (6) où .r désigne une quantité réelle, telle que ;r(/>-y 1. L'accent fixé au signe 2' qui figure au second membre indique qu'il faut prendre la moitié du terme qui correspond à s = p, dans le cas particulier où l'égalité a lieu dans la limite inférieure de (7). Dans le cas particulier où ^ ^ < x' < + y , la somme de la série infinie (jui figure au premier membre de (6) est égale à zéro. Posons particulièrement dans (6) v = 0, ,o = 1 , nous retrouvons la formule élémentaire très connue: ') Handbuch der Zylindeifunktioiien, p. 340. 28 (-l/-'sin(2sx) X y^\ tandis que l'hypothèse v = /> ^ 0 conduira à une autre formule particulière que j'ai développée dans mon Traité^) sus-indiqué. Nous aurons dans ce cas la formule s -p ^(-l)».,(./"a-.r))'= -^, -^VI^aJ, (9) s = I où F(~ , k\ désigne l'intégrale ellipti([ue complète de première espèce, tandis que l'hypothèse v == /> = \ donnera la formule analogue ^^ SX - , . , t: . \x s = 0 ^^^- • •^"(-)-^'(-) ^ — 'i^ • X'^^'^ ^^Iv^^J' (10) où E (y , l<] désigne l'intégrale elliptique complète de seconde espèce. Remarquons en passant cpi'il est très facile de démontrer ces théorèmes con- cernant des cas particuliers de la série (6): 1°. Supposons que v et /> soient des entiers non négatifs de la même parité, la somme de la série (6) s'exprime sous forme finie à l'aide des intégrales elliptiques complètes. 2°. Dans le cas, où m et ij sont des entiers non négatifs de parité différente, la somme de la série (6) est un polynôme entier de rr. 3°. Supposons que v et f) soient des nombres rationnels parmi lesquels un au moins est fractionnaire , la somme de la série (6) s'exprime sous forme fmie à l'aide des intégrales hyper elliptiques. Remarquons en passant que l'intégrale S 8, (!)) peut également être transformée à l'aide de la formule ,^ 1, (10), mais (ju'une telle transformation ne présente qu'un intérêt médiocre. CHAPITRE III. Sur une équation différentielle linéaire. § 11. Équation du quatrième ordre obtenue pour C^(x) ■ C^'{x). Il est évident que la méthode que j'ai appliquée dans mon Traité des fonctions cylindriques en m'appuyant sur un cas particulier de la formule intégrale s^ 9, (2) est également applicable à la formule générale. De plus, il est évident que cette méthode généralisée nous donnera sur-le-champ les équations différentielles que j'ai M Handbuch der Zylinderfunktionen, p. 347. 29 ol)tenues pour les produits de deux lonclions c-ylindri(iues en suivant une méthode un peu plus longue. Pour obtenir l'équation différentielle à laquelle le produit de deux fonctions cylindriques quelconques doit satisfaire nous avons à prendre pour point de départ l'équation ditTérentielle de Bessel 2«) _L r(ll ('"-.^) = 0, z --= ./«(«.r), ce qui donnera en vertu de la formule intégrale Î5 S), (2) pour la fonction a + b a — b cette équation non homogène : y'"+.r î'"'-|^-''= ^'' oil nous avons posé pour abréger: 2 V "' F U = -y -'"(2 xcoii(p) {2 cos w)" cou {b(p)d{x) — {2h — 2) W-^''(x) Ci) Cela posé, remarquons que la définition (2) donnera immédiatement ces deux identités: ("X^> 30 V-^'i.v) = ^. • (2) •■/ - W-/ ^ W (4) \l' + -2 puis multiplions par (M " les deux membres de (3), une dittërentiation par rap- port à X donnera celte autre équation différentielle : ni , 3 + fo ,2, , /. , 1 + ft — a'\ Mw /4-f 46 a^bv ; • b{l>~l) U"'-''(x). (B) Multiplions ensuite par I *, j les deux membres de (6) ; une nouvelle diffe- rentiation par rapport à x donnera finalement, si nous posons encore 9 a — b l'équation ditl'érentielle cherchée: „..,+1 „».+ (4 + l^'^fl) „..+ (!^ + L^^^^i^) y"+ + (.|. + *^i.^'^> = » (7) qui admet certainement comme intégrale particulière la fonction y == ./"(.r) ./-"(a). Remarquons maintenant que les signes des deux paramètres y et ^ peuvent être choisis arbitrairement; il est évident que l'équation différentielle (7) a comme intégrale complète la fonction y = c, J''{x)JP(x)-±c^ .rix) y'^(a-) + C3 Y''(x)JP{x)^c, r-'(x) Y''>(x), (8) où les Cg désignent des constantes arbitraires, fonctions de v et p. § 12. Équations différentielles du troisième ordre. Revenons maintenant à l'équation différentielle § 11, (6); il est clair que les deux cas particuliers fc ^ 0, b = 1 présentent un intérêt particulier, par ce que ces deux valeurs de b font disparaître le second membre de l'équation susdite. 1°. 5 = 0; posons a = 21/, il en résulte cette équation: y.:^) + ,«) . qui admet comme intégrale complète la fonction y = c, {J''(x)y + c, ./"(.lOi'^GiO-f c, (rM,r))'. (1) (2) 31 En effet, introduisons dans (1) la série y =^ a,-x'< + -'\ (3) s = l> puis appliquons la formule eiilérienne concernant la fonction r(2w); nous aurons, en vertu de S 9, (D, ces trois intégrales particulières: (J^f.r))^ (./-''(.r))\ J^(.r)./-''(.v), ce qui nous conduira immédiatement à l'intégrale complète (2). 2°. b = 1; nous aurons ici l'équation différentielle analogue à (1): „.+±,,«,+(4+^«'),..+(l-î-:)„ = o, équation qui admet certainement comme intégrale particulière la fonction (4) g+l g— 1 y, = ./ "^ (X) J 2 (X). (5) Pour déterminer maintenant deux autres intégrales particulières de (4), intro- duisons-y la série (3); nous aurons la formule recursive (A-+2S+ l)(Â-+2s+a)(A- + 2s- a) a, + 4(A- + 2s) a^-, = 0, et pour k les valeurs suivantes: k =^ a, A^^— a, k = — 1. L'hypothèse k = a nous conduira à l'intégrale (5), tandis que Ar = — a don- nera cette autre intégrale particulière: 1— g g+l y 2 = ./ - (X) .1 -' (X). (6) L'intégrale qui correspond à A =^ — 1 se détermine sous la forme suivante: ^ ris ce qui nous conduira à considérer ce cas particulier de § 9, (1): appliquons ensuite l'identité évidente 32 nous aurons en vertu de la formule eulérienne § 1,(5) pour y.j cette autre expression: g-l _ u + 1 COS -^ j,, = ./ ^ (x)./ -^ (.r) — '• (7) Combinons maintenant les deux intégrales y, et y^; la définition de la fonction cylindrique de seconde espèce Y^(x) donnera cette autre intégrale particulière de (4): g — 1 11 + 1 , y, = ./ '^ (X-) y "-i (-v) + ^^.- (S) Quant à l'intégrale (6), appliquons l'identité J- "(x) = cosi;;r ./"(.rj — sin y?: y'(.v), et la formule fondamentale de Lommel: V' - ' (.r) .r\x) - y ^ (.r) J^ - ' (.i') = — ; nx nous aurons cette autre intégrale particulière de (4): g — 1 o+J. !/, = y ^^ (x) y ^^ (:r), (9) de sorte que nous avons démontré ce théorème qui est certainement nouveau : VIII. Supposons différent de zéro le paramètre a, l'intégrale complète de l'équa- tion (4j se présente sous la forme g— 1 g + 1 g — 1 g + 1 , g — 1 a + l ■. . y = c, J^(x)j'^(x) + c, Y '- (x)Y ^ (x) + c, l.T 2 (.r) y -^ (x) + -~_y (10) Dans le cas particulier a ^ 0 nous aurons: .Ax).r^(x) = - y^(.r) y"^(.r) = ^"^^ pour obtenir dans ce cas une troisième intégrale particulière de (4) nous pouvons prendre la fonction a+l g~l 1 — a 1 4-g J~^(x) J~^{x) - J^jx) J 3 (.V) ^ sin ar: ce qui donnera, pour a == 0, l'intégrale cherchée sous la forme (11) 33 § 13. Représentations intégrales de ^"(æ-) • C + Uæ). Dans mon Traité des fonctions cylindriques j'ai étudié d'un point de vue général une classe d'intégrales définies parmi lesquelles la suivante: x-^xBixy) =\ C''{tx)tP(t^-iry^fdt, w=^J-2ff+l (1) est une des plus simples; la fonction S (x) qui figure au premier membre de (1) satisfait à cette équation différentielle du troisième ordre: @(3)(^.) 4_ 3 -_2i" . @(.)(.^) + ( (i-Ll-il' -Jl! _ 1 ) @(.)(a:) + ^ • @ (x-) = 0 . (2) Posons ensuite dans l'équation différentielle § 12, (4)|: et dans l'équation ainsi obtenue px au lieu de x, nous aurons l'équation différentielle -''' + ^ -"''*+ (^^' + (« — 1)(3«-2) — g' x-^ ) z(^' + 4p^(2-aj (a — l)(tt-a)(« + a)\ , _ \ a; X qui admet comme intégrale complète la fonction ')- = ». (3) / a+ 1 g— 1 g+l a— I : = a;«(c, J "^ (/jx) J^~(/)x-) + c„ Y '^ (jax) Y ^ (px) + (4) Cela posé, il est évident que les équations différentielles (2) et (3) deviennent identiques sous les conditions suivantes: p = ~, 4 — 3a = 3 — 2«>, « — 2 = 2ff (« — l)(3a — 2) — a^ = (û,_ 1)2 — ^2 («-l)(a-a)(a + a) --= 0, de sorte que nous avons à étudier séparément ces trois cas différents: 1. a = ^ = w = l, — 2, et qu'elle représente dans ce cas une fonction analytique de v. Multiplions ensuite par .v" les deux membres de (1), puis faisons converger à zéro la variable positive x; l'intégrale ainsi obtenue aura un sens pourvu que — 2 < 9{(i>) < — 1, ce qui donnera pour y = 1 : -^ • \ -== dt fl) ] Vt^ + 1 d'où en appliquant des formules très connues concernant la fonction gamma: Ttf 2 COS -2 Pour déterminer le coefficient Cg mettons dans (1) y = 0; l'intégrale ainsi obtenue a un sens, pourvu que 9î (y) > — 1; nous aurons, en vertu de l'intégrale fondamentale de M. Weber § 7, (9): ni c, ^ 2 cos y Quant au coefficient c.2, il est facile de voir qu'il doit disparaître; en effet, supposons 'ia (v) > 0 , puis mettons dans (1) x --= 0 , le premier membre de cette formule s'évanouira, ce qui n'est possible pour le second membre que si c^ = 0. Cela posé, nous aurons finalement la formule: qui est certainement nouvelle; dans (2) //./(.v) désigne la fonction de Hankel, savoir //,«(.r) = J''(x) — iY<'(x). (3) 35^ Changeons ensuite dans (2) le signe de v, nous pouvons déterminer sans peine la valeur de l'intégrale correspondante qui contient une fonction cylindrique quel- conque. Nous ne nous arrêterons pas à une recherche plus approfondie d'une telle généralisation de (2); au contraire nous préférons soumettre notre formule (2) à une légère transformation. A cet effet, mettons dans (2) — iy au lieu de y, puis supposons pour un instant réels la nouvelle variable y et le paramètre y; il résulte, en égalant les parties réelles et imaginaires de la formule ainsi obtenues, ces deux autres formules: dont la première est certainement nouvelle, tandis (|ue la seconde coïncide avec un cas particulier de notre formule générale g 9, (2). §15. Etude de l'intégrale ^ ,/^ + i(<.^)«'' + ' • («' + //") -dt. Dans le second cas du § 13 nous obtenons tout d'abord une formule de la forme J-^ + ^(tx)r + *.^ y ■2'-+l 1 ■ — u c..^(^)^>-(^) äi^^—.c,jn-^-j>+n^' + ^0 it' + y'V d'où, en suivant la méthode ordinaire, cette détermination des coefficients c«: C3 = 0 (1) ; — al- — 1 c, = sin vn c„ = 2''-^V7z r(:/ + y)z2'' + i- sm vt: ce qui donnera la formule cherchée (2) 1 3 qui est valable, pourvu que x soit positif et ^ > 9i (v) > — ^i quant à y, cette variable ne doit être purement imaginaire que si nous supposons encore 5R(v) > — y. Cela posé, mettons dans (2) 2.v au lieu de .r et — iy au lieu de y, nous aurons une identité de la forme: = ^ ^ (./^(.vy)J''+i(xy)cosi/ff — X " sin vTT \ — /./"(a- y) ./^ + ' (.ry) sin s.;: + J" "(.vy) ./-"-' (æy)) , ce qui nous permet de déterminer la valeur du facteur (— 1) - qui figure au premier membre; nous aurons par là, après une légère modification des signi- fications : C^ 2''-»r(v+|)K;r \ J' + '{'2xcosw)(cos — o ' ^^ formule (3), qui est certainement nouvelle, peut aussi se démontrer sans peine par un calcul direct. De plus, nous aurons cette autre formule : J^ + H2fx-)P + ' , „ 2-"^^.4 + l)y- + ' dt = (4) ■ (^J'{xy)J'+'(xy) cosi;;: + J-''(.ry)J-^-'(-vy,)), où il faut admettre g > 3i (uj > — y^ posons dans (4) u = 0, nous aurons, après un simple calcul, un cas particulier de la formule § 14, (4). Table des Matières. CHAPITRE I. Applications aux fonctions sphériques. Page § 1. Généralisations de l'identité d'Abel 5 § 2. Transformation d'une série de fonctions P^' " (.r) 7 § 3. Application aux séries de C. Neumann 9 § 4. Séries de fonctions F W -'- n, — n, f> — \, x) 11 § 5. Séries de fonctions hj'pergéométriques générales 13 § 6. Autres propriétés des séries de fonctions sphériques 15 CHAPITRK 11. Applications aux fonctions cylindriques. § 7. Sur la fonction de Lommel 17 § 8. Séries de fonctions de Lommel 21 § 9. Sur le produit de deux fonctions cylindriques . 23 § 10. Séries de produits de deux fonctions cylindriques 25 CHAPITRE 111. Sur une équation différentielle linéaire. § 11. Equation du quatrième ordre obtenue pour C (x)- C' (x) 28 § 12. Equations différentielles du troisième ordre 30 § 1 3. Représentations intégrales de C^ (.r) ■ C " + ' (.r) 33 § 14. Etude de l'intégrale 'C C'Ut x) i (f ^ ir)~ ^ d i 34 §15. Etude de 1 intégrale r 7" + ' (/.r) ("■+'•('■' — !/■')" ^^'" 35 DANSKE ARTER AF SLÆGTEN CERAMIUM (ROTH) LYNGBYE AF HENNING EILER PETERSEN D. Kgl. Danske Vidensk. Selsk. Skrii'tkk, 7. Række, naturvidensk. og mathem. Apd. V. 2 KØBENHAVN BIANCO LUNOS BOGTKYKKERI 1908 A. Indledning. Quamquam Species Ceramiorum ante alias Algas fere onines ad oras Europæ fréquentes obveniant, tarnen confiteri fas est vix existere Floridearum genus cujus Species rêvera minus in- telliguntur. (J. G. Agardh : De typis Ceram, pag. 3.) Tlie Ceramia are almost as unsatisfactorj' to the Botanist as the Rubi, and their varieties quite are numerous. (Harvey: Phycol. brit.) De 'en første af de to Udtalelser, som jeg har stillet foran denne Bearbejdelse af de danske Cerainium-Arter, siger os, at Ceramiuni-Slægten i Modsætning til, hvad man kunde vente, naar man tog Hensyn til, at dens Arter forekomme overmaade hyppigt, ikke i nogen særlig Grad har nydt Botanikernes Gunst. Den anden Udtalelse giver os Forklaringen paa dette Fænomen: Ceramium-Slægten er indenfor Algernes Omraade, hvad Rubus o. a. Slægter er blandt Blomsterplanterne, et Om- raade, hvor den menneskelige Aand vanskeligt finder sig til Rette i sin Trang til at forme bestemte Kategorier, Arter, kortsagt et Omraade, som endnu befinder sig i Udvikling. Nøjere bestemt kunne vi karakterisere Ceramium-Slægten som et Om- raade, i hvilket der kun findes faa skarpt adskilte Arter, derimod en stor Mængde Former, som gruppere sig om bestemte Typer og som i højere eller mindre Grad flyde over i hverandre. Denne sidste Egenskab gør enhver systematisk Behandling overmaade vanskelig og paa de fleste Punkter lidet tilfredsstillende. I flere Tilfælde maa Systematikeren egentlig give tabt og kun Trangen til de bestemte Kategorier faar ham til at træffe sine Afgørelser, hvad dog nærmest kun vil sige med Navne at bringe Orden i Virvaret. Man føler bedst her, hvor lidet den systematiske Methode strækker til, naar man staar overfor Omraader, der er i stærk Udvikling; her burde man, som det er bleven gjort gældende, kun tale om Udviklingsrækker eller lignende. Den eneste sikre Løsning af de Problemer, som Ceramium-Slægtens Arter og Former stiller os, vil kun naaes ad Experimentets Vej. Men i saa Hen- seende er der vistnok endnu langt tilbage. Den foregaaende Karakteristik af Ceramium-Slægten og de dertil knyttede Betragtninger vil tydeliggøre, hvormegen objectiv Værdi man bør tilkjende de her 6- 42 4 i dette Arbejde beskrevne Arter og Former, som ikke er skarpt begrænsede fra Naturens Haand. Jeg betoner dette saameget desto mere, som jeg paa flere Punkter divergerer fra en Forsker, der for ganske nylig har givet Bidrag til Kundskaben om denne Slægt, H. Kylin. Til Grund for nærværende Bearbejdelse af de danske Arter af Slægten Ceraniium ligger i Hovedsagen Materiale (væsentligst Herbarexemplarer) samlet af Hr. Docent Dr. L. KoLDERUP Rosenvinge gennem en lang Aarrække. I Forhold til dette Mate- riale, der omfatter over 300 Numre fra c. 150 Lokaliteter og som giver et meget fuldstséndigt Billede af Ceramium-Slægtens Forekomst i vore Farvande, træder de Oplysninger, som Forfatteren selv har kunnet skaffe tilveje og som det botaniske Museum har kunnet yde gennem sit Herbarium, fuldstændig i Skygge. Fra først af, da Dr. Kolderup Rosenvinge overdrog mig at bearbejde denne Slægt, var det Meningen, at min Behandling skulde fremtræde som et Led af det Arbejde over de danske Havalger, som denne Forsker for Tiden har under Udarbejdelse. Af for- skellige Hensyn fremtræder mit Arbejde allerede nu og som noget selvstændigt. For den Tillid, Dr. Kolderup Rosenvinge viste mig ved at overdrage mig Behand- lingen af denne Slægt, der frembyder saa store Vanskeligheder, ligesaa for den Elsk- værdighed, hvormed han altid har støttet mig i dette Arbejde, bringer jeg ham her min hjærteligste Tak. Slægten er behandlet næsten udelukkende fra et morphologisk-systematisk Syns- punkt. Hvad der ved første Gennemgang viste sig som det, der skulde udføres: nemlig en grundig Redegørelse for de mange Former, der fandtes i Dr. Kolderup Rosenvinges Materiale, har beskæftiget mig i den Grad, at andre Spørgsmaal af mere almindelig Interesse f. Eks. Befrugtningsforholdene ikke er blevne paaagtede. Af de 9' Arter, som omtales i dette Arbejde, er de 7 beskrevne tidligere og i det Hele taget Arter, der er almindelige og som derfor atter og atter er bleven omtalte af Systematikerne. Ikke destomindre hersker der den største Uklarhed over disse Arters Begrænsning, en Uklarhed, som jeg efter bedste Evne har søgt at raade Bod paa. Jeg har dog i mindre Grad søgt at udfinde, hvad Autorerne have ment; meget mere er jeg traadt i Skranken for personlige Opfattelser og helt uden Betyd- ning er vel saadanne ikke, naar de iøvrigt støttes ved nøjagtige Undersøgelser af de paagældende Objekter. Det, som det foreløbig kommer an paa ved Ceramium- Slægten er, at man skarpt præciserer de enkelte Former og Arter — har man erkendt Realiteten, er Navnet uvæsentligt. To nye Navne har jeg dannet 1. Cer. vertébrale for en ny Art(?) i Østersøen og tilgrænsende Farvande og 2. Cer. Rosenviiujii for visse Former indenfor et Om- raade, der tidligere lienlaa i stor Uklarhed (C. rubrum a decurrens J. G. Agardh). En Mængde Former har jeg opstillet; maaske for mange. Ved „Form" forstaar ' 10 med den i Efterskriften nævnte Cer. Deslongchanipii. 5 43 jeg iovrigt kun det, der indenfor Arten fremtræder som noget selvstændigt uden Hensyn til Aarsagerne. Af yderligere systematisk Nyt kan jeg fremhæve, at det er lykkedes mig at finde Midler til at erkende C. teniiissimtim i vegetativ Tilstand. Af mere almindelig Interesse er Paavisningen af Parasporernes Udviklingshistorie og deres Uafhængighed af Tetrasporerne ^ Ved hver enkelt Art ere dens biologiske Forhold som f. Eks. Fruktifikations- organernes Art og Hyppighed, Livsperioden, Lokaliteten, saavidt del lod sig gøre, bleven nævnt og dens geografiske Omraade indenfor vore Farvande, saalangt vi foreløbig kan bestemme det, blevet antydet. Men dette er ogsaa alt. Man vil saa- ledes ikke i dette Arbejde finde noget om vore Algesamfunds Sammensætning og Ceramium-Arternes Stilling deri; ej heller er jeg i nogen nævneværdig Grad kommen ind paa en Fremstilling af vore enkelte Farvandes Saltholdighed og Ceramium- Arternes Forhold hertil — her holder jeg mig kun til de grovere Træk. Disse to Problemer ville senere blive Genstand for en Undersøgelse fra Dr. Kolderup Rosen- vinges Side. Mit Arbejde danner i saa Henseende kun et Led af Grundlaget til denne Forskers Fremstilling. Indenfor den systematiske Litteratur danner J. G. Arardhs forskellige Arbejder, hvoriblandt i Særdeleshed hans senere Afhandling: de typis Ceramiorum diversis og Harveys Phycologia britannica Grundlaget; mindre Betydning har Kötzings Arbejder. Blandt nyere Forskere have bl. a. Foslie, Kjellman og Kylin leveret Bidrag til Slægtens Systematik. Foslies Arbejde over de norske Ceramier er egentlig kun paa Grund af sin Kortfattethed uden særlig Betydning; af de to andre har Kylin ydet det værdifuldeste og det er iøvrigt kun hans Arbejde, som vedrører min Be- handling her. Helt enig med ham er jeg ikke; jeg tror imidlertid at Forskellen mellem hans og mine Opfattelser ikke vil vise sig at være særlig stor. Iøvrigt henviser jeg til den specielle Del. Arbejder, som vedrøre andre Forhold ved Ceramium-Slægten, ville, forsaavidt de overhovedet har Betydning for nærværende Afhandling, blive nævnt i den Over- sigt over denne Slægts almindehge Forhold, som indleder den specielle Omtale af de enkelte Arter. For at undgaa unødvendig Vidtløftighed henviser jeg kun. hvor jeg mener, at der er særlig Grund til det, til de enkelte Lokaliteter og Indsamlingsnumrene. Det, der har Betydning, er ikke saa meget de enkelte Lokaliteter som de enkelte Om- raader. Efter Overenskomst med Dr. Kolderup Rosenvinge benytter jeg følgende Inddelinger og Betegnelser for vore Farvande. Ns. Nordsøen: fra den slesvigske Grænse indtil Hanstholm. Sk. Skagerak: fra Hanstholm til Skagens Gren. Lf. Limfjorden. ' Smlgn. her Kylin (1907); lian har en Bemærkning om, at Para.sporer og Tetrasporangier kunne forekomme i samme Bælte. 44 6 Kn. nordlige Kaltegat. Begrænses mod Syd ved en Linie fra Sæby til Læsø Norvest-Rev og ved en Linie fra Læsø Østpynt mod Øst. Ke. østlige Kattegat. Begrænses mod Vest af KobJiergrunden og en Linie fra dennes Sydspids til Østpynten af Anholt og derfra til Gilbjærg Hoved; begrænses mod Sundet ved en Linie fra Nakkehoved lil Spidsen af Kullen. Km. Mellemste Kaltegat: Begrænses mod Syd ved en Linie fra Anholts Nordvest- pynt til Fornæs. Ks. Sydlige Kattegat: Begrænses mod Sydvest ved en Linie fra Spidsen af Sjællands Odde til Hjelm. SVERIGE m De danske Farvande med de i denne Afhandling benyttede Inddelinger. Sa. Samsøpartiet: Begrænses mod Lillebælt ved en Linie fra Æbelø til Bjørns- knude og mod Storebælt ved en Linie fra Fynshoved til Refsnæs Pynt. Lb. Lillebælt. Begrænses mod Syd af en Linie fra Pölshuk paa Als til Vejs- næs paa Ærø og mod sydfynske Øgaard ved en Linie fra Hornenæs til Skjoldnæs. Sf. Sydfynske Øgaard. Begrænses mod Storebælt ved en Linie fra Turø Rev til Næs Hoved paa Langeland. Sb. Storebælt. Begrænses mod Østersøen af en Linie mellem Gulstav paa Langeland og Kappel Kirke paa Lolland, mod Smaalandshavet ved en Linie, der fra Korsør Kirke gaar over Vest-Pynten af Egholm, langs Vestsiden af 7 45 denne 0, Agersø og Omø, og fra dennes Syd-Pynt over den Syd-vesllige Omø Staalgrund til den ostlige Pynt af Onscvig paa Lolland. Sni. Smaalandshavet: Begrænses mod Østersøen udfor Bøgestrømmen af en Linie udenom Sandene til Bøgestrøm-Tønden. Su. Sundet: Begrænses mod Syd af en Linie fra Sydspidsen af Amager mod Øst. Bv. Vestlige Østersø: indtil en Linie fra Gjedser til Darsserort. Bm. Mellemste Østersø (Møen-Partiel) indtil en Linie fra Nordenden af Rügen nordefter. Bb. Bornholmske Østersø: Farvandet omkring Bornholm. Jeg har haft Lejlighed til at undersøge Ceramium-Arterne i Herbariet til- hørende Museet i Berlin og Riksmuseet i Stockholm'; endvidere har jeg i Lund haft Adgang til J. G. Agardhs Herbarium. For den Velvilje, der af de paagældende Institutioner er vist overfor mine Undersøgelser, bringer jeg herved min Tak. Oversigt over den af mig benyttede Litteratur og Exsiccatværker. ÂGARDH, J. G.: Species genera et ordines Algarum. Lund 1848 — 1863. — Epicrisis systematis Floridearura. Lund 1876. — Analecta algologica Cont. II: De typis Ceramiorum. Lund 1894. Areschoug, J. E. : Phyceæ Scandinavicæ raarinæ. Uppsala 1846—50. — Algæ Scandinavicæ exsiccatæ Ser. II. Uppsala 1861 — 79. Collins, Holden & Setchell: Phycotheca boreali-americana. Cramer, C: Die Ceramieen: Pflanzen-physiologisclie Untersuchungen von Nageli und Cramer 1857, H. 4. CriiL'an: Algues marines de Finisterre (Exsic). Derick. C. M. : Notes on the holdfasts of certain Florideæ. Bot. Gazette 1899, 28. De-Toni, j. B.: Sylloge Algarum. Patavii 1889—1905. Farlow, W. G.: Marine Algæ of New England. Washingto)i 1881. Foslie, M.: The norwegian forms of Ceramium; Kgl. Norske Vid. Selskabs Skrifter 1893. Trondhjeni 1894. Gobi: Die Rothtange des fin. Meerbusens. Mém. de l'Académie imp. des sc. de St. Petersbourg, 1877. Harvet, W. H: Phycologia Britannica. London 1846 — 1851. Hauck, f.: Die Meeresalgen Deutschlands und Oesterreichs. Rabenhorst: Kryptogamenflora 2, 1885. Janczewski: Notes sur le développement du cystocarpe dans les Floridées. Méra. de la soc. de Cher- bourg. 1876. 20. Kjellman, F. R. : Norra Ishavets algflora; Vega expeditionens vetensk. Iakttagelser, 3. Stockholm 1883. — Ora en Ceramium Art frân Gotland. Öfversigt af Kgl. Vet. Ak. Forhandl. Stockholm 1897. KÜTZING, F. T.: Phycologia generalis. Leipzig 1843. — Species Algarum. Leipzig 1849. — Tabulæ phycologicæ. Bd. XII & XIII. Kylin, H: Studien über die Algenflora der schwedischen Westküste; Ak. Afhandling. Upsala 1907. Le Jolis, A: Liste des Algues marines de Cherbourg. Mém. de la soc. imp. des se. nat. de Cherbourg. 1864. Lightfoot: Flora scotica. 1777. Lyngbye, H. C: Tentamen Hydrophytologiæ Danicæ. Kjobenhavn 1819. Oltmanns, F'r. : Morphologie und Biologie der Algen. Jena 1904—05. Rabenhorst, L. : Die Algen Sachsens, resp. Mittel-Europa's (Exsic.) Dec. 75—76. Dresden 1858. Rhinbold, Th.: Die Rhodophyceen der Kieler Föhrde, Schriften des naturw. Vereins für Schleswig-Hol- stein. Kiel 1889—91. ' udlaante til Københavns botaniske Museum. 46 8 Reinke, J: Algenflora der wcstl. Ostsee deutschen Antheils, 6ter Bericht der Korn, zur wis. Unters, der deutsch. Meere in Kiel. Berlin 1889. Rosenvinge, L. Koi.derup: Grönlands Havalger. Med. om Grönland III, 1893. Roth, A. G.: Catalecta botanica I-lll. Leipzig 1797—1806. Schmitz, F.: Die Gattung Microthamnion J. Ag. Ber. d. deut. bot. Gesellschaft. 1893, XI, Heft. 4. SvEDF.Lius, N. : Studier öl'ver Östersjons hafsalgflora. Ak. Afh. Uppsala 19Ü1. Wyatt, M. : Algse Danmonienses. Torquay sine anno. B. Bemærkninger om Ceramium-Slægtens morphologisk-vegetative og Fruktifikations-Forhold af særlig Interesse for den specielle Beskrivelse af de enkelte Arter samt en kort Oversigt over Ceramium-Slægtens Udbredelse i de danske Farvande. (Almindelig Del.) Jeg har forsøgt, om man ikke kunde anvende Antallet af Axeceller i hvert Grenstykke som Kendemærke for de enkelte Arter. Noget konstant Antal gives naturligvis ikke for hver enkelt Art, men derimod et Middeltal, som vel i og for sig karakteriserer Arten, men som dog i de aller- færreste Tilfælde lader sig praktisk anvende, eftersom det viser sig, at de fleste Arter paa det nærmeste har samme Middeltal. Naar den ene Art f. Eks. har Middel- tallet 7 og den anden 9, ligger der praktisk set en altfor stor Fare ved at anvende disse Tal. Jeg har derfor i min Fremstilling ikke i nogen særlig Grad lagt Vægt paa denne Side af Sagen. Axecellerne optræde under 2 Former, en med parallele Sider og en med Sider, der opefter nærme sig hinanden. Disse to Slags kunne findes hos samme Art og fremkomme rimeligvis som Følge af forskellige ydre Kaar [og da saaledes, at de koniske Celler rimeligvis er almindelige paa Lokaliteter, hvor Arten er udsat for stærkt Træk]. Den koniske Form er forøvrigt ikke tilstede fra 'Begyndelsen af. Da Barken spiller saa stor en Rolle for Karakteristiken af de enkelte Arter, er det nødvendigt her at dvæle lidt mere udførligt ved den. Jeg lader dog her alle ikke danske Arter ude af Betragtning. [Om Barkens almindeligere Forhold se Arbejder af Cramer (1857), Agardh (1894), Oltmanns (1904—05) samt Kylin (1907), i hvilke Hovedpunkterne af det, som her skildres, er omtalte.] J. G. Agardh er den første, som skarpt har gjort opmærksom paa det, som her meddeles om Barkens Væxt, og anvendt Barken i Systematikens Tjeneste. I nogle Tilfælde er Evnen til at vokse hos Barkcellerne i Bælternes Rand omtrent lige stærk og vi faa da, eftersom Væksten tidligt standser eller fortsættes i længere Tid, henholdsvis skarpt begrænsede Bælter med lige Rand og mindre skarpt begrænsede med Randceller, der vokser op og ned. Hel Symmetri i Forhold til Skillevæggene mellem Axecellerne forekommer dog sjældent, da den ene Del 9 . 47 (eilten den nedre eller den ovre) nf Bællet regnet fra disse Vægge altid vil være en Del fremfor den anden. I andre Tilfælde er den øvre og nedre Rand ulige begavede med Evne til at vokse, og vi faa da efter Omstændighederne Bælter, der enten vokse op- eller ned- efter eller dog stærkere i den ene Retning end i den anden. Bælter, som have Randvækst, ville i de allerlleste Tilfælde, hurtigere eller langsommere, naa hinanden og derved give Anledning til en sammenhængende Bark. Mellem denne og de skarpt begrænsede Bælter gives der en Mængde Overgangsstadier, alt efter som Bælterne ere naaede langt eller kort mod hinanden, og efter den Maade, livorpaa Bælterne vokse. Den Maade, hvorpaa dette nu sker hos de delvis barkklædte Arter, er karakteristisk for Arten; det vil vise sig, at der gør sig en bestemt Type gældende for Væksten. Saaledes er f. Ex. Cer. fruticulosnin i Særdeleshed karakteriseret ved den stærke opadløbende Tendens, som dens Bælter udvise, medens paa den anden Side en Art som Cer. Rosenvingii udmærker sig ved Bælter, der næsten ligeligt vokser i hægge Retninger. En Art Cer. circinnatum, som vi forøvrigt ikke have i vore Farvande, har atter Bælter, som fortrinsvis vokser nedad. I de Tilfælde, hvor vi have ulige Vækst, for de danske Arters Vedkommende i Særdeleshed opad- gaaende, finde vi aldrig en eller anden Grad udelukkende tilstede. Den ulige Vækst gør sig efter Alderen højst forskelligt gældende; den kulminerer sædvanligt et Stykke fra Spidsen og taber sig efterhaanden nedefter. Saaledes finde vi aldrig udelukkende Bælter med skarpt begrænset nedre Rand; kun en Zone paa Individet udviser saadanne; længere nede vokser Bælterne ogsaa fra den nedre Rand, omend stadig i mindre Grad end den øvre o. s. fr. Barkens Mægtighed, dens Tykkelse, er tiltagende med Alderen — og dette gælder alle Tilfælde, baade dem, hvor der kun er frie Bælter og dem, hvor der er delvis eller helt sammenhængende Bark fra Basis mod Spidsen. Hos de meget stærkt barkklædte Former er dog denne her frem- hævede Forskel mellem øvre og nedre Dele ikke saa fremtrædende, som hvor Barken er svag. Førend jeg dvæler nærmere ved den helt sammenhængende Bark, skal jeg kort omtale en særlig Form for Bæltedannelse, som af og til viser sig hos de ellers helt barkklædte Former. Vi finde i saadanne Tilfælde Barken afbrudt af klare Partier, sædvanlig smalle, uden at Barkrandene ud for disse i nogen særlig Grad vokse mod hinanden. Jeg tyder dette ikke som et Stadium mellem helt fri Bæltedannelse og sammenhængende Bark, men som snarere fremkaldt ved en sen Længdestrækning af Axecellerne. Den sammenhængende Bark, som er fremgaaet af Bælter, der paa en eller anden Maade ere voksede mod hverandre, udviser sædvanlig en ret stor Modsætning mellem den Del af Barken, der findes ud for eller i Nærheden af Axeccllernes Skillevægge: Diaphragmedelen og den, der findes ud for selve Axecellen, et lille Stykke fra Skillevæggen at regne, Axecelledelen. Her er Barken altid tyndere, mere storcellet end i Diaphragmedelen. Tangentiale Delinger, hvorved Barken vinder i Tykkelse, forekomme her først paa et sent Tidspunkt, medens saadanne tidligt begynde i den egentlige Bæltedel, Diaphragmedelen. Paa Grund 1). K. 1) Videii'.k. Selsk. Slii'., 7. lia-kl,.-, natiirviilfiisli. nj! ninllu-in. Afil. V. 2. 7 48 10 af Væksten er Cellerne i Axecelledelen sædvanlig slrakte paa langs — medens de i Diaphragmedelen mere har en tilfældig Længderetning eller ere isodiametriske. Den fra først af helt sammenhængende Bark, som f. Ex. hos Cer. rubrum, viser i Reglen ikke store Modsætninger mellem de nævnte Dele; de yderste Celler, der jo bestemme Barkens Karakter, er ensartede overalt. Naturligvis vil man dog ogsaa her paa Tværsnit konstatere en Forskel i Tykkelse. Ydre Kaar, vistnok navnlig Vandets Saltholdighed, bestemme i høj Grad, hvor mægtig Barken bliver udviklet, hvor mange Lag', der dannes. I Særdeleshed træder denne Forskel tydelig frem hos de fra først af helt barkklædte Former, navnlig hos Cer. rubrum, hvor vi have alle Grader mellem en tyklaget Bark med smaatcellet Yderlag og et tyndlaget og derfor storcellet Yderlag (idet nemlig Cellestørrelsen er aftagende udefter). Med Hensyn til Barkens Sammenhæng baade i de Tilfælde, hvor vi kun have Bælter, og hvor vi have sammenflydende eller sæmmenhængende Bark, maa her indskydes den Bemærkning, at de yderste Lag Barkceller altid danner aabne Pletter udfor de Steder, hvor Tetrasporangierne findes, et Forhold, der staar i Forbindelse med Tetrasporernes Udtræden. Naar Barken er flerlaget (herved ser jeg dog bort fra Tetrasporangiecellerne), fungerer sædvanligt de indre og større Celler som Magasineringsceller, for den ved Assimilationen dannede Floridéstivelse. Naar Barken kun bestaar af 1 til 2 Lag, er der ingen saadan Arbejdsdeling, idet alle Barkens Celler undtagen Tetra- sporangiecellerne kunne danne denne Stivelse. Ved dette Indhold faar Barken hos de ovennævnte svagt barkede Cer. rubrum Former (og andre tyndlagede Arter) et ganske ejendommeligt Udseende. Med tiltagende Alder fortykkes sædvanlig Celle- membranerne, og det Udseende, Axeceller, Bark og Bælter derved faar, er ofte meget forskelligt fra det, der er karakteristisk i de unge Stadier. Nogen særlig systematisk Betydning har dog disse Forandringer ikke. Foruden de Grene, der ere opstaaede ved Topcellens Vækst og Deling og som danner det for Ceramium Slægten karakteristiske gaffelgrenede Løv, optræder der sekundære Grene, som i de fleste Tilfælde udgaa fra de indre større Celler, som findes omkring Axecellernes Skillevægge, og som ogsaa kunne danne Tetrasporangier. Der er da, som det vil forstaaes heraf, et vist Forhold mellem Udviklingen af sekundære Grene og Tetrasporangiedannelsen. Nogen bestemt Regel gives dog ikke. Samme Individ vil hyppigt bære saavel sekundære Grene som Tetrasporangier — men samme Bælte vil dog sjældnere bære hægge disse Organer. I enkelte Tilfælde har jeg bemærket, at den øvre Bælterand hos Cer. strictum i Stedet for at danne Parasporehobe har dannet sekundære Grene. Udviklingen af sekundære Grene er meget forskellig hos de forskellige Arter, og den danner, naar der da ses bort fra de Tilfælde, hvor en stærk Tetrasporangie- dannelse hæmmer Grenudviklingen, et meget godt Karaktermærke for visse Arter. ' Om regelmæssige Lag, det ene uden for det andet, er der ikke Tale; naar jeg taler f. Eks. om tre Lag, vil det sige, at Barkcellerne omtrentlig forekommer i 3 forskellige Afstande fra Axecellernes Midt- linie paa langs. 11 49 Saaledes er f. Eks. Cer. arborescens karnUlcriscrct ved et meget stort Antal sekiiiuiære Grene, Cer. sirictuni derimod ved en meget ringe Udvikling af disse. Haar findes meget udbredt. Disse Organer dannes af. Barkens yderste Celler derved, at en slørre Barkcelle afgrænser en mindre, som skyder en Forlængelse ud. Haarene ere farveløse, lange og smalle, faa Mikromillimeter brede, med tydeligt protoplasmatisk Indhold. Haardannelsen er stærkest om Foraaret og om Sommeren, men ingenlunde, hvad man kunde vente, særlig almindelig hos hidivider paa lavt Vand. Tva>rl- imod, i en Dybde paa over 10 Meter kunne vi endnu finde rigelig Haardannelse, ja endog paa 20 Meters Dybde er Haar endnu ikke ganske sjældne. Hvilke ydre Faktorer, der er de egentlig bestemmende for Haarenes Fremkomst, skal jeg ikke indlade mig paa at gruble over. Lyset spiller formodentlig en vis Rolle, men andre Faktorer ere vistnok lige saa vigtige. Haardannelsen giver ikke gode Artsmærker. Hos visse Arter: Cer. tenuissiiniim, delvis Cer. nibriiin og Cer. arborescens, har jeg fundet særegne, nyre- eller hjærleformede, indholdsrige, lysbrydende, farve- løse Barkceller (Fig. III) i de yderste eller næstyderste Lag af Barken. Indholdet af disse Celler farves svagt gult ved Chiorzinkjod; Osmiumsyre giver ingen Reaktion; derimod faar man en rød Farve frem ved Millon's Reagens. Da de almindelige Barkceller ikke farves nær saa meget, indeholder disse Celler altsaa særligt store Mængder af Æggehvidestoffer. Betydningen af disse Celler er mig ubekendt. I Litteraturen er vistnok lignende Dannelser kun beskrevne for Turnerella og Criioria arctica's^ Vedkommende. Antithamnion's „Blasenzellen" er vistnok noget andet". Farven er ret forskellig hos de forskellige Arter. Nogen sikker Vejledning til Artsbestemmelse giver Farverne dog ikke, i Særdeleshed da de kunne paavirkes af Sollyset, bleges. Lyse Farver, stærk Afblegning, finde vi s;edvanlig hos Overflade- individer; mørkere Farver er karakteristisk for Bundformer, Skyggeindivider. Alle de Individer, der forekomme i Aarets mørkeste Tid, er dog, hvad enten de findes paa lavt eller dybt Vand, meget mørkt farvede, i torret Tilstand sorte eller næsten sorte. Hvor enkelt end Cerani/um-Arterne ere byggede, saa frembyder de dog fra Art til Art saa mange morphologiske Forskelligheder, at disse, hvor vi have med typiske Individer at gøre, ofte alene er tilstrækkelige for det øvede Øje ved Bestem- melsen. Disse Forskelligheder kommer frem i Grenvinklernes større eller mindre Udspærrethed, i Internodiernes Længde, i den mere eller mindre tydelige Dikotomi o. s. fr. Særlig karakteristisk er ofte Udviklingen af Hovedstammer, Grenendernes Forhold, om de ere indkrummede eller rette. Udviklingen ai' Cijstokarpier har jeg ikke forfulgt (smlgn. her Janczewski, 1876). De anlægges vel altid lateralt, men blive ofte med Væksten mere eller mindre ' L. Kolderup Ro.senvinge: Grønlands Havalger. Medd. om Granland. Bd. III, pag. 784 og 81Ö. - Nestler: Die Blasenzellen von Antithaninion plumula. Wiss. Meeresnnters. 1898. N. F., ,3. Abt.: Helgoland. 7* 50 12 endeslillode. De syslemaliske KaraU lerer, man i saa Henseende har villel danne, synes mig dog ganske ubrugelige. Jeg linder ikke, al Cyslokarpierne i mindsle Maade frembyder nogpt, hvorpaa man kan støtle Arlskarakterer. Ej heller finder jeg, at de Svøbgrene, som altid støtter Cyslokarpierne, kan anvendes i samme Ret- ning. Cyslokarpierne ere hyppigere forekommende hos visse Arter end hos andre og sjældnere end Tetrasporangier og Parasporehobe, hvor saadanne forekomme. Antlieridier eller bedre Spermatiemoderceller (Spermogonier) (Fig. I,) da disse Celler ikke findes i formede Dannelser, forekomme paa andre Individer end paa de cystokarpiebærende ; Ceramium Arierne er saaledes tvebo. Fig. I. /. Bælte med Spermatiemoderceller (Ger. diaphanum), 2. Spermatiemodereellernes Korbindelse med Barkcellerne. 3. Sammenvoxede Spermatiemoderceller. 4. Spermatiemoderceller sete fra oven (3, 3 & i. Ger. Rosenvingii). Naar Spermatiemodercellerne skulle dannes, deler Barkens yderste Lag sig stærkt og sædvanligt da ved Delinger vinkelret paa Overfladen. Hver af de herved fremkomne yderste Celler, der altsaa staa vinkelret ud paa Overfladen, danner paa sin Yderside een eller liere Spermatiemoderceller. Disse vokse ud fra de nævnte Celler og afgrænses fra dem ved Væg (Fig. I. 2). Sædvanlig findes disse Celler sammen i smaa Grupper eller større afgrænsede Partier; kun i ganske enkelte Tilfælde har jeg set hele Individer dækkede fra nederst til øverst med dem. Spermatiemodercellerne frembyde vistnok hverken med Hensyn til deres Form eller Udbredelse paa Individerne Arlskarakterer. At Antheridierne saa sjældent blive 13 51 fundne, skyhits vislnok niusl ilun Onisla'Mcliglicd, al man tørst kan iagllagc dem med Mikroskop. De anlheridiebærende Individer bliver derfor ikke i samme Grad samlede som de cyslokarpiebærende. Den kønsløse Formering ved Sporer finder Sled paa 2 Maader 1) ved Tetra- sporer og 2) ved P a r a s p o r e r. ' Fig. 11. Parasporchobe (Cer. cliaphanuni). 1 1 ser man deii første Begyndelse; de to svagt punkterede Celler ved den øvre Rand viser den ganske unge Parasporehob. Medens Tetrasporer forekomme hos alle Arter, optræder Parasporerne kun hos enkelte. Tetrasporerne opstaa som bekendt i visse indre Harkceller nær Diajibrag- merne og kunne efter Individets Art og Kraft optræde i flere eller færre Rækker. ' Navnet Parasporer skyldes Schmitz. o 52 14 Hos Alter med smaa Bælter findes dog aldrig mere end een Række. Efter min Mening bør man ikke lægge altfor stor systematisk Værdi ind i Antallet af Rækker. Hos enkelte Arter, af danske dog kun Cer. teniiissimiim, komme Tetrasporan- gierne ved særlig Vækst af Bæltet til al rage stærkt frem. Hos de andre kan man blot tale om mere eller mindre indsænkede Tetrasporangier. Tetrasporerne træde i sidstnævnte Tilfælde ud gennem de tidligere omtalte Aabninger i Barken. I en- kelte Tilfælde har jeg bemærket en Art Monosporedannelse (Cer. diaphanum)'. I Modsætning til Tetrasporerne dannes Parasporer ne, der blandt danske Arter kun findes hos Cer. diaphanum og Cer. strictum, kun fra de yderste Celler i Barken, hyppigst fra de Celler, der ligger nær Bælternes øvre Rand, eller de øverste Rand- celler selv. Den Celle, som er den første Begyndelse til Parasporehoben, strækker sig lidt frem foran de andre Barkceller og fortykker sin Membran noget (Fig. II. 1 & 2). Den deler sig derpaa, uden at Spor af Telradedannelse kan paavises, ved uregel- mæssigt stillede Vægge i et ofte meget stort Antal Sporer (Fig. II. 3). Vi faa da til- sidst en Cystokarpie-lignende Dannelse af mere eller mindre uregelmæssig, afrundet lappet P'orm, en Samling Sporer liggende uordnet indenfor en fortykket hyalin Fællesmembran. Parasporehobe kunne ved flygtigere Undersøgelse forvexles med Cystokarpier, men adskiller sig fra disse 1) ved Stillingen, 2) ved Mangelen af Støttegrene (som dog Cystokarpierne af og til kunne mangle), endelig 3) ved deres gruppevise Ojjtræden. Paraspore- og Tetrasporedannelse kan foregaa samtidigt paa samme Individ og i samme Bælte ^. Ceramium Arterne forekomme saavel paa lavt som paa dybt Vand. En enkelt Form tilhører den egentlige Litoralregion eller forekommer paa lavt Vand: C. diaphanum ; andre er bundne til noget dybere Vand, f. Eks. Cer. strictum ; de fleste er dog vistnok, naar den øverste litorale Region (Fjæi'en) undtages, ligegyldige for større eller mindre Dybde, omend Forskelligheder i denne Retning kan have Betyd- ning for deres morphologiske Udvikling. Arterne forekomme dels som Epiphyter, dels paa dødt Substrat, og det er da saaledes, at visse Arier fortrinsvis ere epiphy- tiske, medens de fleste ere ligegyldige med Hensyn lil Substratet. lovrigt vil jeg, som allerede tidligere ntevnt med Hensyn til Algesamfundene og Ceramium Arternes Stilling i dem, henvise til Dr. Kolderup Rosenvinges fremtidige Skildringer heraf. De fleste Ceramium Arter forekomme kun i Aarets lyse Tid og have da i Særdeleshed deres Maximum i Sommermaanederne. Her i vore Farvande er del vistnok egentlig kun Cer. rubrum og Cer. fruticulosum, som træfles om Vinteren og tidlig paa Foraaret. De danske Farvandes ulige Natur belinger en ulige Fordeling af de enkelte Arter indenfor det hele Omraade, og det er da rimeligvis den forskellige Salt- holdighed, som findes i de forskellige Dele af vore Farvande, — som jeg forøvrigt ikke skal dvæle ved her, idel jeg henviser til Dr. Kolderup Rosenvinges Arbejde, — som spiller den væsentligste Rolle. 1 Smgl. Gobi 1877 Tab. fig. 8. - Smgl. Kylin, der har bemærket det samme pag. 175. 15 53 En Ting er forunderlig, naar vi belragter Udljiedelsesforholdene, og det er den, at flere Arter, som Ccr. diaphaniiin ', Roseiwingii, iivke er fundne i nordlige Kattegat (eller Limfjorden), da de jo dog forekommer andetsteds, hvor Vandet har samme Saltholdighed som disse Farvande. Aarsagen hertil er mig ubekendt; om Indsam- lingsmangler kan der vel ikke være Tale, da de paagældende Dele er særdeles vel undersøgte. — Udbredte over alle danske Farvande er Cer. rubrum og Cer. tenuissi- mum. Cer. frudcnlosum forekommer kun i Skagerak, nordlige Kattegat og Limfjorden — den er i det Hele vistnok en Form, der tilhører nordligere Farvande. Den med denne Art beslægtede Cer. Areschougii gaar derimod ret sydligt gennem Katlegat ned i Bælterne. Cer. strictum's nordligste Lokalitet er i Limfjorden, Cer. diaphanum's ved Anholt ; bægge gaa de ind i Østersøen. Cer. Rosenuingii har omtrent samme Udbredelse som Cer. diaphanam, kun forekommer den ikke i den midterste og vestlige Østersø. Den med Cer. Rosenuingii beslægtede Cer. arborescens gaar nord- ligere end denne, helt op i nordlige Kattegat, men naar ikke langt ind i Øster- søen -). Cer. vertébrale er paa en enkelt Lokalitet nær kun bemærket i Østersøen. Cer. rubrum forandres morphologisk meget efter som den kommer sydpaa; noget lignende gælder tildels Cer. diaphanum; de øvrige Arter synes ikke at forandres videre indenfor deres danske Omraade. Nøgle til Bestemmelse af de danske Ceramium Arter. 1. Barken overalt adskilt i skarpt begrænsede Bælter 2 — Sammenhængende Bark eller Overgangstilfæ.lde mellem Bæltedannelse og sammenhængende Bark 3 2. Barken uden nyre-hjærteformede, lysbrydende Celler 4 — Barken med saadanne Cer. lenuissimum 3. Som Regel ensartet Bark over det Hele; af og til klare Linier paa tværs nær Spidsen Cer. rnbrnm — Bark mere eller mindre ensartet, 1) snart med Bælter, der kim allerøverst ere skarpt begrænsede, men længere nede ere mere eller mindre sammenflydende, 2) snart uden egentlig Bæltedannelse, med tydelig uensartet Bark frem- gaaet ved Sammensmeltning af Bælter, eller 3) med de fleste Bælter skarpt begrænsede, kun de nedre opadløbende. . . 5 4. Smaatcellet Yderbark; Parasporer til Stede, Bælteafstand 3 — 4 Gange Bæltehøjden Cer. diaphanam — Storcellet Yderbark; Parasporer til Stede eller ikke til Stede.. 6 5. Ikke noget Steds helt sammenhængende Bark 7 — Sammenhængende Bark forneden eller højt op 8 6. Axeceller meget lange, ofte indtil 10 Gange Bælternes Højde; Parasporer til Stede Cer. slriclum ' Med Hensyn til Cer. diaphanum's Udbredelse er det muligt, at den ogsaa har hjemme i Limfjorden, idet to Individer, som ere fundne ved Nykjobing (F. Borgesen), muligt hører til denne Art. ' Aiigaaenilc Cer. Desloiigehampii se lifterskrifteii. 54 1(5 6. Axeceller næppe mere end 5 — (5 Gange Bælternes Højde; Parasporer ikke til Stede 9 7. Bælterne kun svagt opadløbende forneden Ger. diaphaniim forma corticatiila eller Cer. diaphaniim (Hovedformen) — Bælterne opadløbende næsten overalt Cer. friiticulosum forma? Cer. Areschougii pro parte? 8. Bælterne mest opadløbende 10 — Bælterne baade opadløbende og nedadløbende 11 9. Bælter indtil omtrent lige saa høje som brede; rette Grenender Cer. Deslongchampii — Bælter sædvanlig bredere end høje, Grenender mere eller mindre rette — ofte indtil 30 — 40 Axeceller i hvert Grenstykke Cer. vertébrale 10. Grenenderne haarfine, ofte rette; lyse Farver; altid med tydelig Bæltedannelse mod Spidsen; Habitus som Cer. strictum o. 1. Cer. Areschougii — Grenender ikke haarfine; mørke Farver; Habitus som Cer. rubrum Cer. fruticulosum 11. Ingen særlig Udvikling af sekundære Skud Cer. Rosenvingii — Stærk Udvikling af sekundære Skud Cer. arborescens C. Beskrivelse af de enkelte Arter. (Speciel Del.) a. Barken med skarpt begrænsede Bælter eller med svagt opadløbende Bælter forneden. I. Antallet af Axeceller i hvert Grenstykke gennemsnitligt 7 15. 1. Ingen Parasporedannelse. Ceramium tenuissimum (Lyngbye) Agardh. Fig. III. Tab. I, Figl. Syn.: Cer. diaplianum var. tenuissima Lyngbye, Tent. Hydr. Dan. pag. 120, Tab. 37, B. 4. J. G. Agardh, Spec. gen. et ord. Alg. Vol. II, 1 pag. 120. Lyngbyes Herbarium: Hofmansgave, Novbr. 1812 og Gilleleje -s 1833. Crouan: Algues mar. de Finistère Nr. 168 (Exemplaret i Bibi. bot. i Lund). Areschoug: Algæ Scandinavicæ exsic. Ser. nov. Nr. 13. Individerne meget regelmæssigt gafifelformet forgrenede, dannende store kraftige Vegetationer paa indtil 15 Ctm. i Diam. Grenenderne altid indkrummede, sete under Mikroskopet med udadtil ejendommelig takket Rand (Fig. III. 1), en Karakter, som blandt de danske Arter kun findes hos denne Art, og hvorved den straks skelnes fra Cer. strictum og lignende Former, der habituelt minde i høj Grad om den. Sekundære Grene cre ikke særlig almindelige. Bælterne ere allid vel afgrænsede uden 17 55 Spor af Væxt opad eller nedefler, med slore yderste Barkceller, sædvanlig noget mindre høje end brede. Axecellernes Længde eller bedre Afstanden mellem Hæl- terne meget stor i Forhold til Bælternes Højde. Nogle Maal ville oplyse om dette. Bæltehøjde Bæltebredde Afstand 6. Grenstykke fra Spidsen 72 « 88 // 990 n En Række Maal for samme Plantes Vedkommende ser saaledes ud: (5205 Lokken) Bæltehøjde Bæltebredde Afstand 1. Grenstykke efter forceps 27 /i 44/^ 22« 2. — — 33 - 49 - 44 - 3. — — 38 - 55 - 72 - 4. — — 33 - 55 - 220 - 5. — - 33 - 72 - 275 - ubestemt nær Basis 82- 61- 800- Axecellernes Ydervægge ofte meget tydeligt parallele. Antallet af AxeccUer i hvert hiternodium (Grenstykke) er sædvanlig 9 — 11. Som allerede omtalt i den almindelige Oversigt udmærker Ccr. tenidssimiim sig ved Tilstedeværelsen af ejendommelige, lysbrydende, farveløse, nyre- eller hjærte- Fig. 111. Cer. tcmiissimtim. i. Grenspidscr. ?. Tctrasporangiiim o« Bælte med 2 af de ojonddmmeligt Ijsbiydende Barkceller. 3. Unge Balter, hvoraf det nedre viser en af de lysbrydende Celler. I) K. 1). Viili'ilsk. Selsk. .Skr-, 7. li.-eUke, iialurviilciisU. n^ ni:illn-ni. AM, V. 2. 8 56 18 formede Barkceller (Fig. III. 2, 3). Disse omdannede Barkceller reagere ret slærkt for Æggehvidestoffer, men indeholder ikke Floridéslivelse og findes i Særdeleshed i de yngre Bælter i et Anlal af 2—3 i det yderste Barklag. Med Alderen synes de at forsvinde eller forandres. Disse Celler danne, naar Hensyn tages til de danske Arter, et godt Kendetegn paa Cer. lenuissimiim. I andre geografiske Omraader er denne Karakter mindre brugelig, da vi genfinde disse Celler hos Cer. gracillinmm. Haar er overmaade hyppige. Farven er paa unge, ikke blegede Individer skiden blaarød. Tetrasporangier forekomme ret hyppigt , sædvanlig 1 (sjældnere 2) i hvert Bælte, enradet ordnede paa den ydre Side af Grenene, normalt stærkt fremragende, støttede af særlige Barkdannelser (Fig. III. 2). Cystokarpier har jeg kun bemærket 1 Gang ; Antheridier slet ikke. Naar Kylin (1. c. pag. 175) angiver at have set Parasporer, maa dette vistnok bero paa en Fejltagelse. Ceramium teimissimiim er væsentlig en Sommerform (Expl. tagne i Juni — Sept.); et enkelt Individ er dog taget i Januar. Den forekommer saavel paa lavere som dybere Vand (dybest ca. 23 Meter), vistnok udelukkende epiphytisk. Arten er tagen paa 32 Lokaliteter' (med 36 Numre) i alle danske Farvande undtagen Nord- søen, Smaalandshavet, den vestlige og bornholmske Østersø, men maa antages ogsaa at kunne findes i disse Farvande. Naar Gobi (1877) angiver at have fundet Cer. gracillimum i Østersøen, maa det antages, at han har haft at gøre med Cer. tenuissimiim eller Cer. striclum. De nordligst forekommende Individer (Hirshals, Fladen) ere gennemgaaende kraftigere og mørkere farvede end de sydlige, men om morphologiske Forandringer er der dog ikke Tale. 2. Parasporer til Stede. «. Afstanden mellem Bælterne højst indtil 4—6 Gange længere end Bælternes Højde. Ceramium diaphanum Harvey et Agardh (Tab. I, Fig. 2, 4 og 5; Tab. II, Fig. 4). Ceramium diaphanum Roth i Harvey: Phycologia brit. Tab. 193; Ceramium diaphanum (Lightfoot) J. G. Agardh: Sp. gen. et ord., Vol. II, pars 1, pag. 125; Epicris: pag. 28. Cer. diaphanum (Lightfoot) Roth hos Hauck, Foslie, de-Toni o. a. Exsic: Crouan: Algues mar. de Finistère Nr. 171 (Exempl. tilhørende det bot. Bibliothek i Lund). Areschoug: Algæ scand. exs. Ser. nov. Nr. 208 nederst. Wyatt: Algæ Danmonienses Nr. 87. Phycotheca boreali-amer. Nr. 846 a & b (3 Exempl.). Naar jeg har sat Harveys og Agardhs Navne efter Artsnavnet Cer. diaphanum, saa er det, fordi jeg refererer de F"ormer, jeg her henfører til denne Art, til disse ' Lokaliteter, der ligge nær ved hinanden, ere regnede under et. 19 57 to Forskeres Beskrivelser og Alhildning. Del er muligt, at Lightfoots og Roths Navne bor tilføjes, men jeg maa tilstaa, at jeg, naar jeg undersøger Beskrivelserne hos d'isse to sidste Forskere, ikke kan se andet, end at det er ganske uklart, hvad de have ment. Deres Beskrivelser passer ligesaagodt til Cer. teiuiissiiniim, Cer. strictiim, Cer. Areschoiigii og fniticulosum o. m. a. som til Cer. diaphanuni. Prioriteten af deres Navne kan muligvis dog bevises ved Originalexemplarer fra deres Haand og jeg lægger derfor ikke stor Vægt paa denne Side af Sagen. Ceramium diaphanuni hører efter min Opfattelse til de meget vanskelige Arter, idet den kan variere saaledes, at den kommer til snart at ligne Cer. Deslonychampii snart Cer. strictum; endelig har den Berøringspunkter med Cer. Areschoiigii og friiliciilosiini. Her i denne F'orbindelse, med Hensyn til de her behandlede Arter, vedrører Slægtskabet med Cer. strichim os mest og jeg skal da her kortelig gøre -\, Fig. IV. /. Bælte af Cer. diaplmitiim. 2. Bælte af Cer. strictum (I og 2 samme Foistonelse). 3. Cer. stricliim med Tetrasporangium og Parasporehob i samme Bælte. i. Bælte af Cer. diaphanum. Rede for, hvorfor jeg ikke som Foslie har forenet bægge disse Arter til een'. Ved nøjagtig Undersøgelse af en stor Mængde Individer ikke blot fra vore P'arvande, men ogsaa fra andre, mener jeg at have fundet, at der er visse Karakterer, som ' Cer. diaphanum forma typica og forma stricta. 8* 58 20 ikke i nogen sturlig Grad er underkastede Variation og som ikke flyde over i hin- anden, hvormeget end det morphologiske Habitus, der udmærker disse to Former, kan forsvinde, hvormeget de end ligne hinanden. Hos Cer. diaphanum vil sædvanlig Højden af Bælterne i de nedre og mellemste Dele være større end ca. 120 fi; hos Cer. strictiim vil denne Højde i de samme Partier sædvanlig være lige omkring dette Tal eller hyppigt lavere (Fig. IV. 1 & 4). Barken hos Cer. diaphanum er fler- laget med sniaa yderste Barkceller; hos Cer. strictum er Barken i hvert Fald i de øvre og midterste Dele faalaget (1 højst to Lag) dannet ofte af noget større Celler end hos Cer. diaphanum (Fig. IV. 2). Kun hos en bestemt Form af Cer. diaphanum vil Afstanden mellem Bælterne være 5—6 Gange Bæltehøjden — hos Cer. strictum vil dette Forhold være det normale og større Afstande ikke sjældne; derimod vil mindre ikke forekomme. løvrigt indrømmer jeg, at der er Tilfælde, hvor Afgørelsen kan være vanskelig, men der er jo dog ikke noget i Vejen for, at to Arter kan variere ind i hinandens Karakterer, og to Arter er efter min Opfattelse Cer. dia- phanum og Cer. strictum. hidividerne af denne Art ere af forskellig Størrelse, ofte meget store, indtil 15 — 20 Ctm. i Diameter — hos danske Former dog næppe mere end 10 Ctm. — Endeforgreningerne mere eller mindre indkrummede. De fleste Individer, jeg har set fra andre Lokaliteter end danske, ere sædvanlig udstyrede med en stor Mængde sekundære Grene; af de danske Individer have kun faa været forsynede meget rigt med saadanne. Middeltallet af Antallet af Axeceller i hvert Grenstykke er omtrent 8,5. Følgende Oversigt oplyser om Leddenes Længde. Bæltehøjde Bæltebredde Afstand 1. Grenstykke efter forceps' .... 61 /^ 110 /i 3'S fi 2. — — .... 83 - 138 - 55 - 5. — — .... 138 - 275 - 249 - Nedre Dele 165 - 300 - 440 - — 121 - 176 - 204 - — 275 - 375 - 660 ■ — 165 - 220 - 600 - Hos forma corticatula kan Afstanden mellem Bælterne slige til ca. 700 /i, saaledes at Forholdet mellem Bællehojde og Afstand [ 1 bliver noget mindre end i sidste anførte Tilfælde. Naar Barken er bleven nogenlunde udviklet, hvilket vil sige et Stykke nedenfor Spidsen, er den altid flerlaget" med smaalcellel yderste Lag. Den er heri forskellig fra den, vi finde hos Cer. strictum, som kun sjældent, naar undtages de allernederste Dele, er flerlaget paa samme Maade som hos Cer. diaphanum. — De sidst dannede Barkceller vil sjældent overskride 12« i længste Diameter. De nederste Bælter har undertiden udpræget Tendens til at voxe opefter, saaledes at vi faa Bæ'lter, der ' Forceps betegner den yngste GalTelgrening. -' De indre tetrasporangiedannende Celler er ikke regnede med. 21 59 hore til samme Kalegori som de, der er karaklerisliske for (k-r. ArcschoiKjii og Cer. friiticiilosum. Axecellernes Form med Alderen ofte konisk. Haar meget almindeligt til Stede. Farven i ren Tilstand i Retning af det rustrøde. Tetrasporer og Parasporer ere de hyppigste Forplantningsorganer og optræde omtrent med lige stor Hyppighed. Tetrasporangierne forekomme oftest kun i een Række. Cystokarpier ere sjældne, altid (?) omgivne af Svøbgrene, side- eller endestillede; Antheridier har jeg kun bemærket faa Gange. Cer. diaphaniim er en udpræget Littoral- og lavt Vands Form voxende dels paa Alger, dels paa Stene og Bolvæker o. 1. Den træder herved i Modsætning til Cer. strictiim, der altid vil findes paa noget dybere og dybt Vand, noget der taler for, at det er to adskilte Arter, men som dog ikke er noget Bevis derfor, idet jo Cer. strictiim kan være en Form af Cer. diaphaniim tilpasset til dybere Vand. Den forekommer kun sjældent i Vintermaanederne, men har sin Hovedudvikling i Maa- nederne April— Oktober. Jeg har fundet det hensigtsmæssigst at skelne mellem 4 vel karakteriserede Former, hvortil kommer en foreløbig mindre bekendt Form (5). 1. Cer. diaphanum forma typica a; forma typicissima in maribus danicis. (Tab. 1, Fig. 2 og 4.) Det karakteristiske ved denne Form er dels den rigelige Udvikling af sekun- dære Grene, dels en tydelig Tendens til at danne Hovedstammer i Forgreningen, saaledes at der ofte kommer en Slags fjerformet Grendanuelse frem; endelig er Gren- spidserne sædvanlig stærkt indkrummede. De nedre Bælter vise undertiden Tegn til at ville voxe opefter. Harveys Fig. 193 i Phyc. brit. giver et ret godt Billede af denne Form ; kun skulde Bælterne maaske gøres noget højere og Axecellerne noget kortere. Helt typiske er strængt taget kun Exemplarer fra Bm: Rødvig (6005); Faxe Ladeplads (5709); Su: Ellekilde Strand (^Forf.) og Lb: Rosenvold Havn (1735). De øvrige, hvoraf den nordligste er taget i Anholt Havn og den sydligste i Gjedser Havn, (øvrige Lokaliteter er i sydlige Kattegat, Samsøpartiet, Storebælt og Sundet) danne mere eller mindre tj'delig Overgang til forma modi/icata. 2. Cer. diaphanum forma strictoides. (Tab. 11, Fig. 3, subf. ß.) Denne Form slutter sig tæt op til typica, men adskiller sig dels ved sit mere regelmæssigt dikotome strictumagtige Habitus, dels ved ofte at have meget store Bælteafslande (indtil 5 — 6 Gange Bæltehojden) (indtil 700 «). Hos subforma corli- catula er Bælterne forneden meget tydeligt opadvoxende. subforma a. Enkelte Steder: Ks: Holbæk (913); Lynæs Havn (2604); Kjerleminde (1461); Sb; Rudkjøbing (1157); Sm: Venegrund (5980) (2—3 Fvn.!!!);Bm: Ostersø ved Møen (Carol. Rosenberg). Formen fra Venegrund er ikke ganske littoral. 60 22 Her stiller jeg endvidere nogle Ivivlsonime Former tagne paa meget lavt og stille Vand paa 3 Steder Ks: Mellem Bognæs og Boserup (4678), Holbæk (828) og Sb: Nakskov Fjord (Th. Mortensen). Subforma ß [corlicatula (Kylin)? (Kylin Tab. 7, 3)]. Denne Form identificerer jeg omend med Tvivl med den af Kylin (1907) op- stillede Art Cer. corticatiiliim'. Al jeg ikke opstiller den som Art, ligger deri, al den Karakter, hvorpaa den særlig opstilles, de svagt opadløbende Bælter, genfindes om end i ringe Grad hos Cer. diaphanum, fra hvilken Art den iøvrigl ikke er til at skehie. Den er funden i Sundet i Helsingsørs Havn (1862 og C. Rasch 313), paa Køben- havns Inderrhed (298) og ved Dragør (4699) samt nord for Ærø i sydfynske Øgaard (5932). 3. Cer. diaphanum forma modificata (Tab. I, Fig. 3). Det, der karakteriserer denne Form overfor typica, er overvejende Mangelen af sekundære Grene eller den ringe Udvikling af disse og den sjældnere Forekomst af Hovedstammer. Fra „strictoides"' skelnes den dels ved ovenanførte, dels ved den mindre regelmæssige dikotome Forgrening og de typiske Bælteafstande. Kan blive meget kraftigt udviklet. Denne Form er funden paa 30 Lokaliteter i sydlige Kattegat, Samsøpartiet, Sundet, Storebælt, sydfynske Øgaard, mellemste og bornholmske Østersø. Enkelte Exemplarer stamme frai November Maaned. Flere Individer vise Overgang til forma radiculosa (Tab. I, Fig. 5). Nogen Afsvækkelse af Formen i Østersøen kan ikke paavises; tværtimod. 4. Cer. diaphanum forma radiculosa (Grunow) (Tab. II, Fig. 4). Syn.: Cer. radiculosum Grunow; Hauck: Meeresalgen ; pag. 106. Det mest karakteristiske ved denne Form er den tætte sammenfiltrede Væxt. Vegetationerne bestaa ofte af en tættere nedre Del og enkelte fra denne fremragende Skud. Sekundære Grene almindelige. Væxten er i det Hele svag og Stammerne tyndere end hos de andre Former. Kun funden paa enkelte Lokaliteter ved Bornholm og Christiansø i Østersøen. (Mon Kjelmans Form fra Gotland (Kjelman 1897) er lig denne Form?). Den nordligste Lokalitet, som Cer. diaphanum i Folge det foregaaende er funden paa, er Anholt Havn. Der findes imidlertid i Materialet nogle Individer fundne ved Nykjobing, Morsø (F. Børgesen 35), som muligvis er at henføre til Cer. diaphanum. De ligner noget Cer. elegans, men Sandsynligheden taler dog for, at vi her virkelig ogsaa have med Cer. diaphanum at gøre, og denne Arts Udbredelse bliver da mere Ibrstaaelig. Fuldt saa vel udviklede som andetsteds forekommende diaphanum Former er ') Mine lirfaringer i Somineien 1908 have bragt mig paa den Tanlie, om ikke Cer. corticatulum Kylin er identisk med en svagt barket Korm af Cer. Areseliougii. 23 61 de danske ikke; men nogle af dem (forma typica) har dog Ariens typiske Præg over sig. Majoriteten af de i de midterste og sydlige P'arvande forekommende Former tilhører Formen ^modificata'\ der vel nok hyppigst betegner en Form fremkommen som Følge af ringe Saltholdighed, men ikke nogen særlig svækket Form, tværtimod. Snarere synes Cer. diapbaimm i Østersøen at give Anledning til nye og kraftige Former: Arten naar vistnok langt ind i Østersøen; den er jo endnu hyppig ved Bornholms Kysl. [5. Cer. diaphanum forma zoslericola. Under delle Navn har jeg noteret nogle meget daarlig udviklede, meget diko- tomt grenede Exemplarer, som minder om Le Jolis's Cer. strictiim forma zoslericola (Algues marines de Cherbourg Nr. 123). De ere fundne ved Slubbekjobing (3283), ved Bogø (3309), i Guldborgsund (1081—1093), samt ved Livø (3821) og Sprogø (3234) paa Chorda Filum. Jeg kan ikke ganske anerkende dem som Former af Cer. strictum; men jeg anser endnu Spørgsmaalet for at være aabent]. ß. Afstanden mellem Bælterne indtil 10 Gange længere end Bælternes Højde. Ceramium strictum Grev. el Harvey (Tab. I, Fig. 6 og 7; Tab. II, Fig. 1). Harvey : Phyc. brit. Tab. 334. J. G. Agardh: Spec. gen. et ord. alg. Vol. II. 1 pag. 123; Epicrisis pag. 27. Individerne af forskellig Størrelse (højst ca. 15 Clm. i Diam.), i de fleste Til- fælde lidet kraftige med meget tynde Celletraade, lyst eller mørkt blaarøde af Farve, sædvanlig udpræget dikotomi forgrenede, uden særlig fremtrædende sekundær Grendannelse. Grenspidserne mere eller mindre indkrummede uden nogen yderlig- gaaende Tendens i den ene eller anden Retning. Barken svag, uden det for Cer. diaphanum karakteristiske, smaatcellede Yderlag (Fig. IV. 2), ret storcellet. Medens vi hos Cer. diuphamim kan tale om 3 — 4 Lag, naar vi regner de inderste store Celler med, faar vi her næppe at gøre med mere end 2. Bælteranden er altid skarpt begrænset. Bælternes Højde naar næppe mere end 110//. Afstanden mellem Bælterne er, som tidligere nævnt, ofte meget stor. I de mellemste og nederste Dele af Individerne vil den ofte naa en Størrelse, der er en 8—10 Gange Bælternes Højde. Følgende Tal oplyser om Forholdet mellem Bælternes Højde, Bredde og indbyrdes Afstand i de nedre Partier. Exemplarer fra B. H. B. Br. B. A. Nissum Bredning 83 /^ 110 // 440 // Lillebælt ' 65 - 140 - 270 - Sjællands Rev 110 - 165 - 720 - Flinlerenden 110 - 140 - 600 - Davids Grund 87 - 138 - 800 - Sallhammer Rev 55 - 110 - 550 ■ 62 24 Denne tilfældige Saninienslilling lor dog ikke anliiges al give Gennenisnits- maalene i de respektive Farvande. Axecellerne ere dels cylindriske — dels koniske. Haar er ikke særlig rige- ligt tilstede. Telrasporangier og Parasporehobe forholde sig ganske som hos Cer. diapbaniim, kun forekomme de første paa Grund af Bælternes mindre Højde i kun een Række. Parasporehobe ere hyppigere end Telrasporangier. Cystokarpierne frembyde intet særligt bemærkelsesværdigt; de ere side- eller endestillede, omgivne af flere eller færre Svøbgrene. De ere kun iagttagne 1 Gang; Antheridier slet ikke. Cer. strictum er som Cer. diaphanum og de fleste andre Ceramium Arter ude- lukkende knyttet til Aarets lyseste Tid — de ere fundne i Maanederne April— September. Forplantningsorganer ere fundne i Maanederne Maj — September. I Modsætning til Cer. diaphanum forekommer Cer. strictum ikke i den strængt littorale Zone. Den er vistnok altid bundet til noget dybere og dybt Vand (3— 16 Meter) - formodentlig udelukkende som Epiphyt. Jeg mener, at Cer. strictum i de danske Farvande optræder under to Former, hvoraf den ene, forma vera, danner Hovedmængden; den anden, forma stricto-tenuis- sima, har kun underordnet Betydning. Cer. strictum forma vera (Tab. I, Fig. 7; Tab. II, Fig. 1). Grenenderne ikke udspærrede. Funden paa c 50 Lokaliteter i Limfjorden, sydlige Kattegat — Samsøpartiet — Sundet og Bælterne, sydfynske Øgaard, Smaa- landshavet, vestlige og midterste og bornholmske Østersø. Mangelen paa Lokaliteter i Skagerak, nordlige, midterste (og østlige) Kattegat er paafaldende, da Arten jo angives ellers at forekomme paa Steder, hvor Vandet er stærkt salt. I Limfjorden er den funden 3 Steder: 1. ved Mullerne i Nissum Bred- ning, 2. udfor Eierslev og 3. ved Nørre-Sundby, altsaa baade i den vestlige, midterste, og østlige Del. Derpaa faa vi en Lokalitet ved Østspidsen af Anholt, medens Far- vandet nord for Limfjordslinien ingen kan opvise ^ De nordligste Lokaliteter efter Anholt er ved Sjællands Odde og Lynæs og nu tager Lokaliteternes Hyppighed stærkt til — Østgrænsen i Østersøen ligger aabenbart langt imod Øst. Mulig er det denne Form, som Gobi omtaler under Navn af Cer. (jracillimum. Ccram. strictum forma stricto-tenuissima (Tab. I, Fig. 6). Denne Form udmærker sig i særlig Grad ved mere udspærrede Grenspidser og en meget elegant Væxt. Den er meget nær forbunden med Hovedformen, samt minder meget om de Side 22 omtalte Indvandsformer af Cer. diaphanum. Ligeledes har den en stor habituel Lighed med Cer. tenuissimum. Lok. Sb: Kjerteminde Havnemole (1454,1484); Strandby Stenrev ved Langeland (5906); Lb: ved Bøjgden (2154); Bra: ved Stevns Klint (M.B.H.). ' Cer. strictum foreltomnicr siliUert iliUc i Fnrvaiulet ()iiillter, som baade kan voxe op og ned, mest dog opad og undertiden kun i ringe Grad nedad. I den helt bark- klædte Del naar Barken sædvanlig ikke nogen stærk Udvikling; den er ret stor- cellet, bestaar af ca. 2 Lag og minder ved sin Modsætning mellem Axecelledel og Diaphragmedel om den tilsvarende hos Cer. Rosenvingii. Haar er almindelige; Farven lyst rødlig med blaalig Tone. Tetrasporangierne sidde i 1-2 Kredse, indsænkede. Cystocarpierne ere omgivne af 3—4 Svøbgrene og er insererede paa Siden af de øvre Gaffelgrene; sjældne ligesom Antheridierne, som jeg kun har bemærket en Gang. Epipliytisk paa lavere og dybere Vand (indtil c. 20 Meter?), efter Kylin i Littoralregionens nederste Del og i Subliltoralregionen, i P'arvandet ved Frederiks- havn fra l'/'2 til 11 Meters Dybde. Væsentlig en Soramerform. Sandsynligvis vil unge eller svagt barkede hidivider af denne Art kunne forvexles med Cer. cortica- tulum Kylin. Funden i nordlige Kattegat, Samsøpartiet, Storebælt og Lillebælt paa følgende Lokaliteter, nemlig Kn: Nordre Bønner ((5153) (6168); Frederikshavn (C.M.Poulsen) og Farvandet der omkring Juni— Juli 1908; Trindelen (2795) (2767); Sa: Lillegrund ved Fyns- hoved (1566); Klepperne ved Samsø (2895); Lb: Fænø Sund (400); B\v: Gulstav ved Langeland (3687). Anmærkning. Cer. rubriforme Kylin (op. c. pag. 183). I Farvandet omkring Frederikshavn (Kn) forekommer Cer. Areschougii meget hyppigt og synes der at variere en hel Del, hvad Barkens Udvikling angaar. Jeg fandt (Juni — Juli 1908), at enkelte Individer kunde være ganske rubrumagtige med en Bark som den, Kylin har beskrevet for Cer. rubriforme. Disse Individers For- bindelse med Cer. Areschougii var utvivlsom ; paa den anden Side kom der ogsaa i det habituelle noget frem, der kunde minde om Cer. rubriforme. Uden at benægte Exislensen af Cer. rubriforme som Art, skal jeg kun pege paa Muligheden af Op- fattelsen af denne Art som en Variant af Cer. Areschougii. Ceramium fruticulosum Kütz. J. G. Agardh emend. Tab. IV, Fig. 1—4. Syn.: Hormoceras fruticulosum Kütz. Sp. alg. pag. 676. Kiitzing: Tab. phyc. Vol. XII, Tab. 73. Agardh: Analecta algologica Cont. II: De typis Ceramiornm, pag. 31. I sin Afhandling: De typis Ceramiornm anvender Agardh dette Artsnavn for de europæiske Former af Ceramium Slægten, som havde i særlig Grad opadvoxende Bælter: cellulas igitur excurrentes, quibus adproximari videntur genicula proxima, a margine superiore geniculorum præcipue provenire mihi adparuit. Med hvilken Bet han henfører disse Former under Kiitzings Navn, skal jeg ikke her komme nærmere ind paa ; Bælterne i Kiitzings to Figurer (f& g) er ikke særlig opadvoxende, den tredje Figur (e), der visei- Ariens Habitus, stemmer derimod ganske godl mod del 33 71 Udseende, som flere Former af denne Gruppe have. Mulig vil det vise sig, al Navnet fruticulosum bør ændres; hvilket Navn man nu end vil tage, ændrer det dog ikke for mig Sagens Realitet: kun een Art for de af mig her omtalte Former, ikke flere Arter, som Kylin har gjort sig til Talsmand for. Individerne af forskellig Størrelse, ofte meget store, indtil c. 20 Ctm. i Diameter. Paa den ene Side nærmer de sig Cer. Aresclwugii, paa den anden Side Cer. riibnuv. Ligesom i foregaaende Tilfælde med Hensyn til Cer. Rosenuingii og arborescens er Overgangstilfældene til Cer. rubrum vanskelige at behandle. Forgreningen er hos forma penicillata yderst karakteristisk med tydelige Hovedstammer og toradede Grene; iøvrigt er den ikke særlig ejendommelig. Sekundære Skud er tilstede i højere eller ringere Grad. Grenspidserne ind- krummede eller rette. Barken er meget forskelligt udviklet. Snart finde vi lutter frie Bælter, snart en næsten sammenhængende Bark, snart en Forening af bægge Dele med stadig jævn Overgang fra den ene Type til den anden, saaledes at al Begrænsning vilde være yderst vilkaarlig. De frie Bælter er ofte meget høje, over dobbelt saa hoje som brede — med alle Gruppens Karakterer i Retning af Væxt. Barken er meget kraftigere udviklet end hos Cer. Areschougii, ofte med mange Lag af rubrum-agl\g Karakter o: ofte stærkt smaatcellet i det yderste Lag. Haar almindelige. Farven er mere eller mindre mørkt brun eller rustrød. Tetrasporangier i een — flere Rækker, indsænkede, ofte paa særlige, sekundære Grene og mod Spidsen. Cystokarpier side- eller endestillede uden særligt bemær- kelsesværdigt, undertiden paa smaa sekundære Skud, sjældent forekommende ligesom Antheridierne. Forekommer vistnok hele Aaret igennem paa lavere og dybere Vand, hyppigst paa lavere Vand i den littorale Zone dels som Epiphyt dels paa fast Substrat (Bolværker etc.). 1. Cer. fruticulosum forma rescissa (Kylin). Tab. IV, Fig. 2. Syn. Ceramium rescissum Kylin I. c. pag. 182, Tab. 7, Fig. 4. Forgreningen er enten almindelig dikotom eller der finder, som det er typisk for de ægte Cer. rubrum Former, en Udvikling af Hovedstammer Sted. Barken enten alene ordnet i Bælter eller der forekommer paa en større eller mindre Strækning sammenhængende Bark. og det er da ikke alene mod Basis, at denne kan findes; undertiden er de øvre Dele helt rubrum-aglige. De helt frie Bælter sædvanlig høje (indtil c. 500 /i) med tydelig, skarpt afskaaren nedre Rand. Barken mere eller mindre tæt af et rubrum-agtigt Udseende. Undertiden kan de mindre barkklædte Individer have et vist Habitus af Cer. diaphanum, med hvilken Art Former af Cer. fruliculosum vistnok mange Gange ere blevne forvexlede. Hertil hører Individer tagne i Kn: Udfor Frederikshavn; i Frederikshavn Havn, i Sæby Havn, samt i Sk: ved Bragerne og paa Hirshals Mole; i Frederikshavns Havn og Farvandel derom- kring kan Formen betegnes som almindelig. [Overgang til „forma penicillata danner 1). K. 1). \i.lensU. SeKk. S1.1- . 7, li;i-l., 7. H. V.2 IH. E. Pktkiisen] Ta», i 1. Cer. lenuissinuun. (Sk.: ■>. 1. Or. dinphnnun. forma lypica. iHm, Sai; :i. Cer. rtU.phaiium forma modificata, (Sm); .5. Cer. diaphamim forma modüuuta (v<,isine de forma radiculosai, (Su);.?-,«. Cer. .sirictum forma stricto-lenuissima, (Sb); /. Cer. striclum forma vera. (lîb). (1, 2, 3, 4 et .5: échelle V»; 6 el 7: éch. %). D. K. D.ViuKNSK.Sici.sK. Sku., nai inv. oc, math. An) , 7. R. V.'i (H. E.PktkhsenJ Tab. 11 h. H' Ä^^ v^^ f 1. Cer. slricUiiii lurniu vt-ni n'-pipliytc sur Cer. ruliium), (Sb): 2. Cer. vertébrale, iBbl; ;i. Cer. (liaiibiiiuun forma slrictoides (a). iSul; 4. Cer. diaphanum forma radiculosa, (lib); .5. Cer. Ro-senvingii forma tenuis, (Li); G. Cer. Rosenvingii forma intermedia, iKni; 7. Cer. ISosenvingii forma transgrediens, (Sl>). i2. S et 4: éch. =/«; 1 et 5: éch. -/s; 6 et 7: écli. ' ii. n. K. D.VlDKNSK. SiM.SK. S|2). (2. 4. 5 el (i: éoh. ^'ja; 3: éeh. -a; 1: éch. ^s). D. K. D.ViDK.NSK. Ski.sk. Sku., natuhv. og math.Afu., 7.R. V. 2 [H.li I'i;ti:iisi;n| Tab. V 1. Cer. rubrum lorma proliféra (une forme irrégulaire voisine de forma secundata), (Sl<); 2. Cer. rubriuii liinna irret;ulari.s, (Sa); 3. Cer. rubrum forma modificata (voisine de forma subtypica æsliva), (Kn); 4. Cer. rubrum tormn irrcRularis (voisine de forma subtypica æstiva), (IJ). (1 et 3: éch. =/a; 2 el 4: écli. ';s). D. K. D \'idex.sk.Si;i.sk.Sku.. natihv. og math.Ai-d., 7. H. \'.2 [H. li. l'EriutsEx] Tau. vi 1. Cer. rubrum forma irregularis (individu croissant sur le fond). (Su); 2. Cer. rubrum forma sublypica a-sliva (voisine de forma irregularis). Su): 3. Cer. rubrum forma radians, (Sf): 4. Cer. rubrum forma irregularis individu épiplivle sur l'ucus). (Su). 1 et 2: éch. ïj; 3 et 4: éch. 'a). D. K. D.ViDiiNSK. Sf.i-sk.Skh., nati iiv. .... math. Ai i>., 7. R. V. 2 [H. E. Pi;tkusi;n] Tab. VII 1. Cer. rubrum Ibrina Imltica, (Bb); 2. Cer. rubrum forma proliféra (voisine de forma secumiala). (Horilö. îles Kéroê, F. Rör- gesen): 3. Cer. nibruni l<.rm:i irregularis. (Ke); 4. Cer. rubrum forma divaricata, (Li); 5. Cer. rubrum forma baltica, (Bbl. (1; éch. 5/c; 2, 3 et 4: éch. «/a; 5: éch. Vs.) THE DANISH EXPEDITION TO SIAM 1899-1900 I). Kgl. Danske Vidensk. Selsk. Skrifter. 7. Kække, naturvidensk. og matheni. Afd. V. 3 IV. Marine Lamellibranchiata by Herman Lynge With 5 plates and a map f>t^' ^ V 8 København Bianco Lu nos liogt rv k keri 1909 1 he present work upon Ihe Lamellihranchiala collecled by the Danish Ex- pedition to Siam I'orms the first part of a description of all the testaceous Mollusca of the Gulf of Siam, which I hope to publish gradually, the description being based upon the excellent collections made by Dr. Th. Mortensen during the Danish Expedition 1899-1900. I have thought it right to include in the present work all the species which have hitherto been recorded from the Gulf of Siam, even although not collected by the Danish Expedition to Siam. I wish heartily to thank Mr. G. M. R. Levinsen of the Zoological Museum of the University of Copenhagen for freely placing the collections of the Museum at my disposal; also 1 am much indebted to my friend at the Zoological Museum, Mr. Ad. S. Jensen, for his unfailing help in searching out material for comparison. Unfortunately, our museum in Copenhagen, although excellent in other respects, is not rich in Asiatic Mollusca which could have been of use to me for the sake of comparison. 1 was therefore verj' much pleased, when, during my sojourn in London (which 1 visited before finishing my work), 1 was able to avail myself of the much richer collections in the British Museum of Natural History, owing to the ready courtesy and kindness of Mr. Edgar Smith, to whom I tender my heartiest thanks. I am also indebted to Messrs. Ph. Dautzenberg, Paris, to the late Professor En. v. Martens of Berlin, and to J. Cosmo Melvill Esq. of Shrews- bury for information and intelligence. To Dr. Th. Mortensen, who from the beginning has taken a great interest in my work, and has always been ready with advice and information, I wish to offer my hearty thanks, and also to express my appreciation of the way in which, during the Expedition and often under very difficult circumstances, he has got to- gether such excellent collections, which have in so many ways enriched zoological science with valuable material. Copenhagen, December iyU8. Herm. Lynge. 13* Introduction. Wur knowledge of the marine Lamellibranchiala of the Gulf of Siam was for a long time very limited. Thus, when Professor Ed. v. Martens, in 1860, puhlislicd his paper "On the Mollusca of Siam" in the "Proceedings of the Zool. Society of London," he mentioned in it only 7 species of marine Lamellibrnnchiata. Nor was our knowledge of the fauna enlarged until L. Morlet described Mr. Pavie's collections in the "Journal de Conchyliologie," 1889; bul in 1891, when Paul Fischer published his "Catalogue el distribution géograph. d. Mollusques terrestres, fluvialiles el marins d'une partie de l'Indo Chine" ' lie was able lo record 72 species of marine Lamellibranchiata from the Gulf of Siam, and this number has been in- creased to 85 species by Pavie's new collections, which Crosse & Fischer, in 1892, described in the "Journal de Conchyliologie." By Dr. Th. Mortensen's thorough and excellent dredgings and collections from the eastern part of the Gulf of Siam during the years 1899 — 1900, the number of known species of Lamellibranchiala from that place has now been increased to 379 species. But the fauna is without doubt slill far from exhausted by this last addition, because the Danish Expedition dredged only in the northern and eastern parts of the gulf, and only down to a depth of about 35 fathoms. The Mollusc fauna in the western part and also in the deeper parts in the middle of the gulf is still unknown. Il is true that the "Skeat-Expedi- lion" has made collections on the Malacca side of the gulf, but the Mollusca of these collections have not yet been worked out. Thus, as it is only the littoral fauna of a part of the gulf which is known, it must be understood that the present list is only the beginning of a complete list of the species occurring in the gulf. Though it may be supposed that the littoral fauna of the northern and eastern parts of the gulf is now almost completely known, yet it is probable Ihal the fauna of the western side of the Gulf of Siam is richer, and contains many species which have not hitherto been taken on the eastern side. This is owing to the fact that the water on the Malacca side is much purer and fresher than in the eastern part, where the outlets of the numerous rivers make the sea-water foul and muddy and also less saline.^ ' Bulletin Soc. Hist. Nat. d'Autun. IV, 1891, pp. 87-276. - Cf. Th. MoRTiiNSEN, "The Danish E.\pedition to Siam, 1899— 190(1. Results of tlie zoological Collections." Kgl. Danske Vidensk. Selsk. Skrifter, 6. R. Naturv, og matliem. Afd. XII, 2, 1902, pp. 155—57. 5 101 On comparing the LameUihranchiala hitherto descrihed from the Gulf of Siani with those of other more thoroughly investigated parts of the Asiatic waters, we lind, according to Melvill & Standen, that 426 species (among which are many deep water forms) are recorded from the Persian Gulf, the Gulf of Oman, and the Arabian Sea. Besides the fact that this fauna has many species in common with that of the Gulf of Siam, the two faunas correspond in many points with each other in regard to character. Unfortunately, J. G. Hidalgo's work on the Lamellibranchiata of the Philippines is not yet finished, so no definite number of species can be recorded from that place. In Casto de Elera's uncritical -'Catàlogo sistemàt. de toda la Fauna de Filipinas,' III, 1896, more than 800 Lamellibranchiata are recorded from the Philippines. From Japan, Pilsbry gives in 1895 over 500 species in his "Cata- logue of the Marine Mollusks of Japan," and he has afterwards added several to these. The new species and varieties which will be described in the following pages are; — Area (Barbalia) Siaiuensis. — (Anadara) Mortenseni. — (Scapharca) clichotoina Desh. var graiiosa. Carditella pusilla. — pulcbella. Liicina (Phacoides) Dalli. — [Phacoides) pulchella. Kellija lineata. — rosea. — vilrina. — elongala. — lilium. Montaciita costata. — nenusta. — (Tellimiia) imriabilis. — (Tellimya) riidis. Tellina {Arcopagia:') Smitbi. — (Merisca) Martensi. — [Moerella) Berghi. — (Macoma) temiiscalpta. Circe Melrilli. Chione [Timocleu) Siamensis. Hemicardium {Fragiim) fragum L. var. carinata. Corbula lineata. — arcaeformis. — (?) mirabilis. Sphenia quadrangularis. 102 6 If we dra^v any conclusions concerning the character of the whole fauna, we may confidently say, even if convinced that it is but imperfectly known, that it belongs entirely to the Indo-Pacific Fauna. I do not think forms occur which are peculiar to the Gulf of Siam ; if so, they may possibly be some of the species of the Mangrove fauna (e. g. Lucina Dalli m.), but I do not believe even these to be peculiar to the Gulf of Siam, they can without doubt be found also in other similar localities in Indian waters. The classification is partly that proposed by Professor P. Pelseneer in 1894 in his "Introduction à l'étude d. mollusques"', vv'hich is based on the study of the comparative anatomy of the more minute details of the gills; not that I consider it to be quite satisfactory, but, unfortunately, that is true of all other older systems 0Î Ihe Lamellibrcinchiata. I have ventured upon some alterations in his system; for instance, I have not reckoned Psammobia to Mgacea, as he does, but placed it under Tellinacea, to which it belongs more closely, judging from other systematic characters. I have retained Pinna under Pteriidae, to which it most naturally be- longs, and not in the neighbourhood of Ostrea and Lima where Pelseneer would have it. To employ the structure of the gills exclusively as the basis of a classifica- tory system^, without taking other features into consideration, especially the struc- ture of the hinge, is in my opinion absolutely wiong in the case of the Lamelli- branchiata. ' And afterwards revised in liis "A Treatise on Zoology, ed. by E. Rav Lankestkk, V. Mollusca by 1'. Pelskneeh, Loudon, 1906." ^ Cf. E. L. Rice, "Die systemat. Verwertbarkeit d. Kiemen bei d. Lamellibrancliiaten." Jenaische Zeitschrift f. Naturwissenschaft, 31. Hd , 1898, p. 29. Order Protobranchiata. Farn. Nuculidae. Nucula Cumingi, Hinds. Nucula Ciimingii, Hinds, Proc. Zool. Soc. London, XI, 1843, p. 97. — — — Zoology of the Voyage of -'Sulphur." Mollusca by Hinds, 184.'), p. 62, pi. 18, fig. 1. — — — Hanley, Monograph of the fani. Nuculidæ. (Sowerby, Thesaurus Conchylio- rum III.) p. 157, pi. IV, fig. 117. — — — Reeve, Conchol. icon., XVIII, Nucula, Sp. 5. The Gulf of Rayong and Cape Liant. Common around Koh Kul and Koh Kalidat, 4—30 fathoms, sand, mud and shells. ' Long. 4 — 12 mm. Distribution: — Singapore, Strait of Malacca, Philippines, New Guinea, Strait of Macassar. Nucula Layardi, A. Ad. Nucula Layardii, A.Adams, Proc. Zool. Soc. London, XXIV, 1856, p. 51. — Layardi, — Hanley, Monogr. of the fani. Nuculidæ (Sowerby, Thesaurus Conchy!., III.) p. 160, pi. V, fig. 153. — — — Reeve, Conchol. icon. XVIII. Nucula. Sp. 36. — - — Edg. Smith, Ann. and Magaz. Nat. Hist., 7. .Ser., XVIII, 1906, p. 252. West of Koh Chuen, soft clay and mud. (^2).^ The Sound of Koh Chang, 3—5 fathoms, soft clay (many specimens). The coast of Lern Ngob, low tide ('(3). Long. 4 — 10 mm. Distribution:— Ceylon, Bombay, Karachi, Mekran Coast, Gulf of Oman, Persian Gulf. Reeve (loc. cit.) is correct in saying that the present species is much more nearly allied to N. Cumingi than to N. convexa (as stated by A. Adams). The out- line of N. Layardi corresponds almost completely with that of N. Cumingi. The number of the hinge-teeth ("six in front and nineteen behind") stated by Edg. Smith (loc. cit.) to occur in his "single shell", which measured 15 mm. in length, is not always constant, more or fewer teeth frequently occurring. Undoubtedly the age, size and development of the individual also have a share in regard to this feature. ' In the list of localities "sand," "mud", "stones," etc. stand for "sandy bottom," "muddy bot- tom." "stony bottom," etc. ' Tlic numlier in parenthesis indicate throughout the number of specimens collected. 104 Yoldia tenella, Hinds. Nucuhi tenella, Hinds, Proc. Zool. London, XI, 1843, p. 99. — — — Hanley, Kec. bivalve shells, p. 370, pi. 19, fig. 47. Leda _ _ _ Monogr. of the fam. Nticiilidw (Soweuby, Thesaurus Conchyl., 111) p. 137, No. 56, pi. 1, lig. 15. Yoldia — — Reeve, Conchol. icon., XVIII, Yoldia, Sp. 4. Koh Chuen, 10—15 fathoms ('/a). West of Koh Chuen, soft clay and mud (1 + Vs). East of Koh Mak, 20 fathoms, mud {'i-j). W. of Koh Kul, 3(1 fatlioms, sand and mud (-'/j). N. of Koh Kut, 10 fathoms, mud ('/a). Long. 4 — 11 mm. Distribution:— Singapore, Gulf of Oman (Melvili. ä Standen). Yoldia serotina, Hinds. Nucnla serutina, Hinds, Proc. Zool. Soc. London, XI, 1843, p. 99. Leda — — Sdwebby, Thesaurus Conehyliorum, III, 18G6. Monogr. of the fam. Nncitlida' by Hanley, p. 136, No. 54, pi. 1, figs. 19—21. Yoldia — A. Adams, Reeve, Conchol. icon., XVIII, Yoldia, Sp. 5. Leda lepida, - Proc. Zool. Soc. London, XXIV, 1850, p. 49. South of Koh Kut, 17—20 fathoms, mud (Ma). Long. 4 mm. Distribution: — Singapore, Gulf of Oman (Melvill & Standen). — PhiH|)- P nes, Borneo. Nuculana Belcheri, Hinds. (PI. 1, Figs. 18-19). Niicula Belcheri, Hinds, Proc. Zool. Soc. London, XI, 1843, p 98. — — — Zoology of the voyage of "Sulphur." Mollusca by Hind.s. 1845, p. 63, pi. 18, fig. 11. Leda — — Hanley, Monogr. of the fam. Niicu/i'dœ (Sowhiikv, Tlicsaurus Conchyl., Ill), p, 116, pi. 2, fig. 53. Lœda — — Reeve, Conchol. icon., XVIII, Lœda, Sp. 23. Nuculana — — Smith, Proceed. Malacolog. Soc. London, V, 19(13, p :f95, No. 346. The Sound of Koh Chang, 5 fathoms, soft clay. ('/a). Long. 10 mm. Distribution:— Agulha Bank, Cape of Good Hope (Belcher), oil" Cape Colony and Natal, 34—440 fathoms (Edg. Smith). ' The single valve obtained from the Gulf of Siain is not full-grown, therefore, as may be seen in PI. 1, F'ig. 19, the characteristic central keel, which extends from the ventral side towards the umbo, is absent at the posterior end: this agrees entirely with the opinion expressed by Hanley (loc. cit., p. 117) "As the central keel does not extend to the umboes, it is probably wholly absent in Ihe fry." ' On Siiutli African Marine Mollusca. (Annals of llio Natal Government Museum. Vol. 1, p 1. 1906). 105 Nuculana puellata, Hinds. Nticula piiellala, Hinds, Proc. Zool. Soc. London, XI, 184.'!, p. 100. — — — Zoology of the voyage of "Sulphur." Mollusca by Hinds, 1845, p. 64, pi. 18, fig. 18. /_,.,/„ — — Hanlet, Monogr. of the fam Niiculidæ (Sowekby, Thesaurus Conchyl., Ill), p. 127, pi. 3, fig. 94. /.(£(/(( — — Reeve, Conchol. icon., XVIII, Lœda. Sp. 34. Koh Chuen, 10—15 fathoms (common). W. of Koh Chuen, soft clay and mud (very common). S. of Koh Samit, 20 fathoms, mud (Vs). Sound of Koh Chang, 3—5 fathoms, soft clay (common). West coast of Koh Chang, 10 fathoms, mud ('•-). S. of Koh Bidang, 9 fathoms, mud (common). S. of Koh Kahdat, 8—10 fathoms, mud ('/a). Between Koh Kahdat and Koh Kut, 6 fathoms, clay mixed with sand ('";:!). W. of Koh Kut, 15 fathoms, mud {^k). N. of Koh Kong, 8 fathoms, mud (2). W. of Koh Kong, 10—15 fathoms (^li). Long. 3 — 8 mm. Distribution: — Malacca, NE. coast of New Guinea (Brazier). There is great variability in the length of the rostrum, and in some specimens it may be much longer than is shown in the figures given by Hinds and Hanlev. Reeve's figure is very misleading, for the sculpture — which in reality consists of an exceedingly pretty, fine, regularly concentric striation — in his figure is highly irregular and undulating. Nuculana mauritiana, Sow. Snciila MaiiritiaiKi, G. B. Sowerbv jun., Conchological Illustrations, 1833, Nuciila, p. 4, No. 22, fig. 17. — — — Hanlev, Catal. of rec. biv. shells, p. 170. pi. 19, fig. 46. Lœda — — Reeve, Conchol. icon., XVIII, Lœda, Sp. 33. Leda — — Sowerbv, Thesaur. Conchyl., Hi (Hanlev, Monogr. of tlic fam. Sucii- Udæ\ p. 126, No. 38, fig. 99. Between Koh Lan and Koh Kong, common, taken in great number in 6—30 fathoms, mud, clay mixed with sand, shells. Long. 2 12 mm. Distribution: — Mergui Archipel., Ceylon, Bombay, Mekran Coast, Mauritius. — China. Many of the specimens from the Gulf of Siam bear a close resemblance to Nuculana nasuta, Sow. Nuculana retusa, Hinds. Niicula retusa. Hinds, Proc. Zool. Soc. London, XI, 1843, p. 99. — - Zoology of the voyage of "Sulphur." Mollusca by Hinds, 1845, p. 63, pi. 18, fig. 9. Leda ll'urtlandia} retusa, Hinds, Hani.ev, Monograpli of the fam. Nuculidæ (Sowekby, Thesaurus Concliyl. Ill), p. 146, No. 71, pi. 2, figs. 28—29. Yoldiii retusa. Hinds, H. & A. Adams, Genera of rec. Moll., II, 1858, p. 548. - Reeve, Conchol. icon, XVIII, YoMiü, Sp. 21. DK 1). Vhleiisk SelbLi, Slii-, 7 RicUke. nriliiiv iilensk. ii|,i ni:illieni Afil. V. :i. 14 106 10 East of Koh Chuen, 9 fathoms (1). Long. 1-75 mm. Distribution: — Strait of Malacca. — Philippines. Order Filibranchiata. Fam. Anomiidae. Anomia sol, Reeve. (PI. 1, Figs. 1—2). Anomia sol, Reeve, Coiicliol. icon., vol. XI, Anomia, 1859, Sp. 4. — — CnossE et Fischer, Journ. dc Conchyl., vol. 37, 1889, p. 290. Coast of Lem Ngob (3). Gulf of Klong Salakpet (3). W. of Koh Kut, 30 fathoms, sand and mud. On stones and shells (for instance on Perna Ciimingi, Reeve). Long. 57 mm., alt. 51 mm. (sp. max.). Long. 8 mm., alt. 8 mm. (sp. min.). Distribution:— Kurachee (Indus.). — Annam. The upper valve, in the specimens from the Gulf of Siam, has a peculiar wrinkled (in the younger specimens nodose) appearance; the interior has a nacreous lustre. A. plenilunium, Reeve (from Borneo, Mergui Isis, and several other places) is, no doubt, only A. sol. Reeve, although Reeve states that "The under valve is tumidly raised about the orifice, with flexuous lines diverging around;" this is undoubtedly only an individual character. Anomia amabaeus, Gray. tl'l. 1, Figs. 3-4). Anomia amabwus, Gray, Proc. Zool. Soc. London, XVII, 1849, p. 115. — — — Reeve, Conchol. icon., XI, Anomia, Sp. 7. — drgas, — Proc. Zool. Soc. London, XVll, 1849, p. 115. — — — Reeve, Conchol. icon., XI, Anomia, Sp. 24. Koh Lan, 30 fathoms, mud (1). Between Koh Rin and Cliff Rock, 15 fathoms (1). The northern side of Koh Mesan, 10 — 15 fathoms, stones (3). S. of Koh Chuen, 30 fathoms, shells (2). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (3). Long. 18 mm., alt. 21 mm. (sp. max.). Long. 8 mm., alt. 8 mm. (sp. min.). Distribution: — Singapore (A. drgns), Philippines {A. amabaeus). 11 107 Judging I'roin the material at hand, and after having examined tlie original specimens in the British Museum, I cannot see that there is any dilTerence between Gray's two species A. amahaeus and A. dryas (some specimens from Koh Mesan agree almost completely with Reeve's A. dryas). The hinge in the species we are here considering presents a peculiar feature, which may be seen in PI. 1, Fig. 4; there is, in the upper valve a keel which extends internally from the point of attachment of the ligament to the dorsal margin of the valve, a similar case I have neither met with, nor seen described, in any other species of Anomin. The umbones are situated at some distance from the margin of the valves. Anomia (Aenigma) aenigmatica, Ch. Tdlina aenigmatica, Chemnitz, Conchyl. Cabin., XI, 1795. p. 211, pi. 199, figs. 1949—50. Anomia — — Anton, Archiv f. Naturgesch., Ill .lalirg. 1 Bd., 1837, p. 285, No. 13. — œnigmalica, — Reeve, Couchol. icon., XI, 1859, Anomia, Sp. 37. — — — Gray, Proc. Zool. Soc. London, XVII, 1849, p. 118. — _ _ _ Catal. Biv. Moll. Brit. Mus., I, 1850, p. 20. — — — MoRLET, Journ. de Conchyl., vol. 37, 1889, p. 160. Aenigma — — G. C. Bourne, Quart. Journ. of Microscop. Science, No. 202. 1907. pp. 253—95, pi. 15—17. — rosenm, Ghay, Mautini u. Chemnitz, Conchyl. Cabin., VII, 1. ."^btli , p. 02, pi. 7, figs. 1 — 7. — rcticniatum, Koch, Martini u. Chemnitz, Concliyl. Cabin., VII, 1. Abtli., p. 62, pi. 7, fig. 8. — convexam, _ _ . — _ — — p. 63, pi. 7, figs. 9 — 12. — corruijatum, — — - — — — — p. 63, pi. 7, figs. 13 — 15. "Palmiers d'eau à Kanipot (o: Kampot) Golfe de Slam" (L. Morlet). Distribution: — Singapore, Delta of Irawady (Pegu, Burma), Bombay, Karachi, Persian Gulf. — Philippines, Borneo. The Danish Expedition to Siam collected no specimens of this species. Placuna placenta, L. Anomia ])laccnia, Linné, Systema Naturae, ed. X, 1758, p. 703, No. 205, ed. XII, p. 1154, No. 241. Mus. Ludov. Ulricæ, 1764, p. 536, No. 126. Placuna — — Lamarck, Hist. nat. d. anira. s. vert., VI, 1 p. 1819, p. 224, No. 3, éd. 2, VII, p. 270, No. 3. — — — Encyclop. method., pi. 173. — — — Martini u. Chemnitz, Concliyl. Cabin., VII, 1. Abth., p. 66, pi. 5, fig. 3. — — — Reeve, Conchol. icon., XVIII, Placuna, Sp. 3. — — — P. Fischer, Catalogue d. Moll, de I'lndo-Chine, p. 208. — — — HoRNELL, Rep. Ceylon Mar. Biolog. Laboratory, I, p. 2. 1906, p. 41. Placenta urbicularis, Binzius, Diss. sist. nova testaceorum genera. Lund, 1788, p. 15. — — — Melvili, and Standen, Proc. Zool. Soc. London, 1906, p. 793. Off Koh Kam, 10 fathoms, gravel ('/:!). S. of Koh Samit, 20 fathoms, mud (^/a). W. of Koh Chang, 20 fathoms, mud (1). Sound of Koh Chang, 3 — 5 fathoms, soft clay (many specimens). Coast of Lem Ngob (3). S. of Koh Kut, 17 — 20 fathoms, mud (2). N. of Koh Kong, 8 fathoms, mud (4). "Les grèves du golfe de Siam" (Morlet). 14' 108 12 Long, f)— 85 mm. Distribution: - Singapore, Mergui Archip., Andamans, Tranqiiebar, Ceylon, Panjim and Goa, Bombay, Karachi, Persian Gulf, Aden. — Annam, Poulo-Condor, Philippines, China, Japan, North, East and West Australia. PI. auriculala, Yoldi ^ from the Red Sea is only a form of PI. placenta L. which anteriorly and posteriorly is flattened in an ear-like manner above the dorsal margin. Such forms also occur among the specimens from the Gulf of Siam. A. WiLLEY- (loc. cit. p. 37, Fig. 1) mentions and figures specimens of PI. placenta from Ceylon with such ear-like lobes occurring on either side of tlie hinge-line, especially in young individuals. Placuna papyracea, Lam. Eptiippium parviim papyraccum Anglicanam scu Polonicum, Chemnitz, Conchyl. Cabin., VIII, 1785, p. 114, pi. 7). Koh Kahdat, 1 fathom, sand (1). Long. 12—33 mm. Distribution: — Singapore (The Danish Expedit, to Siam, 2 specimens, 2 — 3 fathoms, coral-reef), Mergui Isis., Nicobar Isis., Madras, Gulf of Manaar, Red Sea, Seychelles, Madagascar, Mascarenes, Querimba Isis. — Poulo-Condor, Cochin China, Philippines, Menlawei Isis., Celebes, Sulu Isis., Java, Small Sunda Isis., Moluccas, Aru Isl., Sorong, Torres Strait, North, East and West Australia, Salomo Isis., Viti Isis., Tonga Isis., Lifu Isl., New Caledonia, New Zealand. Lamy (loc. cit. p. 53) considers A. cruciata, Philippi and A. Rodatzi, Dunker (from Zanzibar) to be synonymous with A. fusca, Brug. Area (Barbatia) complanata, Ch. (PI. 1, Figs. 5— 10). Area complanata, Chemnitz. Concliyl. Cabin., VII, 1784, p. 198, pi. 55, figs. 544- 45. L. MoRLET, .lourn. de Conchyl., vol.37, 1889. p. 162. - (Barbatia) complanata, Chemnitz, P.Fischer, Catal. d. Moll, de I'lndo-Chine, p. 215. Byssoarca decunsata, Sowerbv, Proc. Zool. Soc. London, vol.1, 1833, p. 18. Area — — Reeve, Conchol. icon.. II. Area, Sp. 81. ' The ,I(nirn:il of the Linnc.in Soc, vol. XXI, 1887, p. 207. 112 16 Area (Barbatia) decnssata, Sowebby, Martini u. Chemnitz, Conchyl. Cabin, VIII, 2 Abtli.. ]). 144, pi. 37, figs. 2—5. — — — — E. Lamy, Bull, du Mus. d'Hist. Nat. Paris, 1904, p. 273. — Lw. cit. 1906, p. 317, No. 78. Byssoarca uelata, Sowerby, Proc. Zool. Soc. London, vol. I, 1833, p. 18. Area — — Reeve, Conchol. icon., II, Area, Sp. 79. Barbatia — — var., Dunkek, Novitates conchologicae, p. 124, pi. 41. Area (Barbatia) velata, Sowebby, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 207, pi. 49, figs. 2 -3. The north side of Koh Mesan, 10 — 15 fathoms, stones (1). Koh Chick, rocky coast (3). North end of Koh Chang, 1 fathom, old coral blocks (38). The same locality, 12 fathoms, old coral blocks (4). West coast of Koh Chang, 10 fathoms, mud (5). Koh Sarlak (2). Lem Ngob, on piles of bridge, very low tide (2). Koh Lom (3). Strand of Koh Kahdat (1). Koh Mak, sand coast (1 + •'/.,) "Sinum Siamensem habitare dicitur" (Barbatia uelata, Sow. var.. Dunker). Islands in the Gulf of Siam (A. complanata Ch., L. Morlet, loc. cit.). Long. 8—55 mm. Distribution:— Singapore,' Salanga, Mergui Archipel, Nicobar Isis., Madras, Ceylon, Persian Gulf, Gulf of Aden, Red Sea, Gulf of Suez and Akaba, Seychelles, Madagascar, Mascarenes. — Poulo Condor, China, Japan, Philippines, Celebes, Torres Strait, New Caledonia, Viti Isis., Funafuti (EUice Isl.), Paumotu Isl., Society Isis., New Zealand, Galapagos Isis. (San Thome in the Gulf of Guinea, Hoyle?). On the basis of the material at hand, I have united Area decussata, Sow. with A. velata, Sow. into one species, as it is not possible to keep these forms distinct, A. decussata merging by easy stages into A. velata, while the specific charac- ters which have been pointed out, are not constant. In PI. 1, Figs. 5—10 I have figured several forms which show this transition better than it could be shown by any description. It was undoubtedly owing only to the lack of a larger quantity of material that Sowerby established two species upon specimens taken in the same localities ("Lord Hood's and Chain Islands, Pacific Ocean, attached to shells. Cuming")."^ The literature gives indications of the great uncertainty which authors show in the determination of the highly variable ß«rZ>a/ia-forms; while a great number of species: — A. foliata, Forskå], '• revelata, Dsh., Petersi, Dkr. , sculptilis. Reeve and many others need to be known in more complete development- and varia- tion-series before their distinctness can be guaranteed. The reported occurrences of the West-Indian species Area Heblingi, Ch. (cundida, Gmel.) in Asiatic waters are without doubt due to erroneous determinations, and all the specimens in question should evidently be referred to A. complanata; nor is A. nivea, Ch. sufficiently defined as a species, and it needs revision.* Pagenstecher however, goes loo far,' when ' Taken by the Danish E.\pedition to Slam, four specimens, in 2 — 3 fathoms, coral-reef. "' In spite of Chemnitz's naming Guinea as the home of his species A. complanata, an undoubtedly incorrect statement, I have not hesitated in referring the forms we are here considering to tliat species. '■' v. Martens, Vorderasiat. Conchylien 1874, p. 103, pi. 9, fig. 58. ^ Ei>. Lamy, .lonrn, de Conchyl., vol. .'■)2, 19Ü4, p. 140. — Bullet, du Mus. d'Hist. Natur., 1904, p. 272. '"' Ueber die von B, Kossmann am Botheu Meere gesainm. Mollusken, Lpzg. 1877, p, 35. 17 113 he refers Area lactea var. eryihraea, Issel, from the Red Sea to A. deciissatct. Reeve (Sow.), as stated by A. H. Cooke,' it is in reality only a form of A. lactea L. — Lamy in his latest revision of the gen. Arca^ regards A. complanata, Ch., somewhat difVerently from the way in which I regard it here. He gives A. velata, Sow., as a variety of A. complanata, Ch. (which he names A. nivea, Ch.), and places A. decassata as a distinct species; but as Lamy's work was not published until I had finished my work upon the Area-group, I have not been able to consider it here. Area (Barbatia) lima, Reeve. Area lima, Reeve, Proc. Zool. Soc. Lond., XII, 1844, p. 125. — — — Conchol. icon., II. Sp. 101. — {Barbatia) lima. Reeve, Martini u. Chemn., Conchyl. Cabin., VIII, 2 Abtli., p. 115, pi. 30, figs. 5-6. — — — — Edg. a. Smith, Lamellibrancliiata of tlie Challenger Exped., p. 2G0. — — — — — Report on the zoolog, collect, made during the voyage of H. M. S. "Alert," p. 110. — — — — E. Lamy, Bull, du Mus. d'Hist. Nat. Paris, 1904, p. 273. — decussata, Sowekby var. lima, Reeve, Lamy, Journ. de Conchyl., vol.55, 1907, p. 65. Koh Kram, 6—10 and 30 fathoms (3). E. of Koh Chuen, 9—10 fathoms, shells (2). Koh Chuen, 10—15 fathoms (2). S. of Koh Chuen, 30 fathoms, shells (■'/a). OtT Koh Kam, 10 fathoms, gravel (1). Gulf of Rayong, sand, mud and shells (1). North and west coast of Koh Chang, 1 fathom, old coral blocks (12). Koh Kahdat, 1 fathom, sand (2). W. of Koh Kut, 30 fathoms, sand and mud ('/s). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (5). S. of Koh Kahdat, 8—10 fathoms, mud (2/2). Long. 3—45 mm. Distribution: — Singapore (low water, Sv. Gad), Madras, Gulf of Manaar, Laccadive and Maldive Archipel., Gulf of Aden, Red Sea (pleistocene). — Philip- pines, Torres Str., Port Molle, St. Vincent's Gulf, South Australia, South. Paumotu Isis. The following species may safely be reckoned as synonymous with Area lima, Reeve: — Barbatia oblonga, Dkr. ■' (non Anomalocardia oblonga, Phil, et Dkr.), Area granulata, Phi\.,^ from the Sandwich Islands, Barbatia (Acar) aeerœa, Melv. & Stand.'' Edg. a. Smith "^ slates that A. trapezina, Lam. ("as determined by Reeve"), is probably a form of A. lima. Reeve; how far trapezina, Lam., is on the whole a form of A. lima I am not at present prepared to say; that the whole ßarZ)ah'a-group — when, later, a larger quantity of material is at hand and further comparative in- vestigations have been carried out — will unquestionably be reduced in many respects, is practically certain. In many cases it is very difficult to determine young specimens of A. lima and to keep them distinct, as for example from A. complanata, ' Annals and Magazine of Nat. Hist., 5. ser., vol.18, 1880, p. 93. - Journ. de Conchyliologie, vol.55. 1907, p. 59. ■' Novitates Conchologicae, p. 107 and p. 85. ^ Abbild, und Beschreib, neuer od. wenig gekannt. Conchyl., Ill, p. 114 (22), pi. VI. lig. 3. ■ Journ. Linn. Soc. Zoology, vol. XXVII, p. 180, pi. 10, lig. 15. '■ Proc. Zool. Soc. London, 1891, p. 431. I). K, II, Viilfilsk. Selsk. Skr.. 7. Ha-kke, nalurviilensk. oj! niiithem. Al'il V. 3. 15 114 18 Ch. I cannot agree with Edg. Smith when he says ' that "The few ribs towards the middle being duplicate, as stated by Reeve, is an individual rather than a specific character;" in all the specimens from the Gulf of Siam the majority of the ribs in the middle towards the hinder extremity are duplicate. As mentioned in connec- tion with A. compktnata, Gh., I have unfortunately not been able to lake into full consideration Lamy's work on the genus Area, as my investigations upon this genus were ended when the work in question was published. Area (Barbatia) parva, Sow. Bgssoarca pari'a, Sovverby, Proc. Zool. Soc. London, 1833, p. 19. Area * — — Reeve, Conchol. icon., II, Area. Sp. 119. — (Barbatia) parva, Reeve, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Al)tli., p. 197, pi. 47. lig. 7. — — — SowERBY, Lamy, .lourn. de Conchyl., vol.55, 1907, p. 51. Barhalia attenuata, Dunker i. I. Museum Godeffroy. Catalog IV. 1869, p. 114 — Catalog V, 1874. p. 173. West coast of Koh Chang, 10 fathoms, mud (1). Koh Mak, sand coast ('/2). Long. 15 — 21 mm. Distribution: — Persian Gulf, Djibouti, Gulf of Suez, Madagascar. — Tahiti, Paumotu Isl., Ducie's Isl. Area (Barbatia) Siamensis, n. sp. {PI. 1, Figs. 16—17). This shell is rather thin and ventricose, oblong rectangular in outline, and the posterior half is swollen from the umbones obliquely downwards towards the posterior part of the ventral side. The valves are somewhat obliquely twisted, and the left valve projects, having its lower edge below that of the right valve. The anterior end is rounded and passes evenly into the ventral side; the posterior end, which is much higher, is rather straightly truncate and slopes obliquely downwards towards the ventral side, with which it makes a rounded angle; the ventral side is somewhat compressed in the middle. The surface of the valves is closely set with about 48 flattened, smooth, radiating ribs, which are provided with a longitudinal furrow towards the anterior end. The interstices between the ribs are narrower than the ribs. From the umbones and down to the middle of the ventral side there is a depression of the valves. The upper margin is straight and rises sharply towards the posterior end. The umbones are situated in the anterior third of the shell. The area is very narrow and long. The colour is white and the hinder margin of each valve is dark-coloured. The sur- face is covered by a thin, brown epidermis which in the interstices between the ribs is set with small scales or bristles. There are about 47 hinge-teeth. The interior of the valves is white, and the outer ribs project beyond the margin so that the latter becomes dentate. ' Report on the zoolog, collections made during tlie voyage of H. M. S. "Alert," p. 110. 19 115 Long. 24 mm., alt. 14 mm., crass. 10 mm. Between Koh Rin and CI i tV Rock, 15 fathoms ('/a). Koh Kiam, 3Ü fathoms (Vs). Gulf of Koh Chang, 3—5 fathoms, soft clay (^/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (-'/a). This characteristic species is nearest related to A. obliqiiata. Gray, and A. decussata, Lischke, but may easily be distinguished from these forms. Area (Fossularca) pectunculiformis, Dunk. Barbalia pectunculiformis. Dunker, Novitates conchologicae, 18()6, p. 88, pi. 28, figs. 4 — (i. Area (liurbatia pectunculiformis, Dunker, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abtli., p. 125, pi. 32, fig.s. 5— 6. — (Noetia) — — I.amy, Journ. de Conchyl., vol. 55, 1907, p. 300. W. of Koh Chuen, soft clay and mud ('^/a). S. of Koh Samit, 20 fathoms, mud (^/a). Gulf of Koh Chang, 5 fathoms, soft clay (^/j). Strand of Koh Kahdat (»Wa). S. of Koh Kahdat, 8—10 fathoms, mud {^h). Between Koh Kahdat and Koh Kut, 6 fathoms, clay mixed with sand (^^/s). S. of Koh Kut, 17—20 fathoms, mud ('/a). W. of Koh Kut, 15 fathoms, mud (^/a). W. of Koh Kong (1). Long. 3 — 10 mm. Distribution: — Karikal (Coromandel Coast, subfossil, Dautzenberg), Borneo (Dunker), Surabaja (Java, Ed. v. Martens). ' Ana olivacea, Reeve, is very closely related to this species. Can some of the recorded occurrences of A. lactea L. in Asiatic and Australian waters, be due to erroneous determination of A. pectunculiformis, Dunk.? Area (Fossularca) sculptilis, Reeve. Area sculptilis, Ri;i:vi;, Proc. Zool. Soc. I^ondon, 1844, p. 128. — Conchol. icon., 11, 1844, Area, .Sp. 118. — {Barhatia) sculptilis, Reeve, Edg. Smith. Rep. Lamellibranchiata of the Challenger Exped., p. 262. — (Acar) — — KoBELT in Martini u. Chemnitz, Concliyl. Cabin., Vlll, 2 Abth , p. 193, No. 175, pi. 46, tig. 14. Common between Koh Lan and Koh Mak, many specimens in 1 — 38 fathoms, sand, mud, gravel and shells. Long. 2—13 mm. Distribution: — Bombay (Mf:lvill & Abercrombie, A. Zebuensis, Reeve), Karachi (Melvill & Standen). — Amboina (Challenger), Philippines (Reeve), Torres Strait. (Melvill & Standen). Lamy (Journ. de Conchyl., vol. 55, 1907, p. 100) identifies A. sculptilis, Reeve, with A. afra, Gmel. var. solida, Sow. I do not think that he is correct in so doing. Apart from other considerations the ditTering geographical distributions of A. afra, Gmel. (= A. pisolina, Lam.), A. solida, Sow., and A. sculptilis, Reeve, are at once conspicuous; besides, it seems to me that A. sculptilis may very well be ' As communicated by letter. 15* llfi 20 separated from (he two other forms mentioned above, at any rate as far as the specimens from the Gulf of Siam are concerned. These agree entirely with the diagnosis and figure by Reeve, and also with the excellent description by Edgar Smith of A. sciilptilis. They do not at all resemble the figure of Lamarck's original specimen olA.pisolina (in Journal de Conchyl., vol. 52, 1904, pi. 5, figs. 6—7); neither do they agree with Reeve's diagnosis and figure of his species A. solida. The great number of specimens which I have before me all show a while colour under the thin epidermis. A. Zebuensis, Reeve, is undoubtedly synonymous with A. sciilptilis. Area (Fossularca) tenebrica, Reeve. Aren tenebrica, Kkevk, Proc. Zool. Soc. London, XII, 1844, p. 126. — - — Conctiol. icon., II, Area, Sp. 105. — (Barbatia) tenebrica, Rkeve, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 156, pi. 39, figs. 7-8. — — — — Edg. a. Smith, Report on tlie zoolog, collect, made during tlie voyage of H. M.S. "Alert," 1884, p. 110. — (Fossularca) — — Lamy, Joiirn. de Conchyl., vol.55, 1907, p. 105. Coast of Lem Ngob (1). North end of Koh Chang, 1 fathom, old coral blocks (4). Koh Chang, between stones at very low tide (46). Gulf at the south end of Koh Chang (1). Strand of Koh Kahdat (•/2). Long. 7 — 16 mm. Distribution: — Bombay, Karachi (Melvill & Standen). — Philippines, Japan (Nagasaki). Port Essington, Port Curtis. The epidermis is extremely velvet-like in several of the specimens from the Gulf of Siam, and the outline in this species varies rather considerably. Area (Acar) plicata, Ch. Area plicata, Chemnitz, Conchyl. Cabin., XI, 1795, p. 244, pi. 204, lig. 2008. — {Acar: plicata, Chemnitz, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 195, pi. 47, fig. 5. — — — — E. Lamy, Bull, du Mus. d'Hist. Nat. Paris, 1904, pp. 274-75. — — — — — Journ. de Conchyl., vol. 55, 1907, p. 80. - Hull, du Mus. d'Hist. Nat. Paris, 1906, p. 317. — squamosa, Lamarck, Anim. sans vert., VI, part. 1, 1819, p. 45, No. 35. — éd. 2, VI, p. 474, No. 35. — — — Savigny, Descr. de l'Egypte. Mollusques, pi. 10, fig. 6. — — — Lamy, Journ. de Conchyl., vol. 52, 1904, p. 142. Barbatia squamosa, Lamarck, Phitchard and Gatliff, Proceed. Roy. Soc. Victoria, vol. 17, part. 1, 1904, p. 241. Area Domingensis, — Anim. sans vert., VI, part. 1, 1819, p. 40, No. 16. — éd. 2, VI, p. 467, No. 16. — — — Lischke, Japan. Meeres-Conchyl., II, p. 142 u. Ill, p. 107. — (Acar) domingensis, Lamarck, Ed. A. Smith, Lamellibranchiata of the Challenger Exped., p. 265. — gradata, Uroderip and Sowerby, Zoolog. .Journal, IV, 1829, p. 365. — — _ . _ Gray, Zool. of Beechey's Voyage, p. 152, pi. 43, fig. 1. — — — - — Hanley, Ree. biv. shells, p. 155, pi. 18, fig. 39. — — — - — Reeve, Conchol. icon., II, Area, Sp. 92. Byssoarca divaricata, Sowerby, Proc. Zool. Soc. London, I, 1833, p. 18. Area — — Reeve, Conchol. icon. II, Area. Sp. 108. 21 117 Bijssoarrn piisilla, Sowkhhy, I'roc. Zool. Soc, I, 1833, p. 18. Area — — Reeve, C'.onchol. icon., II, Area, Sp. 112. — donticiformis, Heeve, Coiichol. icon., II, Area, Sp. 104. — (Byssoarca) pholadiformis, C. B. Adams, Shells coll. at Panama, 1852, p. 260. ttarhalia [Acar) himinata, Angas, Proc. Zool. Soc, 1865, pp. 697 and 655. Area {Bijssoarca) dubia, Baird, Brenchlev, Jottinjjs during the cruise of H. M. S. (^uiaijoa among the South Sea Islands. 1873, p. 453, pi. 42, figs. 5- 6. — M' CoYi, Tenison-Woods, Transact, and Proc. Roy. Soc. Victoria, vol. XIV, 1878, p. 61. Gulf of Slam ('/a). Long. 15 mm. Distribution: — Gulf of Manaar, Mangalore (Malabar Coast), Maldive Archip., Arabian Sea, Gulf of Oman, Persian Gulf, Gulf of Aden, Red Sea, Gulf of Suez, Mozambique, Natal coast, Seychelles, Amirantes, Madagascar, Mauritius, Cape of Good Hope, St. Helena, Ascension, Annobon, St. Thome, Cape Verd Isis., Madeira. — Tonkin, South Japan, Philippines, Moluccas, Torres Strait, North, East and South Australia, Tasmania, the South Sea Islands, New Caledonia. — West coast of America from St. Barbara to Peru; East coast of America: Bermudas, Florida, Gulf of Mexico, Bahamas, Greater and Lesser Antilles. The wide distribution of this species, together with its great tendency to varia- tion, has caused it to have numerous names given to it in the course of time. LiscHKE, ^ and more recently Ed. Lamy, ^ have recorded a great many of these. A. H. Cooke' doubts the correctness of Lischke's views upon the identity of these species; he is of opinion that they are three well-distinguished forms: gradata (the West American form), üomingensis -f squamosa (the West Indian form), divaricata, Sow. = plicata, Ch. (the East Indian form); but the distinguishing characters recorded by him are not valid. I have at my disposal a fairly large quantity of material of il. Domingensis from the West Indies, and the extensive variation-series includes, as far as I can see, all the forms which have been established. I think, W. H. Dall is mistaken when he' reiers A. Domingensis, Lam., and gradata, Brod. & Sow., from the Gulf of Mexico and the Caribbean Sea to A. reticulata, Ch. He sup- poses that A. congenita, Edg. A. Smith, also, is possibly only a form oi A. plicata, Ch. Area (Acar) tenella, Reeve. (PI. 1, Figs. 11 — 13J. Area tenella. Reeve, Proc. Zool. Soc. London, XII, 1844, p. 124. — — — Conchol. icon., II, 1844, Area, Sp. 91. — (Barbalia) tenella, Reeve, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abtli., p. 155, pi. 39, tigs. 5—6. Barbatia mollis. Dunker, Novitates concholog., 1867, p. 92, pi. 31, figs. 2 — 4. Area (Biirbatia) mollis, Dunker, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 128, pi. 33, figs. 5 — 6. — {Acar) tenella. Reeve, Lamy, Journ. de Conchyl., vol. 55, 1907, p. 93. ' Japanische Meeres-Conchylien, II, p, 142, III, p. 107. -' Journal dc Conchyliologie, vol.52, 1904, pp. 142— 47, and vol.55. 1907, pp. 80-87. ^ Annals and Magazine of Nat. Hist., 5. Ser., vol.18, 1886, p. 94. * Report of the Mollusca of the "Blake' Expedition, I, 1886, p. 242. 118 22 Koh Lan, 30 fathoms, mud (Va). Long. 19 mm. Di-stribulion: — Laccadive and Maldive Archip., Djibouti (Lamy), Isle of Bourbon (Deshayes), Madagascar. ~ Philippines, Torres Strait, Viti Isis., Funafuti (Ellice Isis.), Samoa Isis. In the specimen from the Gulf of Siam the ribs are not markedly granu- lated. Prof. Ed. v. Martens, whom I asked to compare the specimen with Dunker's original specimen, informed me that it "stimmt ganz gut zu den Original Exem- plaren von A. mollis, Dunk." Area (Anadara) granosa, L. Area granosa, Linnk, Syst. Nat, ed. X, 1758, p. (!94, No. 146. - ed. XII, p. 1142, No. 176. — ed. XIII, p. 3310, No. 18. — Mus. Ludov. Ulr., p. 519, No. 93. _ _ _ Chemnitz, Conchyl. Cabin, VII, p. 219, pl. 56, flg. 557. _ — — Reeve, Conchol. icon., II, Area, Sp. 15. — {Anomalocardia) granosa, Linné, Maiitini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abtii., p. 38, pi. 3, flg. 7. — (Anadara) — Lamarck, Morlet, Journ. de Conchyl., vol. 37, 1889, p. 162. — granosa, Linné, Ed. Lamv. Journ. de Conchyl,, vol. 52, 19Ü4, p. 158. — loc. cit., vol. 55, 1907, p. 210. — (Anomalocardia) granosa, L., Dautzenberg & Fischer. ,Iourn. de Conchyl., vol. 53, 1905, p. 193. Coast of Lem Ngob (1). Coast of Koh Chang (»/2). Isles of the Gulf of Siam (L. Morlet). Long. 27—47 mm. Distribution:— Malacca, Mergui Archip., Bassein river (Burma), Nicobars, Madras, Tranquebar, Gulf of Manaar, Bombay. — Cochin China, Tonkin, China, Japan (Nagasaki, Kodzuka), Philippines, Sumatra, Java, Borneo, Celebes, Moluccas (Lucipara, Ceram, etc.), Timor, Macassar, Aru Isl., Sorong. According to E. v. Martens ^ this species occurs frequently in brackish water at Singapore, on Borneo, Celebes, Sunda Islands and other places. M. v. Neumayer states^ that an "Area granulosa L. var. minuta" was found among fresh-water shells ("und zwar mit Arten der Gattungen Vivipara, Bythinia, Melania und Corbicula") in the deposits of the Yang-tse-kiang delta. This is nearly certainly a form of A. granosa which lives here in brackish water under conditions similar to those prevailing in the localities' stated by v. Martens. Area (Anadara) oblonga, Phil. Area oblonga, Phiijppi, Abbild, u. Beschreib, neuer od. wenig gekannt. Conchyl., 111, 185L p. 85 (17), pl.5. fig. 6. — (Anomalocardia) oblonga, Philippi, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 103, pi. 27, Hgs. 7-8. — (Anadara) — — P. Fischer, Catal. d. Moll, de l'Indo Chine, p. 215. ' Zoolog. Ergebnisse einer Reise in Niederländ. Ost-hidieii hrsg. v. M.Weber, IV, 1897, p. 228. "^ Wissenschaftl. Ergebnisse d. Reise d. Grafen Bêla Széchenyi in Ostasien, 1877—80, II, 1898, p. 641, pl. 1, fig. 4. ■* compare also about its occurrence in the Bassein river, in Journ. of the Asiatic Society of Bengal, vol. 36, 1867, p. 70. 23 119 Coast of Koh Chick ('/s). Sound of Koh Chang, 3—5 fathoms, soft clay, very common, taken in great numbers. Coast of Lem Ngob ('/2). Between Koh Kul and Koh Kahdat, 10 fathoms, shells (-2). Bangkok (Siam) Coll. Dautzenberg (P. Fischer loc. cit.). Long. 2 — 27 mm. Distribution: — Salanga, on the west coast of Malacca (v. Martens). Mergui Archip. (Philippi). It seems to me that there is a very close conformity and even transition, between the forms representing the series: — oblonga, Phil. — oblonga, Dunker* — nodifera, Martens^ — paucigranosa, Dunker.' I feel practically certain that all these forms should be referred to one species. Anomalocardia pulchella. Dunker,' is, no doubt, simply the present species. Philippi's statement' tiiat "Die Area ist ganz vom schwarzen Ligament eingenommen" has, in Kobelt's diagnosis (Martini u. Chemnitz, loc. cit.), been altered to "das schwarze glatte rautenförmige Band lässt vornen und hinten ziemlich viel Raum frei;" this agrees also with the specimens from the Gulf of Siam. Ed. Lamy'' considers A. oblonga, Phil., to be a form of A. granosa L. Area (Anadara) subrubra, Dunk. Anomalocardia subrubra, Dunker, Novitates conchologicæ, 186G, p. 83, No. 92. pi. 28, figs. 1 — 3. Area (Anomalocardia) subrubra. Dunker, Korrlt in Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. Ill, No. 83, pi. 29, figs. 4— 5. — (Anadara antiquala L. var. subrubra, Dunker, Lamy, .lourn. de Conchyl., vol. ,^i5, 1907, p. 200. Koh Chuen, 30 fathoms {^k). Long. 13 — 15 mm. Distribution: — Philippines. ' Novitates conchologicæ, p. 85, pi. 29, figs. 7 — 9. recorded to have been taken at the Mergui Islands. - Proc. Zool. Soc. London, part 28, 18G0, p. 17. Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 46, pi. 13, figs. 3 — 4. Recorded from Bangkok and Java by E. v. Martens who ("Zool. Ergebnisse ein. Reise in Niederländ. Ost-Indien hrsg. v. M.Weber," 1897, p. 228) states that it is sold as food in Bangkok, and that it lives in brackish water in these localities. It is a misprint when v. Mautkns (loc. cit.) states, that A. nodifera is "17 mal so lang als hoch.'" ' Novitates conchologicæ, p. 85, pi. 29, figs. 10—12. Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 100, pi. 27, figs. 1 — 2. Kobelt is also of opinion (in the last-mentioned work) that A. pauci- granosa. Dunker is only a more feebly sculptured example of A. nodifera. Dunkek records it from "Siam." * Novitates conchologicæ, p. 113, pi. 38, figs. 6—9. Dunker records it from "Japan." R. Stearns from the east coast of Nippon. As Reeve had already in 1844 employed the same specific name for an Area (Acar) from the Mediterranean, Dunker's name must certainly be altered. (For the reasons which justify the adoption of Reeve's name A. pulchella, for the Mediterranean species instead of A. imbricata, Poli, see "Bucquoy, Dautzenberg et Dollfuss, Les Mollusques mar. du Roussillon," II. p. 190). •' Abbild, u. Beschreib, neuer od. wenig gekannt. Conchyl. (loc. cit.). '■ ,Iourn. de Conchyl., vol. 52, 1904, p. IfiO, and vol. 55, 1907, p. 210. 120 24 Area (Anadara) uropygomelana, Bory. Area uropigimelana, Boiiv de Si Vincent, Encyclopédie method., 1797, pi. 307, fig. 2. — (Anomalocardia) uropygmelaim, Bory, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth.. p. 85. pi. 23, figs. 5-6. — {Anadara) uropygmelana, Bory de Saint-Vincent, Lamy, Bull, du Mus. d'Hist. Nat. Paris, 1904, p. 277. — — — — — Journ. dc Conchyl., vol. 55, 1907, p. 207. — holoserica, Reeve, Proc. Zool. Soc. London, XII, 1844, p. 39. — — — Conchol. icon., II, Area, Sp. 11. — — - MoRLET, ,Iourn. de Conchyl., vol. 37, 1889, p. 162. — {Anadara) holosericea, Reeve, P. Fischer, Catal. de Moll, de I'lndo-Chine, p. 216. — — holoserica, — Edg. Smith, Proc. ZooI. Soc. London, 1891, p. 431. MoRLET (loc. cit.) states that the present species {A. holoserica, Reeve) is taken at "Isles du golfe de Slam." Lamy, however, points out (Journ. de Conchyl., vol. 55, 1907, p. 242) that this statement is due to erroneous determination hy Morlet, and that the specimens belong to Area cornea, Reeve var. Cecillei (Phil.), Lamy (compare this species). Nor did the Danish Expedition to Siam collect any specimens of A. uropygomelana, Bory (= A. holoserica. Reeve). Distribution: — Salanga (Malacca), Felidu Atoll and Hulule Isl. (Maldive Archip.), Gulf of Aden, Red Sea, Mauritius, Madagascar, Seychelles, East Africa, Querimba Isis. — Philippines, Java, Togean Isis., Moluccas, Gilbert Isis. (Kingsmill), New Caledonia. Sturany* states that a specimen (of A. scapha, Chemn.) resembling A. holo- serica, Reeve, has been taken at Ras Abu Somer (Red Sea). W. J. Hall and R. Standen state" that A. uropygomelana, Bory, has been taken on "a raised coral reef" at Port Sudan, near Suakim, on the west coast of the Red Sea. Lastly, Lamy states" that specimens from the Red Sea are in the Paris Museum. Area (Anadara) Mortenseni, n. sp. (PL il. Figs. 1-2). This shell is oval, thin, and rather ventricose. The front passes evenly and with rounded outline into the ventral side, while the hinder part is more straightly truncate, and forms a rounded angle with the ventral part. Il is white, and bears about 47 sharp radiating ribs which are closely covered with small, regularly-arranged nodules and scales, crossed by fine, concentric lines of growth which give the surface a beautiful, reticulated appearance. Not all the radiating ribs extend over the unibones, but many unite with an adjacent rib. The inter- stices between the ribs are generally narrower than the ribs, and are finely sculp- tured. A keel, upon which the radiating ribs are further apart and stouter than are the other ribs, extends from the umbones towards the posterior part of the ventral side. Owing to this keel, the well-raised, prominent umbones become oblique, and are higher towards the hinder part. The umbones are situated at about the middle of the shell, a trifle nearer its anterior end. The ligament-area is small and narrow. There are about 25—26 hinge-teeth, divergent on each side of the centre. The interior is white; the exterior ribs are there slightly noticeable, and ' Lamcllibr.Tiichiaten d. Rothen Meeres, 1899, p. 36. - .lounial (if Conchology, vol. 12, 1907, p. 68. ' h>c. cit., .louin. de Conchyl., 1907, p. 209. 25 121 they are deeper only at the place where the keel is situated exteriorly; the margin is crenulated. Long. 12 mm., alt. 9 mm. West of Koh Kill, 30 fathoms, sand and mud. This pretty little, characteristic species, of which unfortunately only a single left valve is at hand, has certainly been provided with an epidermis, but no trace of it is visible. I have taken the pleasure of associating with this new species the name of Dr. Th. Mortensen, who, during the Danish Expedition to Siam, made such excellent collections of Molluscs, in a place of which the fauna had been, hitherto, but slightly known. Area (Anadara) cornea, Reeve var. Cecillei (Phil.), Lamy. Area [Scapharcw Cecillei Phii.ippi, Kohei.t in Mahtini u. Chf.mmtz, Coiich3'l. Cabin., VIII, 2 Abtli , p. 105, pi. 28, ngs. 3—4 (non pi -10, figs. 2^3). — (Anadarcr cornea, Reeve var. Cecillei. Philippi, Lamy, Journ. de Conchy!., vol.55, 1907, p. 241. The Gulf of Slam (Pavie, 1885). The Danish Expedition to Siam collected no specimens of this species. Distribution: — Philippines. MoRLET (Journ. de Conchyl., vol. 37, 1889) had identified the specimens col- lected by Pavie as A. boloserica, Reeve. Lamy (loc. cit.), however, points out that they were erroneously determined, and that they belong to the present form. For further details reference should be made to Lamy (loc. cit.), whose view of the synonymy I have adopted. Area (Anadara) auriculata. Lam. Area auriculata, Lamarck, Hist. nat. d. anim. s. vert., 1819, VI, part. 1, p. 43. — éd. 2, VI, 1835, p. 472. — — — Delessert, Recneil de coquilles décr. p. Lamarck, pi. XI, fig. 12. — — — L. Mori-et, Journ. de Conchyl., vol.37, 1889, p. 1()2. — — — Lamy, Journ. de Conchyl., vol. .52, 1904, p. 156. — loc. cit., vol. 55, 1907, p. 217. "Iles du golfe de Siam." Morlet (loc. cit.). The Danish Expedition to Siam collected no specimens of this species. Distribution: — How far the species from the "l'Océan indien," described by Lamarck, is the same as that which various authors record from the West Indies, I am not prepared to say. Savigny's figure ' of A. auriculata, Lam. (recorded by IssEL- from the Red Sea), can scarcely be Lamarck's species, which, also, has not since been recorded as found in the Red Sea. Ihering' records it from S.Paulo (Brazil), but this seems very improbable, and I venture to suggest that it is due to erroneous determination. ' Description de l'Egypte. Coquilles, pi. 10, fig. 8. - Malacologia del Mar Rosso, 18G9, p. 88. ' .lourn. de Conchyl., vol.43, 1895, p. 213. 1). K. !>. Viderlsk. Selsk. Skr.. 7. R.xkke, naturvidensk. o^ m.TUicm. Alii. V. :î. 16 122 26 Area (Scapharca) globosa, Reeve. Area globosa. Riîevk, Proc. Zool. Soc. London, XII, 1844, p. 45. — — - Conchol. icon., II, Area, Sp. 52. — (Anomalocarditi) globosa, Bhhvr, Martini u. Chf.mmtz, Conchj'l. Cabin., VIII, 2 Abtli., p. 203, pi. 48, fig. 4. — globosa, Reeve, Cnos.sE et Fi.scher, Journ. de Conchyl., vol.37, 1889, p. 292. 9 — (Seapharea) gZofcosa, Reeve, an A.Bhandtii, Phii.ii'pi?, P. Fischer, Catal.d. MoIl.de I'lndo-Chine, p. 210. — globosa, Reeve, Lamv, Journ. de Conchyl, vol. 55, 1907, p. 260. "Siam" (P. Fischer, loc. cit.). The Danish Expedition to Siam collected no specimens of this species. Distribution: Annam, Philippines. P. FiscHEii (loc. cit.) as slated above, doubts the correctness of the determination. Area (Scapharea) rhomboidalis, Ch. Area rhomboidalis, Chemnitz, Conchyl. Cabhi., VII, 1784, p. 210, pi. 56, fig. 552. — — — Nyst, Mém. de I'Acad. roy. d. sc. de Belgique, XXII, p. 62. — inaequivalvis, BiiuoriERE, Encyclop. method.. I, 1792, Hist. nat. d. vers., p. 106. — — — Lamarck, Anim. sans vert., 2 éd., VI, p. 472, No. 30. — — — Encyclop. method., pi. 305, fig. 3a. — — — Reeve, Conchol. icon., II, Area, Sp. 54. — — — KoBELT in Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 40, pi. 3, fig. 1. — hispida, Philippi, Abbild, u. Beschreib, neuer od. wenig gekannt. Conchyl., III, p. 86 (18), pl. V, fig. 4. — disparilis, Reeve, Conchol. icon., II, 1844, Area, Sp. 59. — — — Lamy, .lourn. de Conchyl., vol. 55, 1907, p. 256. Coast of Lem Ngob ('/s). Sound of Koh Chang, 5 fathoms, soft clay (^/a). West coast of Koh Chang, 1 fathom, old coral blocks (1/2). W. of Koh Kut, 30 fathoms, sand and mud (^/a). Between Koh Kut and Koh Kahdat, 6 fathoms, clay mixed with sand (''/a). Same locality, 10 fathoms, shells (^/a). S. of Koh Bidang, 9 fathoms, mud (^/a). Long. 4-50 mm. Distribution: — Salanga, Mergui Isis., Madras, the Gulf of Manaar, Panjim and Goa, Bombay, Persian Gulf. — Philippines, Moluccas, Borneo, Java, Timor. Lamy is of opinion that the Area inaequivalvis of Bhuguière and of Reeve is not identical with that species as defined by Kobelt; therefore he places Kobelt's form as a synonym of Å. disparilis, Reeve (= A. rhomboidalis, Chemnitz), while he separates A. inaequivalvis (Bruguière), Reeve, as a distinct species. Area (Seapharca) vellicata, Reeve. ,4rc(i ncllicaln. Reeve, Proc. Zool. Soc. London, 1844, p. 42. — Conchol. icon., 1844, II, Area, Sp. 33. — {Scaph<(rca; ocUicata, Reeve, Kobelt in Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 177 pl. 44, fig. 1. — [Anadaral — — Lamv, .lourn. de Cochj'l., vol. 55, 1907, p. 251. 27 123 Koh Chuen. 30 Inlhoins (1). Between Koh Kut and Koh Kahdal, 10 fathoms, shells (i'V'ä). S. of Koh Kahdat, 8—10 fathoms, mud (''/ä). Long. 4—15 mm. Distiihution: — Ceylon (Hanley), Mascat (Brit. Mus.), Red Sea (fossil, Issel). — China (Collect, de l'École d. Mines, Paris). All the specimens from the Gulf of Siam are small, but correspond well with Reeve's diagnosis; the valves are thin; in the specimens without an epidermis there is a distinct intercostal-sculpture between the 46 radiating ribs; the angular transi- tion, mentioned as occurring between the hinder and lower margins, is more rounded than is shown in Reeve's figure; the characteristic groove upon the umbones is very pronounced in quite small specimens. Area (Scapharca) crebricostata, Reeve. Area crebricostala. Reeve, Proc. Zool. Soc. London, XII. 1844, p. 46. — — — Conchol. icon., II, Area, Sp. 61. — — — Chosse et FiscHEH, Journ. de Conchyl., vol. 37, 1889, p. 292. — (Scapharca) crebricostala. Reeve, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abtli., p. 91, pi. 25, figs. 3—4. — {Anadara — — P. Fischer, Catal. d. Moll, de Ilndo-Chinc, p. 216. — — — — L.^MY, Journ. de Conchyl., vol. 55, 1907, p. 253. Koh Mak, sand coast {-'l-i). On the coast of Koh Kahdat (^/s). Long. 29 — 49 mm. Distribution: — Cochin China, Annam. I cannot make the great number of ribs (43 — 44), stated by Reeve and Kübelt, agree with the figures given by the same authors, which apparently show only about 35 — 37. Neillier are so many ribs found in the specimens from the Gulf of Siam (in which there are only about 35), unless the most anterior, duplicate ribs are to be counted twice. Area (Scapharca) clathrata, Reeve. Area chilhrala, Reeve, Proc. Zool. Soc. London, XII, 1844, p. 44. — — — Conchol. icon., II, Area, Sp. 48. — iAnomalocardia] clathrata, Reeve, Maktini u. Chemnitz, Conchyl. Cabin., VIII, 2 Ablli., p. 17'.l, pi. 44, fig. 5. — {Scapharcai — — Edg. A Ssiith, Rep. Challenger Lamellibranchiata, p. 2()6. — {Anadara} — — Lamv, Bull, du Mus. d'Hist. Nat. Paris, 1904, p. 277. — - _ _ _ Journ. de Conchyl., vol. 55, 1907, p. 229. Seiipharca iiiminiva, H. Adams, Proc. Zool. Soc. London, 1872, p. 11, pi. 3, fig. 15. Area — — Cooke, Ann. and Mag. of Nat. Hist., 5 Ser., vol. 18, 1886, p. 94. Common belween Koh Lan and Koh Kut, many specimens in 1—30 fathoms, mud, sand, clay, and shells. Long. 3—33 mm. Distribution: — Madras, Felidu Atoll (Maldive Archip.), Gulf of Oman (Melvill & Standen), Gulf of Aden, Red Sea, Suez. — Philippines, Amboina, Torres Strait, Mast Head Reef (Queensland). 16" 124 28 In Reevk's diagnosis, and in the descriptions of A. clathrala given by later authors, I do not find any mention of several distinctive characters, peculiar to this species. Thus, in the specimens from the Gulf of Siam, the sculpture is diflerent on the two valves; on the right valve it is only the 8 — 10, most anterior ribs which are set with regularly-arranged, small nodules which gradually disappear almost completely from the rest of the ribs; also, on the right valve, all the ribs are somewhat flatter than are those on the left valve. The latter is more strongly sculptured, and on the 18 — 20 most anterior ribs the small nodules occur regularly and distinctly, like strings of beads; but they are frequently absent from the most posterior ribs. Upon both the umbones there is a distinct median groove, which occurs in all the specimens, from the smallest to the largest, and which affords a good distinguishing feature by means of which they may be separated from forms nearly related to them. A. H. Cooke' considers A. rotundicostnta, Reeve, to be synonymous with the present species. I believe the same is the case with A. Troscheli, Dunker.^' Edg. Smith ' doubts Reeve's statement that the epidermis is "very finely bristly between the ribs;" but among the specimens from the Gulf of Siam there are several in which this can be seen, and the bristles in such cases, are parti- cularly strongly developed between the most posterior ribs. Specimens, however, also occur, with a perfectly well preserved epidermis, from which these bristles are entirely absent. As the present species is provided with a byssus, it cannot be referred to the sub-genus Anadara, but must belong to Scapharca.^ The Siam Expedition brought home several specimens in spirit which show a well-developed byssus. Area (Scapharca) consociata, E. Sm. Area {Scapharca?} consociata, Eug. A. Smith, Challenger Exped. Report on the Lamellibranchiata, 1885, p. 266, pi. 17, lig. 7. — — — Martini u. Chemnitz, Conchyl. Cabin, Vlll, 2 Abth., p. 221. — consociata, Edu. A. Smith, Ann. and Mag. Nat. Hist , 7 Ser., vol. 14, 1904, p. 12. W. of Koh Chuen, soft clay {^^h young specimens). S. of Koh Samit, 30 fathoms, mud ('/s). Off Tung Kaben, 6 fathoms, clay mixed with sand Qh). Sound of Koh Chang, 4—5 fathoms, soft clay (3 4- ''/2). West coast of Koh Chang, 10 fathoms, mud (1). E. of Koh Mak, 20 fathoms, mud (2). Between Koh Kahdat and Koh Kut, (5 fathoms, clay mixed with sand (^/a). Long. 2—38 mm. (long. 38, alt. 27. — long. 26, all. 18). Distribution: Off Chedubar (Aracan coast, 20 30 fathoms, Smith). — Arafura Sea (Smith). As may be seen from the measurements given above, Edg. Smith is right in believing that his specimen with a length of 125 mm., collected during the Chal- lenger Expedition, is not full-grown. ' Annals and Magazine of Nat. Hist. 5 Ser., vol. 18, 1886, p. 95. - Index MoUuscor. mar. Japonici, p. 234, pi. 14, figs. 14 — 15. => Proc. Zool. Soc. London, 1891, p. 432. ' EiHi. A. Smith, who, in the Challenger Report, 1885, refers A. clallirata to the sub-genus Scapharca, ill 1891 (loc. cit. p. 432j had changed his opinion, and placed it under Anadara. 29 l'-^5 Area (Scapharca) dichotoma, Desh. (I'l. 11, Kig. :i-i). Area dichotoma, Deshayes, Coiichyl. de l'ile de la Reunion (Bourbon), 1863, p. 22, pi. 3, figs. 18— 19. — {liarbdtiit?] dichotoma, Deshaves, Mahtim u. Chemnitz, Concliyl. Cabin., VIII, 2 Abtli., p. 2!), pi. 8, ligs. 7 8. W. of Koh Chuen, soft clay and mud ('/s). S. of Koh Tuhi, 10 fathoms, clay mixed with sand (',4). Between Koh Kahdat and Koh Kut, 6 fathoms, clay mixed with sand ('2). W. of Koh Kut, HO fathoms, sand and mud ('/2). Long. 7 — 17 mm. Distribution:— Bourbon (Deshayes). Professor Ed. v. Martens, to whom I sent specimens from Koh Kut, has kindly determined these as A. dichotoma, Desh. This species differs, however, in several respects from the specimens from the Gulf of Siam, which have 25 ribs, all of which (except the last two at the anterior end) are divided by a narrow median groove into two ribs of about the same breadth, and covered with regularly-arranged small nodules. As the median groove does not begin quite at the umbo, specimens measuring, for example, about 5 mm. in height scarcely have the ribs at all divided. The interstices between the double ribs are about as broad as the ribs and bear close-set transverse lines. The keel, mentioned by Deshayes, which divides the median part from the posterior end, and which, in his specimens bears four undivided ribs, does not occur in the Siam specimens; whether this is owing to individual or specific character, may be known later; at present I shall name the form from the Gulf of Siam, which we are here considering. Area dichotoma, Desh. var. gratiosa. Area (Scapharca) Sabinae, Mori. Area Amidanii Sabinic, L. Morlet, Journ. de Conchyl., vol. 37, 1889, p. 189, pi. 8, fig. G. — tScapharca) — — Chossk et Fischek, Journ. de Conchyl., vol.37, 1889, p. 292. — - — — P. Fischek, Catal. d. Moll, de 1 Indo-Chine, p. 21(j. — {Amidaraj — — Mission Pavie Indo Chine, Etudes diverses. 111, 19U4, p. 378, pi. 22, fig. 6. — iCuncarca) — — Lamy, Journ. de Conchyl., vol.55, 1907, p. 276. Coast of Koh Chick (10/2). W. of Koh Kut, 15 fathoms, mud ('/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (Ws). Strand of Koh Kahdat ('/a). Phu Quok in the Gulf of Siam (Moklet). Long. 9-17 mm. Distribution: — Ceylon. — Annam (Cochin China). The shells from the Gulf of Siam are rather inequilateral, and not so regularly formed as that figured by Moulet; they agree most closely with the description which Crosse & Fischer give of the individuals from Annam. Area (Scapharca) gubernaculum, Reeve. Area (jiilternavulnm. Reeve, Proc. Zool. Soc. London, XII, 1844, p. 40. — — — Conchol. icon., II, Area. Sp. 14. — — — Edg. a. Smith, Lamellibranchiata of the Challenger E.\p.. p. 266. 126 30 Area tjubcinaciilum, Hiiiivii, Mautini u. Chemnitz, Conchyl. Cabin,, VIII, 2 Abtli., p. 1U7, pi. 28, ligs. 5—6. — — — P. Fischer, Catal. d. Moll, de Ilndo-Cliine, p. 272. — [Antidara; giibernaculum, Rrkvk, Lamy, .louni. de Conchyl., vol. ,'>5, 19U7, p. 23!). — chdlciinllunn, Ki;kvi;, I'roc, Zool. Soc. London, XII, 1844, p. 44 (fide Edg. Smith). — — — Conchol. icon., II, Arcix, Sp. 43. — Lnzonica, Rkevi;, Proc. Zool. Soc. London, XII, 1844, p. 44 (fide Edg. Smith). — — — Conchol. icon., II, Area, S. 44. "Golfe de Siam," L. Morlet (P. Fischer loc. cit.). The Danish Expedition collected no specimens of this species in the Gnlf of Siam. Dist libntion: — Philippines, China, Formosa, Port Jackson. Area (Scapharca) indica, Gm. (PI. II, Figs. 5-12). Area indica, Gmhlin, Syst. Nat., ed. XIII, 1790, p. 3312, No. 27 (excl. var.). ( — — — Lamarck, Anim. sans vert., VI, p. 473, No. 31). ( — — — Reevk, Conchol. icon., II, Area, Sp. .'Sfi). — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 11, pi. 2, fig. 2. — (Argina) indica, Gmei.in, Lamy, Journ. de Conchyl., vol. 55, 1907, p. 295. — Inditte Orientalis, Chemnitz, Conchyl. Cabin., VII, 1784, p. 196, pi. 55, fig. 543. Oslindisehe Bastariaretie, Martini, Beschäftig, d. Heilin. Gesellsch. Naturf. Freunde, III, 1777, pp. 288—90, pi. 6, fig. 13. Coast of Lem Ngob (''/a). Long. 21-44 mm., alt. 11—23 mm. Distribution: — Coromandel Coast (Tranquebar; Chemnitz). Hanley' records the species from Sumatra. In the Museum in Berlin are specimens from Sumatra; North-west Australia (Menke). This species is probably more widely distributed. By comparison with original specimens of Area indica, Gm., from Tranque- bar, from Spengleh's collection in the Zoological Museum of the University of Copenhagen, I have been able to identify the specimens from the Gulf of Siam. The present species has hitherto been badly figured and described. Lamarck, Reeve and Kobelt,^ all say, that the area is absent in the species; this is nol correct (Gmelin also does not mention it). Normally, there occurs an area which is rather narrow and striped' as shown in the figures, PI. II, Figs. 9 and 12; it is, however, frequently reduced to a minimum, and as the valves, thereby, have their unibones placed closely together, Ihe latter become much worn; [he hinge- teeth also suffering by this reduction of the area. The ribs, 30 — 36 in number, are flattened and broad. From the umbones downwards to the ventral margin the valves are frequently somewhat concave in the middle. Reeve's figure certainly ' Catalogue of recent bivalve shells, p. 158. As Hani.ey in mentioning this species says: "with many ribs, which are grooved in the middle" it can hardly be the present species. '' Martini & Chemnitz, Conchyl. Cabin., loc. cit. ^ Chemnitz (loc. cit., VII, j). 197) says: "Der kleine zwischen den Wirbehi befindliche, etwas ver- tiefte Kaum wird von einen schwärzlichen lederartigen Bande bedecket." 31 127 does not represent Area indica, Gm., more probably it is A. campechensis, Gm. (= A. amerkana. Gray). Lamarck has also, undoubtedly, been mistaken with regard to A. indica, Gm. when, in his diagnosis, he says "testa ovata" and later on "costiis mediis sulco divisis." Ed. v. Mahtkns also supposes (as he writes in a letter to me) that Lamarck has fallen into the same error as Reeve, and has had, lor examination, a specimen of A. campechensis, Gm. Area (Trisidos) tortuosa, L. Area torlnosa, Linnk, Systema Naturæ, ed. X, 1758, p. 693, No. 139. — etl. XII, p. 1140, No. 1G8. - ed. XIII, p. 3305, No. 1; — Mus. Ludov. Ulr., p. 517, No. 89. — — — Lamaih-.k, Anim. s. vert., éd. 2, VI, p. 460, No. 1. — — — Reeve, Conchol. icon., II, Area, Sp, 86. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 7, pi. 1, figs. 1—2. — — — Crosse et Fischer, Journ. de Concliyl., vol. 37, 1889, p. 2D1. I'nnillelipedutn tortnosum, Linné, Morlet, Journ. de Conchyl., vol.37, 1889, p. 163. Area I'antllelepipediim tortuosa, Linné, Lamv, Journ. de Conchyl., vol.55. 1907, p. 108. — lorla, Steknstiui', Mduch, Catal. conchyl. quæ reliq. C. V. Kierulf, 1850, p. 33. — Catal. concljyi. qua- reliq. Yoldi, II, 1853, p. 40. NW. of Koh Chang, 10 fathoms, mud (1). Koh Lan, 30 fathoms, mud (1). W. of Koh Kut, 15 fathoms, mud ('/a). Between Koh Kahdat and Koh Kut, G — 10 fathoms, clay mixed with sand, shells (1 -j- ^/s). Islands in the Gulf of Siam (Morlet). Long. 10—28 mm. Distribution: — Malacca, Singapore, Madras, Gulf of Manaar, Bombay, Karachi, Persian Gulf, Gulf of Aden, Zanzibar. — Poulo Condor, Annam, China, Philippines, Bani^a-Strait, Moluccas, North-west Australia, Port Curtis (East Australia). Ed. Smith' is justified in rejecting Klein's name for the subgenus Parall- elepipedum, as it dates from 1753; but he should use Bolten's name Trisidos, dating from 1798, and should not employ, as he does, Oken's name Trisis, dating from 1815. Area (Trisidos) semitorta, Lam. Area semi-torta, Lamarck, Anim. sans vert., éd. 2, VI, 1835, p. 460. — semitorta, — Reeve, Conchol. icon., II, Area, Sp. 89. — (Parallelepipeclum) semitorta, Lamarck, Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 134, pi. 35, figs. 1—2. — (Triais) semitorta, Lamaiick, Eno. A. Smith, Report Challenger Lamellibr., p. 268. — [Parulletipipcilum) semitorta, Lamarck, Crosse et F'ischer, Journ. de Conchyl., vol. 40, 1892, p. 70. — — — — Lamv, Journ. de Conchyl., vol. 55, 1907, p. 109. Common between Koh Rin and Koh Kut, 1 — 38 fathoms, mud, sand and shells. The Gulf of Siam on the west coast of Cambodge (Crosse & Fischer). Long. 4 83 mn\. ' Report on the Lamellibranchiata of the Challenger-Expedition, p. 268. 128 32 Distribution:— Persian Gulf, Gulf of Aden, Madagascar (Voeltzkow). — Philippines, China (Hongkong, Shanghai), North Aifstralia, Torres Strait, Tasmania (?). Area (CucuUaea) concamerata, Mart. Area concamerata. Martini, Beschaff, d. lieilin. Gesellsch. Naturf. Kreunde, III, 1777, p. 292, pi. VII, figs. l.'j-Ki. — cucuUata, — Conchyl. Cabin., VII, p. 174, pi. 53, figs. 526-28. — Cucullus, Gmki.., Syst. Nat., ed. XIII, p. 3311, No. 23. CucuUœa auricuUfera, Lamarck, Anim. s. vert., éd. 2, VI, p. 454. — concamerata, Martini, Reeve, Conch, icon., XVII, Cnculkea, .Sp. 1. CucuUaea — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abtli., p. 5, pi. 1, figs. 3— 4; pi. 5, figs. 1—2. Cucullœa — — Lamy, Journ. de Conchyl., vol.55, 1907, p. 30G. Cucullœa granulosa, Jonas, Proc. Zool. Soc. London, XIV, 1846, p. 34. — — Reeve, Conch, icon., XVII, Cucullwa, .Sp. 2. — — Lamy, Bull, du Mus. d'Hist. Nat. Paris, 1904, p. 278. — Journ. de Concliyl., vol. 55, 1907, p. 306. Ivoh Lan, 30 fathoms, mud (1). Koh Chuen, 10—30 fathoms (2'/3). Between Koh Chuen and Koh Chang, 15 fathoms, mud (4). S. of Koh Samit, 14-18 fathoms ('/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (2). E. of Koh Mak, 20 fathoms, mud (1). The Gulf of Siam, on the west coast of Cambodge (H. Crosse & P. Fischer, C. granulosa, Jon.). ' Long. 4—92 mm. Distribution: — Singapore, Mergui Archip., Nicobars, Madras, Tranquebar, Ceylon, Persian Gulf, Gulf of Aden, Red Sea (subfossil), Seychelles. — China, For- mosa, Japan (Nagasaki), Torres Strait, New Caledonia. I have specimens at hand from the Gulf of Slam which, with respect to the number of the outer lateral teeth agree entirely with the description of CucuUaea granulosa, Jonas (Reeve). The number of the teeth in the latter form is, however, quite unreliable as a distinguishing mark, as the lateral teeth in at least the younger individuals (e. g. in individuals measuring 65 mm. in length) pass into the rest of the row of teeth without any interval or other separation. Pectunculus amboinensis, Gmel. Cardium amiwincnsc, Gmelin, Syst. Nat., ed. XIII, 1790, p. 3255, No. 43. Area pectunculus, Linné, part. Syst. Nat., ed. X, p. 695, No. 150. — ed. XII, p. 1142. No. 180. — — — Martini & Chemnitz, part., Conchyl. Cabin., Vll, p. 235, pi. 58, figs. 568-69. Pectunculus pcctiniformis, Lamauck, part. Hist. nat. d. anim. sans vert., VI, 1 part. 1819, p. 53, No. 16. — éd. 2. VI, 1835, p. 494, No. 16. — — — Reeve, Conchol. icon., I, Pectunculus, Sp. 11. — — — L. Morlet, Journ. de Conchyl., vol. 37, 1889, p. 163. — pectunculus, Linné, Edg. A. Smith, part., Proc. Zool. Soc. London, 1891, pp. 432— 33. > Journ. de Conchyl., vol. XL, 1892, p. 76. 33 129 Islands in the Gulf of Siani (L. Morlkt, loc. cit.). The Danish Expedition to Siam collected no specimens of this species. Distribution: — Mergui Archip., Ceylon (?). — Cochin China, Poulo-Condor, Philippines, Amboina. All the other localities recorded in the literature should no doubt be referred to "P. pectunculus L. (Edg. Smith.)" Edg. Smith (loc. cit.) is of opinion that Linné (under the name of Area pectun- culus), Lamarck, and others have confused two well-distinguished Pectunculus species; one species in which the interstices between the ribs are rather broad and well- marked as shown, for example, in Savigny's figure (Descript. de l'Egypte, Coquilles, pi. X, fig. 2), and another species (the one we are here considering) in which the broad ribs stand close to each other, separated only by a groove, without any well- marked interstices. Also, in the first-named species, the interior of the valves has a strong reddish-brown colour on the hinge-plate below the teeth, a feature which is said not to occur so pronouncedly in the other species; but I am in doubt how far the latter is a constant character. Limopsis cancellata, Reeve. Pectunculus ccincelhitus, Reeve, Proc. Zool. Soc. London, XI, 1843, p. 188. — — Conchol. Icon., I, Pectunculus, Sp. 39. Limopsis cancellata, Rekve, Edg. A. Smith, Report on the LamcUibranchiata of the Challenger Expedit., p. 25G. — Woodwardi, A.Adams, Proc. Zool. Soc. London, 1SG2, p. 231 (fide Edg. Smith!. — — — DuNKEH, Index molluscor. mar. Japon., p. 237, pi. XVI, figs. 5 — G. — Philippii. A. Adams, Proc. Zool. Soc. London, 18G2, p. 230 (lide Edg. Smith). Area multistriata, Fouskâi., Descript. animal, quæ in itin. orient, oljserv., 1775, p. 123 (fide A. H. Cooke). Pectunculus niultistriatus, ForskIl, Reeve, Conchol. icon., I, Pectunculus, Sp. 42. Limopsis multistriata, Forskål, Savigny, Descript. de l'Egypte. Coquilles, pl.X, fig. 3. — — — juv., A. H. Cooke, Ann. and Mag. Nat. Hist, 5 Ser., vol. 18, 1886, p. 95. W. of Koh Kut, 30 fathoms, sand and mud (''/3). Long. 2—6 mm., alt. 2 — 6 mm. Distribution:— Singapore, Gulf of Manaar, Arabian Sea (lat. 18° 25' N., long. 71° 45' E.; in 191 fathoms). Red Sea, Suez. — Japan, Torres Strait, Mast Head Reef (Queensland), Port Jackson. Limopsis Tenisoni, Ten. Woods (= L. cancellata, Ten. Woods non Reeve) from Tasmania and South Australia has been erroneously determined and referred to L. multistriata. Forsk. ' by Tate and May. Fam. Mytilidae. Mytilus (Chloromya) viridis, L. Mgtilus viridis, Linné, Syst. Nat., ed. X, 1758, p. 706, No. 220. — Mus. Lud. Ulr. 17G4, p. 542, No. 138. — Syst. Nat., ed. XII, 1767, p. 1158, No. 259. — — — Hamlet, Catalogue of reo. biv. shells, p. 247. ■ For further details cf. Proc. Roy. Soc. Tasnian., 1876 (1877), p. 156; 1877 (18791, p. 56. — Proc. Linn. Soc. New Soutli Wales, 1901, p. 437. — Scient, results of the trawling expedition of H. M. C. S. "Thetis" off tlie coast of New South Wales. Mollusca by C. Hedley, I, 1902. p. 297. I). K 1). Viilensk. SelsU. Skr., 7. R.Tekke, naturviilcnsU. o;; miithem. Afd. V. 3. 17 130 34 Mytiliis viridis, Linnk, Hamley, Ipsa Liniiæi Coiicliylia, p. 145. ~ — — Dautzenbehg & Fischer, Journ. de Conchyl., vol. 54, 1906, p. 211. — Smaragdinus, Chemnitz, Conchyl. Cabin., VIII, 1785, p. 166, pi. 83, fig. 745; pi. 84, fig. 746. — smaragdinus, — Reeve, Conehol. icon., X, Mytiliis, Sp. 28. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, S Abth.. p. 31, pi. 3, fig. 5; pi. 13, figs. 1-2. — — — V. Martens, Proc. Zool. Soc. London, 1860, p. 17. — — — L, Morlkt, .Journ. de Conchyl.. vol. 37, 1889, p. 161. — opallis, Lamarck, Hist. nat. d. aniin. s. vert., VI, part. 1, 1819, p. 124, No. 18. — éd. 2, VII, 1836, p. 43, No. 18. "Siam" (E. v. Martens, gathered by Mouhot). This species does not occur in the collections made by the Danish Expedition. Distribution: — Singapore (Elera), Mergui Isis. (v. Martens), Delta of the Irawady in Pegu (Blanford), Madras (Melvill & Standen, and others), Gulf of Manaar (Thurston), Bombay (Melvill aAhercrombie), Karachi (Melvill & Standen), Persian Gulf (v. Martens), Red Sea ? (P. Fischer). — Cochin China (L. Morlet), Ben-Son, Annam (Boutan), Canton (Jones & Preston), Hongkong (Mus. Zool. Univers. Haun.), Shanghai (Frauenfeld), Philippines (Elera), Borneo (Reeve), Auckland? (Frauenfeld). Chemnitz records his species M. Smaragdinus from Tranquebar and Guinea. Modiola Hanleyi, Dunk. Modioki Hanleyi, Dinkeu, Inde.\ molluscor. mar. Japonici, 1882, p. 223, pi. 16, figs. 3—4. — — — Martini u. Chkmnitz, Conchyl. Cabin., VIII Bd., 3 Abth., p. 95, pi. 20, figs. 4— 5. S. of Koh Chuen, 30 fathoms, shells (1). Koh Kahdat, 1 — 5 fathoms, sand with stones (3). Long. 9 — 49 mm. Distribution: — Singapore, shallow water (Sv. Gad). — Japan. Several of the specimens from the Gulf of Siam were hidden in their nests of byssus-threads. Modiola rhomboidea, Hani. Modiola rhomboidea, Hanley, Martini u. Chemnitz, Conchyl. Cabin., VIII, 3 Abth., p. 103, pi. 26, fig. 10. Gulf of Rayong, 7 — 10 fathoms, sand and mud (1). S. of Koh Samit, 20 fathoms, mud (2). Koh Chang, 3—5 fathoms, clay ('/a). W. of Koh Chang, 20 fathoms, mud (1). OtT Koh Kut, 5 fathoms (1). Long. 16—35 mm. Distribution:— Charbar and Gulf of Oman (Melvill & Standen). — China (Coll. Paetel), Japan (Dunker). Like many other jl/orf/o/a-species, the present species spins a kind of protecting nest of byssus- threads, which almost covers the animal. The specimens from the Gulf of Siam agree exactly with the figure in Martini u. Chemnitz; but I find that Reeve's figure and description (Conchol. icon., X, Modiola, Sp. 28) much more closely 35 131 resemble M. elongata, Sws,, lor instance; and his statement of "The Gambia, West Africa" as the locality, also makes it doubtful whether the species he describes and figures is the same as that recorded from the Asiatic waters. Both Reeve and Ci.KSSiN give ''Hanley, Species Recent Shells" as the place where the species was first described ; it is, however, not to be found there at all, and I have not suc- ceeded in discovering where Hanley's original description is to be found. Modiola elongata, Sws. Modiola elongata, Swainson, E.\otic Conchology. 1821, Part I. Second edit., 1841, p. 31, fig. 8. — — Reeve, Conchol. icon., X, Modiola, Sp. 4. — — — Martini u. Chemnitz, Concliyl. Cabin., VIII Bd., 3 Abtli., p. 97, pi. 27, figs. 1—2. N. of Koh Kahdat, 4—5 fathoms, coarse sand (2). W. of Koh Chuen, soft clay and mud ('/a). Long. 45 mm.* Distribution: — Moluccas, Aru Isl., Sorong (Tapparone Canefri), Jobi Is). (Geelwinck Bay). Modiola Metcalfei, Hani. Modiola Metcalfei, Hanley, Proc. Zool. Soc London, XII, 1844, p. 14. — — — Catalogue of recent bivalve shells, p. 235, pi. 24, fig. 25. — — — Reeve, Conchol. icon.. X, Modiola, Sp. 16. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 3 Abth., p. 116, pi. 32, ligs. 3—4. — — — L. MORLET, Journal de Conchyl., vol. 37, 1889, p. 161. Islands in the Gulf of Siam (L. Morlet). This species does not occur in the collections made by the Danish Expedition. Distribution: — Madras, Gulf of Manaar. — Philippines, China (Hongkong), Japan (Nagasaki), Malay Archip., Ratack Isis. (Marshall Isis.). Modiola plumescens, Dunk. (PI II, Figs. 13-14). Perna {Modiola; plumescens, Dinner, Museum Godeffroy, Catalog IV, 1868, p. 115. — V, 1874, p. 175 (no description). Modiola tumescens, Dunker, (Clessin) Martini u. Chemnitz, Conchyl. Cabin., VIII Bd., 3 Abth., p. 129, pi. 33, figs. 8-9. Common between Koh Kram and Koh Kut, 1 — 30 fathoms, sand and shells. Long. 3 — 30 mm. Distribution: — Viti and Samoa Isis. (Dunker), Java, Amboina and Banda (Ed. v. Martens in litt). I was at first of opinion, that the present species should most properly be referred to Mod. barbaia L., ' which it greatly resembles in form and colour; for instance, the epidermal prolongations in my specimens agree exactly with those ' Taken at Japan by tlie Challenger E.xpedition. 17* 132 36 of European specimens of Mod. burbata L. ; bul as the material at my disposal for comparison, was insufficient to decide this question, I sent some specimens to Pro- fessor Eu. V. Martens. He informed me that he considered them to be: "pluinescens, Dunker; Ci.essin beschreibt u. bildet sie ab, aber unter dem Namen tumescens, wahrscheinlich nur aus Irrthum (falsches Lesen)." The confusion introduced by Clessin into science by his "Monographs" in the new edition of Martini & Chemnitz: "Conchylien Cabinet" is much to be regretted. Edg. Smith mentions, in his report on "Alert's" zoological results, ' a Modiola sp. (taken at Port Molle) "remarkably like the European M.barbata" it is probably the present species. Modiola Philippinarum, Hani. Modiola Philippinarum, Hànley, Proc. Zool Soc. London, XII. 1844, p. 15. — — — Catalogue of rec. bivalve shells, p. 235, pi. 24, lig. 26. — — — Reeve, Conchol. icon., X, Modiola, Sp. 1. — — — RocHEBRUNE, Bull. dc la Soc. Philomath, de Pai'is, '^''/lo 1881 (Repr.), p. ü. — philippinarum, — Edg. Smith, Ann. and Mag. Nat. Hist., 7 Ser., XVlll, 1906, p. 254. Perna fulgida, H. Adams, Proc. Zool. Soc. London, 1870, p. 7, pi. 1, fig. 9. E. of Cape Liant, 9 fathoms, shells (1). Between Koh Rin and Cliff Rock, 15 fathoms (2), Koh Kram, 30 fathoms (I'/a). Long. 2—41 mm. Distribution: — Persian Gulf (Edg. Smith), Red Sea (Mac Andrew, Cooke). — Poulo Condor (Rochebrune), Philippines (Elera), China (Lischke), Japan (Stearns), - Amboina and Larentuka (v. Martens), Kei Randan (Tapparone-Canefri), Jobi Isl. (Geelwinck Bay)?, Torres Strait (Melvill & Standen), Mast Head Reef, Queensland (Hedley). Ed. v. Martens' supposes that Mod. Riimphii, Phil, is synonymous with M. Pbilippinariim, Hani. In the specimens from the Gulf of Siam the interior is whitely-iridescent. Modiola Evansi, Smith. Modiola evansi, Edg. Smith, Journ. of Concliology, X, 1903. p. 368. Tale Nawi in Lower Siam (Rich. Evans). This species does not occur in the collections made by the Danish Expedition. Edg. Smith says with regard to the locality from which this species has been taken : "This semi-lake is probably brackish water, being almost enclosed from the sea, and having several rivers and streams running into it." ' Report on the zoolog, collect, made in the Indo-Pacific Ocean during the voyage of H. M. S. "Alert", 1881-1882. Lond. 1884, p. 108. - With reference to L. v. Schrenck's statement concerning the occurrence of the species at North Japan, and its synonymy with M. modiolus L. cf. L. v. Schrenck, Molluslien d. Amur-Landes, p. 498, and C. E. Lischke, Japanische Meeres Conchjlien, I, p. 156. ' Rumphius Gedenkboek, 1902, Mollusken, p. 128 (20). 37 133 Modiola lignea, Reeve. Modiula liynea, Rekve, Conchol. icon., X, Modiola, Sp. 58, pi. X, fig. 71. _ _ _ Martini u. Chemnitz, Conc-liyl. Cabin., VIII, 3 Abtli., p. 102, pi. 27, lig. 3. S. of Koh Chuen, 30 fathoms, shells (2). Koh Kahdat, 1—5 fathoms, sand (1). Long. 15 — 20 mm. Distribution:— Gulf of Aden (Shopland), Red Sea (Sturany). — Torres Strait (Melvill & Standen), Australia (Clessin), Port Elizabeth (Sowerby). No locality was given for Reeve's original specimens in Cuming's collection; the species has since been found on the coasts of Australia and South Africa. It is also recorded from the West Indies, but this is undoubtedly due to erroneous determination. W. H. Dall states, in the report on the Mollusca of the Blake Expedition,' that he has specimens from the east and west coasts of Florida; and elsewhere- he states that it occurs along the east coast of America from S. Caro- lina to St. Thomas. I have in my collection, specimens from St. Thomas, collected by A. H. Ruse, and determined by Morch as M. lignea, Reeve; but the most im- portant distinguishing characters of this species — the well-marked and conspicuous lines of growth on the front and hinder parts, while the middle is smooth — do not occur at all in these specimens, which are perfectly smooth all over the valve; nor, in Dall's description of the Mollusca of the Blake Expedition are these cha- racters mentioned. The American specimens undoubtedly belong to another species. Modiola arcuatula, Hani. Modiola arcuatula, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 16. — — — Reeve, Conchol. icon., X, Modiola, Sp. 27, figs. 27 and 45. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 3 Abth., p. 101, pi. 30, figs. 8-9. — — — L. MoRLET, Journ. de Conchyl., vol. 37, 1889, p. 161. — — — P. Fischer, Catalogue d. Mollusques de I'lndo-Chine, p. 212. Siam (P. Fischer). Cambodge, at the exit of the river Kampong-Son (L. Morlet). This species does not occur in the collections made by the Danish Expedition. Distribution:— Singapore, Mergui Isis. — Cochin China, Japan, Philip- pines, Java. Modiola glaberrima, Dunk. Vulsella glaberrima, Dunker, Proc. Zool. Soc. London, XXIV, 1856, p. 363, No. 16. Modiola — — Reeve, Conchol. icon., X, Modiola, Sp. 48. — — — Martini u. Chemnitz, ConchyL Cabin., VIII, 3 Abth., p. 99, pi. 27, figs. 7— 8. — — — Edg. a. Smith, Report on the Lamellibranchiata of the Challenger E.\ped., p. 275. NW. of Koh Chang, 10 fathoms, mud (-/a). S. of Koh Chuen, 30 fathoms, shells (3). S. of Koh Samit, 20 fathoms, mud ('/a). Sound of Koh Chang, 3—5 ■ Report on the Mollusca. "Blake" E.xpedition, 1877-80, I, p. 236. Cambridge 1886. - W. H. Dall, Catalogue of the shell-bearing marine Mollusks and Bracliiopods of the south-eastern coast of the United States. Washington 1889, pp. 38-39. 134 38 falhonis, soll clay (1). W. of Koh Chang, 20 falhoms, clay (1). S. of Koh Kahdat, 8—10 fathoms, mud (2). W. of Koh Kiit, 30 falhoms, sand and mud (1). Long. 4—35 mm. Distribution: — Mergui Arcliip., Suez. — Canton, Easl Australia (the districts around Sydney). ' The specimens from the Gulf of Siam are all provided with a very shiny, greenish epidermis and several were either completely or partly hidden in their "nest" of byssus-threads, and fragments of shells, pebbles, etc. were partly attached to and partly entangled in these threads. Modiola perfragilis, Dunk.,- M. Japonica, Dunk., M.angusta, Cless.,' and M. cultelhis, Desh., ' are closely allied species. Pro- fessor Ed. v. Mautens, to whom I sent some specimens of the present species from Koh Samit, writes as follows: "Modiola perfragilis "Reeve" von d. Molukken ist wohl Jugendzustand von glaberrima." Brachyodontes (Hormomya) subramosus, Hanl. Modiola subramosa, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 14. — — — Catalogue of rec. bivalve shells, 1842—56, p. 241, pi. 24, fig. 30. — — — Rkkve, Conchol. icon., X, Modiola, Sp. 43. — — — Martini u. Chemnitz, Conehyl. Cabin., VIII, 3 Abtli., p. 121, pi. 31, fig. 11. — — — V. Martens, Süss- u. Brackwasser Moll. d. Ind. Archip., 1897, p. 226. — ramosa, Clessin, Martini u. Chemnitz, Conehyl. Cabin., Vlll, 3 Abtli., p. 134, pi. 26, fig. 8. West coast of Koh Chang, 1 fathom, old coral blocks (4). Koh Kahdat, 1 fathom, sand (1). Long. 7 mm. Distribution: — Mindanao and Samar, Philippines (Cuming and Jagor), Ternate, Moluccas (Dunker's collect.), Celebes (Pätel's collect.), the Gulf of Aniboina (RuMPH and v. Martens), Sorong (Tapparone Canefri), New Caledonia (Frauenfeld). According to v. Martens, ■' it is said to be able to live in brackish water and (in the Phillipines) perhaps even in freshwater. F. P. Marratt'^' records it (but this is surely an error) as obtained by the "Argo Expedition" at Abaco (Bahama Islands). Swainson's name Brachidontes, as a sub-genus of Modiola, was altered to Brachy- dontes by P. Fischer, and afterwards by Jukes-Browne' to the generic name Brachyodontes. ' E. V. Martens, Süss- u. Brackwasser Mollusken d. Indisch. Archipels, p. 87. - It is strange that Dunker iProc. Zool. Soc. Lend., 1856, p. 362) in his diagnosis of this species fi-om Cuming's collection says: "testa . . . parum splendida." Reeve, on the contrary, characterizes the same specimens as "shining" (nitente). ' Probabl}' identical with M. perfragilis, Dunk. ■" Magaz. de Zoologie éd. p. Guérin-Méneville, II, 1840, pl. 13, "from Kamtschatka" is undoubtedly synonymous with M. glaberrima, Dunk. 5 Loc. CiL p. 226. " HiGGiNS and Marratt, Mollusca of the Argo Expedition to the West Indies, 1876, Liverpool Museum Report, No. 1, 1878, p. 423. ' Proceed. Malacolog. Soc. London, vol. VI, 1905, pp. 221—23. 39 135 Brachyodontes emarginatus, Bens. (Reeve). Modiola emarginatus, Benson, M. S. in Mus. Cuming. — — — Reeve, Concliol. icon., X, Modiola, Sp. 60, pi. X, fig. 73. Perna emarginata, — Rochkbuune, Faune inalacol. de la Cochinchine et du Cambodge, Suppl., Bullet, de la Soc. philomath, de Paris, '"lu 1881, (Repr.) p. 4, No. 17. Modiola — — P. Fischer, Catal. d. Moll. de llndo-Chine, p. 212. — — — Martini u. Chemnitz, Conehyl. Cabin., VIII, 3 Abth., p. 114, pi. 20, fig. 3 (according to v. Martens not p. 120, pi. 25, figs. 7 — 8, these probably being M. Fortunei, Reeve). — — — V. Martens, Süss- u. Brackwasser Moll. d. Ind. Archipels, 1897, p. 227. Koh Kahdat, 1—5 fathoms, sand (3). Strand of Koh Kahdat (fragments). Long. 25 mm. Distribution: — The coast of Birma, in brackish water (Blanford), Bom- bay (Melvill & Abercrombie), Calcutta (v. Martens), Poulo Condor (Rochebrune), Philippines (Elera). Septifer bilocularis, L. Mytilus bilocularis, Linné, Systems Nat. ed. X, 1758, p. 705, No. 212. — ed. XII, p. 1156. — Mus. Ludov. Ulricæ, 1764, p. 540. Tichogonia — — Martini u. Chemnitz, Conchyl. Cabin., VllI Bd., 3 Abth., p. 10, pi. 2, figs. 11—17. Septifer — — Dunker, de Septiferis gen. Mytilaceorum et de Dreisseniis, 1855, p. 6. — — — Edg. a. Smith. Challenger E.xp. Lamellibranchiata, 1885, p. 271. — — — P. Fischer, Catal. d. Moll, de I'lndo Chine, p. 214. — — — Dautzenhkrg & Fischer, Journ. de Conchyl., vol. 53, 1905, p. 450. Mytilus Nicobaricus, Chemnitz, Conchyl. Cabin., Vlll, 1785, p. 155, pi. 82, figs. 736-37. — — — Reeve, Conchol. icon., X, Mytilus, Sp. 42. Very commonly distributed between Koh Kram and Koh Kut, 1 — 30 fathoms, sand, shells, mud and gravel; between old coral blocks. Long. 3—48 mm. Distribution: — Singapore, Strait of Malacca, Nicobars, Andamans, Aracan coast, Ceylon, Mahlos Atoll (Maldive Archip.), Persian Gulf, Red Sea, Seychelles, Amirautés, Madagascar, Mascarene Isis., Querimba Isis., Zanzibar, Mozambique, Natal. — Poulo Condor, China, Tonkin, Hongkong, Japan (Nagasaki), Philippines, Sumatra, Christmas Isl., Celebes, Sulu Isis., Moluccas, Sunda Isis., Aru Isl., Sorong, New Guinea, Salomo Isis., Torres Str., East Australia, New Caledonia, Marianne Isis., Viti Isis., Paumotu Isl. This species, which varies greatly, both in regard to colour and form, has presented to many authors the temptation of forming new species. Edg. Smith, in his report of the Lamellibranchiata of the Challenger Expedition (p. 271), has enumerated various synonyms, and undoubtedly some more maj' be added. Jukes- Browne' gives the gen. Septifer as a sub-genus of Brachyodontes. • Proc. Malacolog. Soc. London, vol. VI, 1905, p. 223. 136 40 Septifer excisus, Wiegni. Tichoyonia excisa, Wiegmann, Archiv f. Naturgeschichte, III, 1837, p. 49. — — — Mahtini u. Chemnitz, Conchyl. Cabin., VIII Bd., 3 Abth., p. 24. Septifer excisus, — Rkcluz, Revue et Magasin de Zoologie. 2 ser., I, 1849, p. 129. Mytilus — — Reeve, Conchol. icon., X, Mijtilus, Sp. 13. Septifer — — Crosse et Fischeh, Journ. de Conchyl., vol. 40, 1892, p. 75. — fuscus, RÉCI.UZ, Revue (et Magasin) de Zoologie, 1848, p. 279. — 1849, p. 128. Koh Lom, W. of Koh Chang (2). West Coast of Cambodge in the Gulf of Siam (Pavie). Long. 21 — 26 mm. Distribution: — Mergui Isl., Karachi, Gulf of Aden, Red Sea (pleistocene), Mauritius, Madagascar, Mozambique, Querimba Isis. — Funafuti (Ellice Isl.). Tichogonia (Septifer) siamensis, Clessin' from "Siam," and also Septifer Troscheli, Dkr.,^' undoubtedly belong to the present species. Clessin^ knows Septifer excisiis, Wiegm. only from Dunker's description, and has hardly any clear conception of it; neither has he examined Reeve's figure, as he writes: "Reeve hat die Art nicht abgebildet, trotzdem sich dieselbe in der Cuming'schen Sammlung befinden muss." Lithodomus gracilis, Phil. Modiolu {Lithophagiis) gracilis, Pmi.ii'ri, Zeitschr. f. Malakozool., 1847, IV, p. 117. — gracilis, Phimppi, Abbild, u. Beschreib, neuer od. wenig gek. Conchyl., 1851, III, p. ö (19), pl. II, flg. 1. Lithodomus gracilis, Phii.ippi, Reeve, Conchol. icon., X, Lithodomus, Sp. 4. — _ _ p. Fischer, Catal. d. moll. de llndo-Chine, p. 213. Lithophaga — — Dunker in Martini u. Chemnitz, Conchyl, Cabin., 1882, VIII, 3 Abth., p. 12, pi. 4, figs. 7-8. North end of Koh Chang, 1 — 12 fathoms, old coral blocks (many specimens). Koh Kahdat, 1 fathom, sand (9). Long. 11 — 72 mm. Distribution: — Malacca, Mergui Isis., Madras, Ceylon, Mahlos-Atoll (Maldive Archipel.), Red Sea, Seychelles,* Amirautés, Tschago's Isis., Mauritius, Bourbon, Querimba Isis., Zanzibar. — Poulo Condor, China (Shanghai), Sunda Isis. (Java, Flores, and others), Amboina, Sorong, Torres Strait, north-west Australia, Tahiti. With regard to the three closely allied forms — L. teres, Phil., L. gracilis, Phil., and L. niger, d'Orb. — I do not doubt, judging from the material at hand, that L. teres, Phil., is identical with L. gracilis, Phil. E. v. Martens has already stated in "Die Mollusken d. Maskarenen u. Seychellen," (p. 143) that L. teres, Phil., cannot be separated as a species from L. (gracilis, Phil. (Chemnitz's figure'' of Mytilus litho- 1 Martini u. Chemnitz, Conchyl. Cabinet, Vlll, 3 Aljth., pp. 19—20, pl. 15, figs. 8—9. - W. Dunker, Neue Mytilaeeen, Zeitschr. f. Malakozool., X. 1853, p. 87. ' loc. cit., pp. 24-25. * Ph. Dautzenrerii records it (Bull, de la Soc. Zool. de France, 1893) from here, and says: "Litho- domus gracilis Philippi, indiqué par von Martens sous le nom de L. teres Philippi." •■ Chemnitz, Conchyl. Cabinet, VIII, 1785, pl. 82, fig. 729. 41 137 phagiis" from St. Maurice and Bourbon agrees exactly with L. gracilis, Phil., but yet Phu.iimm and Dunkeh refer it to L. teres, Phil.). Dunkeu' thinks that L. teres is closely analogous to L. niger, d'Orb. (= L. Antillarum, Phil.), and is perhaps only a variety of the same. The reason for this must be sought in the opinion expressed in his diagnosis of L. teres, Phil.: "epidermis nigro-castanea, in dorso ct subler umbonibus laevis, in latere ventris simili modo striata ac in Lithophaga nigra." The most important mark of distinction between the West Indian L. niger, d'Orb., and the East Indian L. gracilis, Phil., is, as far as I can see from the material at my disposal, precisely this epidermal striation. In L. gracilis, Phil., these trans- verse lines extend almost to the anterior end (diminishing gradually in size) and only a small portion of the outermost part of that end is quite smooth; in the posterior part, the striation is usually continued somewhat farther than in L. niger. On comparing two specimens — one of each of these species — of equal size (e.g. 49 mm.), the result will be as follows: in L. niger (from St. Thomas) the striation is continued bej'ond 32 mm., as measured along the lower margin of the shell, while in L. gracilis (from the Gulf of Siam) it covers 40 mm. Lithodomus straminea, Dunker. Lithodomus stramineiis, Dunrer, Reeve, Conchol. icon, X, Lithodomus, Sp. 11. Lithophaga straminea, — Dunker in Martini u. Cmkmnitz, Conchyl. Cabin., VIII, .'i Abth. A, p. fi, pi. 2, figs. 1—2. Koh Chang, very low tide (1). Long. 22 mm. Distribution:— Madras (Melvill & Standen), the Gulf of Manaar (Thurston). — Mast Head Reef, Queensland (Heoeev). The habitat "West Indies" given in Cuming's collection, is undoubtedly due to an error. J. Marille and G. le Mesle record" Lithodomus lithophagiis L. from Poulo Condor; Crosse^ is right in doubting the correctness of this determination. Is it not more probably L. straminea, Dkr., that has been found? Lithodomus Malaccana, Reeve. Lithodomus Malaccana, Reeve, Conchol. icon., 1858, X, Lithodomus, Sp. 20. Lillxoplutga Malaccana, — Martini u. Chemnitz, Conchyl. Cabin., VIII, 3 Abth. A, p. 2(», pi. \, fig. 1. Litlwdomiis sabula, — Conchol. icon., X, Lithodomus, Sp. 26. Lithophaga — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 3 Abth. A, p. 21, pi. V, fig. 13 (figs. 11 — 12?). — cavernosa. Dunker, Martini u. Chemnitz, Ioc cit., p. 7, pi. II, figs. 5— 6; pi. V, figs. 15— Hi. — reticulata, — — Ioc. cit., p. 19, pi. V, figs. 9- 10. ' Martini u. Chemnitz, Conchyl. Cabin., VIII IJd., 3. Abth., p. 13. ■î Journal de Conchyl., XIV, 18(i6, p. 118, ä Ioc. cit. p. 119. 1). K. L). Vi.lcnsk. Selsk. Skr., 7. Ra-klie, nalurvidensk, :>]i mnllu-m. AM V. 3. 18 138 42 Several specimens were taken between Cape Liant and Koh Kahdat in 1 — 15 fathoms, boring in old coral blocks, and from sandy bottom. Young specimens were taken from mud and stony bottom. Long. 6—26 mm. Distribution: — Malacca, Mergui Archip., the Gulf of Manaar (Thurston), Karachi? (Mklvill & Standen), Persian Gulf (Annandai.e), Hulule Isl. (Edg. Smith), Zanzibar and Aldabra Isl. (Voeltzkow). — Philippines, New Guinea, Cape York, North Australia ("Challencer"), New Caledonia, Tahiti. The present species, like all boring Molluscs, is subject to great variation in regard to form; I have put L. subula, Reeve, and Bunker's L. cavernosa and reti- culata as synonymous forms, and several more could no doubt be added. Cm. Hedley' supposes that L. levigata, Q. and G. ^ is the same species as L. Malaccana, Reeve; should this prove to be the case. Reeve's name for it must yield to that of QuoY and Gaimard, which has the priority. Besides boring holes in coral blocks, shells, and similar objects, this species often makes free "chalk houses," there is, for instance, a specimen of Chama multisquamosa, Reeve from Koh Kahdat, in one of the valves of which two individuals of L. Malaccana have made their two "houses" side by side; these are smooth interiorly, agreeing exactly in form with that of the Lithodomus-\al\'e, and their only communication with the outer world is through an oblong hole bored in the valve of the Chama. Lithodomus (Botula) cinnamomea, Chemn. Mgtilus cinnamominus, Chemnitz, Conchyl. Cabin., VIII, 178,5, p. 152, pi. 82, fig. 731. Modiola cinnamomea, Lamauck, Encyclop. method., pi. 221, fig. 4. Lithodomus cinnamominus, Chemnitz, Reeve, Conchol. icon., X, Lithodomus, Sp. 5. — cinnamomeus, — Fischer, Catal. d. Moll, de I'lndo-Chine, p. 213. Mytilus fuscus, Gmelin, Syst. Nat., ed. XIII, p. 3359, No. 35. Lithophaga fiisca, Gmelin, Mahtini u. Chemnitz, Conchyl. Cabin., VIII Bd. 3 Abtli., \>. 25, pi. 6, figs. 8 — Î). Modiola silicula, Lamarck, Anira. s. vert. Vll, 1836. p. 25, No. 19. Common from Cape Liant to Koh Chang, 1 — 30 fathoms, in old coral blocks, on stony and shelly bottom. Long. 2—28 mm. Distribution:— Mergui Archip., Nicobars, Ceylon, Suvadiva Atoll (Maldive Archip.), Karachi, Red Sea, the Gulf of Aden, east coast of Africa, Seychelles, Mau- ritius, Bourbon. — Poulo Condor, Annam, Philippines, Torres Strait, Mast Head Reef (Queensland), north-west Australia, New Caledonia, Paumotu Isl. — East coast of America from Cape Fear to Guadaloupe. I agree entirely with Crosse and Fischer when they-^ write concerning Chemnitz's species from the Nicobars: "Est-il réellement identique à la forme analogue des Antilles?" The material at my disposal unfortunately is not con- ' Australian Museum, Sydney, Memoir III, 1896 — 1900, p. 492. - Voyage de l'Astrolabe, III, p. 464, pi. 78, figs. 17 — 18. " Journal de Concliyliologie, XXXVII, 1889, p. 291. 43 139 siderable enough lo decide Ihe question. — The specimens from the Gulf of Siam, which agree most closely with the form figured by Reeve in PI. I, Fig. 5 b, have all a dark-brown epidermis and strongly marked, broad, step-like zones of growth. Also forms like Lamarck's Mod. silicula occur frequently. Modiolaria Cumingiana, Dunker (Reeve). Modiola Cumingiana, Dlnkeu, MS. Mus. Cuming. — — — Reeve, Conchol. icon., X, IS.'iV, MorfioZa, Sp. 50. Modiolaria — — Martini u. Chemnitz, Conchy]. Cabin., VIII, 3 Abtii., p. 14(i, pi. :U, figs. 2 — 3. — cumingiana. — Edg. Smith, Report Challenger E.xped. Lamellibianchiata, I.S.S."), p. 278. Koh Kram, 20 fathoms (Va). Between Koh Riot and Koh Mesan, 3—5 fathoms, sand (1). Long. 8—11 mm. Distribution:— Karachi (Melvill & Stanben), Gulf of Aden (Shopland), Red Sea (Stcrany), Mauritius (Liénahd), Natal (Edg. Smith). — Japan (Dunker and Stearns). Along the north (Torres Strait, and several other places), east (Moreton Bay, Sydney, and several other places), south (St. Vincent's Gulf, and several other places) and west coast (Swan River, and several other places) of Australia. Tasmania (Tate and May). Modiolaria cuneata, Gould. Modiolaria cuneata, Gould, Proceed, of the Boston Soc. of Nat. Hist., VIII, 1861 — 62, p. 38. — — — Edg. Smith, Laniellibranchiata of the Challenger Exped., p. 278. pi. 16, tig. 7. — — — Pritchard and Gatliff, Proceed. Roy. Soc. Victoria, vol. 17, pt. 1, 11)04, p. 204. Koh Kahdat, 1—2 fathoms (1). Long. 4 mm. Distribution:— Port Jackson, Sydney ("Challenger"), False Bay, Cape of Good Hope (Gould). "Common Port Phillip, associated with tunicates, Carrum to Frankston, Portsea" (Pritchard and Gatliff). Mod. coenobita, Vaillant, from Suez, ' is closely allied to this species. Modiolaria nana, Dunk. (PI. 11, Fig. 15). Lanistina nana, Dunker, Proc. Zool. Soc. London, XXIV, 1856, p. 365. Modiola — — Reeve, Conchol. icon., X, Modiola, Sp. 56, pl. X, fig. 6!). Crenella — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., VIII, 3 Abth., p. 152, pl. 34, fig. 10. ' Journ. de Conchyl., vol. 13, 1865, pp. 122—123, Savignv, Descript. de l'Egypte. Coquilles, pl. XI, tig. :i. A. H. Cooke (Ann. and Mag. Nat. Hist., Ser. 5, vol. 17, p. 141) considers it to he identical with Mod. marmorata, Forb. Edg. Smith (Proc. Zool. Soc. London, IS'Jl, pp. 393-94) thinks, however, that Cooke is wrong in this. Sowerby (Marine shells of South Africa, p. 65) has specimens from Port Elizabeth. 18* 140 44 Gulf of Rayong, 7 — 10 fathoms, mud ('/s). Koh Kram, 30 fathoms ('/-■). Between Koh Mesan and Cape Liant, 5 — 9 fathoms (^/a). Koh Kalidal, 1—5 fathoms, sand (-/j). Long. 4 — 13 mm. Distribution: — Port Lincoln, South Australia (Cuming), Sullivan Isl., Mergui Archip. (v. Martens). Dunker and Reeve give the size of the specimens in Cuming's collection as 4 mm.; from the Gulf of Siam there are specimens measuring as much as 13 mm. Reeve's figure (very badly reproduced in Clessin's Monograph in "Martini & Chemnitz") is not good in all points, hence I have given a new figure here. As all the specimens from the Gulf of Siam were taken dead, I have not been able to verify Dunker's statement: "Pagina interna margaritacea." Modiolaria miranda, Edg. Smith. Modiolaria miranda, Edg. Smith, Rep. Zoolog. Collect, made during the voyage of H. M. S. "Alert." 1884, p. 1(»8. pi. 7, fig. N. Common (from 16 different localities) between Koh Rin and Koh Kut, 1 — 30 fathoms, stones, shells, gravel and mud. Long. 1 — 7 mm. Distribution: — Dundas Straits. Some of the specimens were taken from among the spines of Slephanocidaris bispinosa, Lam., from a depth of 30 fathoms. Modiolaria (Gregariella) opifex, Philippi (non Say). Modiola opifex (Say'?), PiiiLiri'i, Abbild, u. Beschreib, neuer od. wenig gekannt. Conchyl., Ill, 1851, Modiola, p.21 (7), pl. 11, fig. 7. — — Say, Reeve, Conchol. icon., X, Modiola, Sp. 39. Lilhophaga opifex, Say, Dunkeu in Martini u. Chemnitz, Conchj'l. Cabin., VIII, 3 .'\btli. ,\, p. 211, pl. (j, flg. l(i. Litliodomus splendidus, Reeve (non Dunker), Reeve, Conchol. icon., X. Lithodoimis, Sp. 31. Between Koh Mesan and Koh Chuen, 25—38 fathoms, stones (7). Between Koh Mesan and Cape Liant, 5—9 fathoms (''l). Long. 9—15 mm. Distribution: — Sydney (Cuming). — Brazil (Henr. Krover; Desterro, Fr. Müller; Rio Janeiro, Cuming). In all the specimens from the Gulf of Siam the most posterior, flattened part of the valves, limited by ridges set with stiff epidermal bristles, was covered with adherent grains of sand; this gives the animals, which live buried in the sand, a great resemblance to their surroundings. Modiola difficilis, Deshayes, ' appears to me to resemble more particularly a worn specimen of the present species. > Mollusques de I'ile de la Reunion (Bourbon), 18()3, p. 23, pl. 3, figs. 22—24, 45 141 Modiolaria (Gregariella) coralliophaga, (Chemn.) Gmel. Mißihts corallioplmgus, Chemnitz, Concbyl. Cabin., VIII, 17S.'), p. 174, pi. 84, fig. 752. — — — Gmelin, Syst. Nat., ed. XIII, 1790, p. 3359, No. 31. Modiola semen, Lamarck, Anim. s. vert., éd. 2, VII, 183(i, p. 2(), No. 21. — opifex, Say (non Phii.ippi), Journ. Acad. Nat. Se-., Philadelphia, IV, 1825, p. 3()8, pi. 19, lig. 2. — — — Vekhill & Busch, Trans. Connecticut Acad. X, 1900, p. 516, pi. 58, fig. 3. — divaricata, Philiwm, Zeitschr. f. Malakozool., 1847, p. 115. — — — Abbild, u. Beschreib, neuer od. wen. gek. Conchyl. Modiola, p. 21 (7), pl. II flg. 8. LilliiMlunuis (lioaricatus, Philippi, Reeve, Conchol. icon., X, Lithodomus, pl. V, Sp. 34. Lilhophaga divaricata, Philippi, Mahtini u. Chemnitz, Conchyl. Cabin.. VIII Bd. 3 Abth. A, p. 2U. Modiolaria - — Lischke, Japanische Meeres Conchyl., II, p. 148. At the north end of Koh Chang, 1 — 12 fathoms, in old coral blocks (6). Long. 7 — 13 mm. Distribution: — Japan, Nagasaki (Lischke). — East coast of America from Cape Hatteras and the "Lesser Antilles" to Rio Grande do Sul. The specimens from the Gulf of Siam agree in all points with the specimens from the West Indies. Fam. Pteriidae. Pteria spectrum, Reeve. Avicula spectrum, Reeve, Conchol. icon, X, 1857, Avicula, Sp. 59. — — — Dunker in Martini u. Chemnitz, Conchyl. Cabin., VII, 3 Abtli., 1872, p. 49, pl. 17, fig. 1. Koh Chuen, 30 fathoms (1). Long. 22 mm., alt. 11 mm. Distribution: — Philippines. I have compared the small specimen from Koh Chuen with Reeve's original specimen in the British Museum, and although somewhat different I cannot see that it can be referred to any other species than to P. spectrum, Reeve. Pteria serrulata, Dunk. Aoictda serrulata, Dunker, Zeitschr. f. Malakozoologie, V, 1848, p. 178. — — — Martini u. Chemnitz, Conchyl. Cabin., VII Bd. 3 Abtli., p. 18, ])1. 5, figs. 1—2. — lata, Reeve, Conchol. icon., X, Avicula, Sp. 5. Between Koh Mesan and Cape Liant, 5—9 fathoms (1). Long. 32 mm., alt. 24 mm. Distribution: — Moluccas, Torres Strait. Professor Ed. v. Martens, to whom I sent the specimen for comparison, writes to me as follows: "wahrscheinlich lata Reeve, nur die Form des Ohrs passt nicht recht." 142 46 Pteria (Electroma) zebra, Reeve. (I'l. II. Figs. ll)-18). Ai'icula zebra, Rkeve, Concliol. icon., X, Avicula, Sp. 36. — — — iM,vnTiNi u. CHKMNn/,, Concliyl. Cabin.. VII, ;i Aljtii., p. liO, pi. '21, lig. 3. Koh Kram, 30 fathoms (2). Koh Mesan, 15 fathoms, stones (2). Between Koh Mesan and Koh Cliuen, 25—38 fathoms, stones (6). Long. 3 — 12 mm. Distribution: — N. Male Atoll (Edg. Smith). — Gulf of Manaar (Standen & Lkicester), Tulicorin (Thurston), Port Elizabeth (Sowerby), Port Denison, Queens- land ("Alert"), Moreton Bay, Australia (Cuming), King Island, Tasmania (Tate & May). A variety, with twelve pale-brown lines radiating from the umbo, (without the characteristic oblique lines) was taken, to the number of three specimens in 30 fathoms at Koh Cliuen; it was not found attached to any object as was the type form. — The specimens, from the localities mentioned above, were all found attached to Plumiilaria sp. As may be seen from the figures in PI. II, Figs. IG — 18, the mimicry is exceedingly striking; the beautiful colour-ornamentation upon the valves resembles exactly the branches of the Hydroid. Reeve describes and figures it as attached to a Sertularia. Thurston' also mentions its mimicry in relation to Aglaophenia urens upon which it settles. G. J. Allman mentions in the Report on the Hydroids of the Challenger Expedition,- when treating of Plumiilaria abieiina, that "The specimen had numerous individuals of an Avicula-like fry adhering to it." Judging from the figure it can, however, scarcely be A. zebra, Reeve. Pteria pulchella. Reeve. Avicula pulchella, Reeve, Conehol. icon., X, 1857, Avicula, Sp. 22. — — — Martini u. Chemnitz, Cunchyl. Cabin., VII Bd. 3 Abth., p. 42, pi. 13, fig. (i. East of Cape Liant, 9 fathoms, shells (1). Long. 20 mm., alt. 16 mm. Distribution: — Philippines, East and South Australia. On account of the small size of the specimen, there may perhaps be a slight doubt concerning the correctness of the determination. Pteria (Margaritifera) vulgaris, Sebum. I'erlatnalcr inilgaris, Schumacher, Essai d'un nouv. syst. d. habitat, d. vers test., 1817, p. 1U8. pi. 2U, lig. 3. Margaritifera — — Jameson, Proc.Zool.Soc-. Lond., 1901, I, p. 384, Sp. 13. — — — W. A. Herdman, Report on the Pearl Oj'ster Fisheries of the Gulf of Manaar, II, 1904, pp. 37— 76, pi. 1-9. Avicula fitcala, Gould, Proc. of the Boston Soc. of Nat. Hist., Ill, 18ÖU, p. 309. — — - Un. St. Expl. Exped. Moll., p. 441, pi. 39, fig. 551. — — — Reeve, Conchol. icon., X, .4(>ioi!/a, Sp. 74 (pi. XVII). ' Madras Government Museum, Bulletin No. 3, Ràmésvaiam island and Fauna of the Gulf of Manaar, 2 ed., Madras 1895, p. 130. - Zoology, vol.7, 1883, p. 21, pi. 3. The specimen was from Prince Edward's Island, 150 fathoms ('?). 47 143 Commonly distributed between Koh Rin and Koh Kong. 1 30 fathoms, mud, sand, gravel, shells and stones. The specimens gathered were almost all young individuals. Long. 10—38 mm., alt. 10—32 mm. Distribution: — Malacca, Singapore, Madras, Ceylon, Palk's Strait, Gulf of Manaar, ' Maldives, Persian Gulf, Gulf of Aden, Red Sea, Suez (since the opening of the Suez Canal this species has wandered into the Mediterranean. There are typical examples from Alexandria and Malta in the British Museum.-), Mauritius, Bazaruto Isl., Durban. — Philippines, Japan ('?), Flores, Sandwich Isis., Torres Strait, North Australia, East Australia (as far as Sydney), West Australia (as far as Sharks Bay), New Guinea, New Zealand (Gould). I have followed H. L. Jameson (1. c.) in his opinion regarding P. vulgaris, Schum., although I feel convinced that several of the species in his "Section c" are nothing else but varieties of this species. Schumacher's original specimen is in the Zoological Museum of the University of Copenhagen, and I can only confirm Jameson's opinion that P. vulgaris, Schum., is identical with P. fucaia, Gould. P. vulgaris, Schum., has had numerous names given to it, owing to its variability in shape and colour. Thus A. H. Cooke ^ enumerates the following of Reeve's species as identical (the original specimens in the 'British Museum" were at his disposal): — imbricata, muricata, lentiginosa, occa, fimbriata, anomioides, aerata, irradians, and nebulosa, Conr. Jameson (who has had the same specimens for examination) gives: — occa, Reeve, aerata, Reeve, perviridis. Reeve, varia, Dunker, and badia, Dunker, as synonyms of P. vulgaris, Schum. G. B. Sowerry^ believes that Avicula flabellum. Reeve,'' and A. lacunata, Reeve, may be added to these. A. Martensi, Dunker,'' is also, no doubt, nothing but a form of the present species. G. F. Angas ' considers A. placunoides, Reeve, a variety of fimbriata, Reeve. ' For details comp. L. G. Seurat, l'Huître perlière. Paris 19Ü1. — E. Im Thurn, Sketch of tlie Ceylon Pearl Fishery of 1903. (Spolia Cej'lanica, I. Colombo 1U03). — J. Hohnei.i., The Biolog. Results of the Cej'lon Pearl Fisherj' of 1!)Ü4. (Reports from the Ceylon Marine Biological Laboratory No. 1, Colombo 190.'). — J. Caixott Gaskin (Proc. Zool. Soe. London, 190(i, p. 803), A Memorandum on the Pearl- shells in the Persian Gulf. — Edg. Thursto.n, Notes on the Pearl and Chank Fisheries and Marine Fauna of the Gulf of Manaar, Madras 1890. — Report on the Pearl Oyster Fisheries of the Gulf of Manaar, by W. A. Heruman. 1— ö. London 1903 — 6. — P. vulgaris, Schum., is fished here on a large scale for the sake of the pearls. - H. L. Jameson (1. c. p. 385) and Vassel, Sur la Pintadine du Golfe de Gabes (Comptes-rendus. Assoc, franc, p. l'avancera, d. sc, 189(5, pp. 4ô8— (Ki). ^ The Annals and Magaz. of Nat. Hist., vol. XVII, 1886, pp. 130—37. ■* Appendix to Mai'ine shells of South Africa, Lond. 1897, p. 27. ^ This is a form from Venezuela and A. H. Cooke says (1. c. p. 137| that the type in the British Museum differs from A. fucata, Gould. * Index raolluscor. mar. Japon. Cassel 1882, p. 229, pi. 10, figs. 7—8. ' Proc. Zool. Soc. London, 18(!7, p. 930. 144 48 Pteria (Margaritifera) vulgaris, Schuin. var. occa, Reeve. Avicula occa, Rf.kvk, Concliol. icon., X, 18.')7, Avicula, Sp. 24. — {Meleugrina) occa, Reeve, Mahtini u. Chemnitz, Conchyl. Cabin., Vll Bd. ;i Abtii., p. 42, pi. 13, fig. 5. Koh Kram, 30 fathoms ('/a). Long. 28 mm., alt. 29 mm. Distribution: — Red Sea, Gulf of Aden (Joussiîaumi:). Professor Ed. v. Martens, to whom I sent the specimen for comparison, writes to me as follows: "vermuthlich occa Reeve, wenn man annehmen kann, dass bei der llirigen die Schuppen abgerieben seien." A.H.Cooke' and H. L. Jameson^ are certainly right in considering A. occa, Reeve, a form of Marg. vulgaris, Schum. (= A. fiicata, Gould).'' The present species has probably a far wider distribution than that stated above, but to ascertain this, further investigations will be necessary. A. GiAHD* has collected what he believes to be its synonyms, and according to these its geographical distribution becomes considerably wider. Pteria (Margaritifera) nigra, Gould. Avicula nigra, Gould, Proc. of tlie Boston Soc. of Nat. Hist., vol. 3, 1850, p. 309. — — — Un. St. Expl. E.\ped. Moll., p. 438, pi. 40, fig. 4.'-.4. — tristis, Dunker, Martini u. Chemnitz, Conchyl. Cabin., VII, 3 Abtli., p. 44. pi. 14, fig. 3. East of Koh Chuen, 9 — 10 fathoms, shells. Long. 48 mm., alt. 38 mm. Distribution: — Singapore. A smaller specimen (long. 19 mm., alt. 16 mm.), which, with some doubt, I refer to the present species, was taken at Koh Kahdat in one fathom, on a sandy bottom. Pteria (Margaritifera) citrina, Dunk. Avicula (Meleagrina) citrina, Dunkek, Zeitschr. f. Malakozoologie, IX, 18r)2, p. 78. — — — — Martini u. Chemnitz, Conchyl., Cabin., VII I5d. 3 Abth., pp. 14 and 71, pi. 3, fig. 4, and pi. 25, fig. 1. Pteria {Margaritifera) — — Jameson, Proc. Zool. Soc. London, 1!)01, p. 383. Strand of Koh Kahdat ('/s). Long. 24 mm., alt. 2.5 mm. Distribution: — Dutch India (E. v. Martens in litt.). ' Annals and Magaz. Nat. Hist., Ser. 5, vol. 17, pp. 136—37. -' Proc. Zool. Soc. London, 1901, p. 384. ' A. Pagenstecher describes various forms of P. occa, Reeve, from the Red Sea in "Ueber die v. R. Kossmann am Rothen Meere gesaram. Mollusken," 1877, p. 35. ^ Comptes rendus hebdomad, d. seances de la Soc. de Biologie, Paris, Tome 56, 1004, pp. 255 — 57. 49 145 Malleus figuratus, Chemn. Ostrca figurata. Chemnitz (Anas domestica Speiigleri), Concliyl. Cabin., VIII, 1785, p. 17, pi. 70, fig. G58 ; pi. 71, fig. 659. — analina, Gsielin, S3-st. Nat, ed. Xlll, p. 3333, No. 101. Malleus anatinus, Lamarck, Anim. s. vert, éd. 2, Vil, p. 93. — — — Reeve, Conchol. icon., XI, Malleus, Sp. 3. — — Gmelin, Martini u. Chemnitz, Conchyl. Cal)in., VIII, 1 Abth , p. 8, pi. 2, fig. 4, and pi. 3, fig. 1. — — — P. Fischer, Catal. d. Moll, de Ilndo-Chine, p. 210. Koh Kram, 30 fathoms (1 specimen, long. 3 mm.). E. of Cape Liant, 9 fathoms, shells (1). The northern side of Koh Mesan, 10—15 fathoms, stones (3). Between Koh Mesan and Koh Chuen, 25—38 fathoms, stones with shells (1 specimen, long. 7 mm.). Long. 3 — 16 mm., alt. 5 53 mm. Distrihution: — Nicobars, Kolumadulu Atoll (Maldive Archip.). Poulo Condor, Java, Timor, Moluccas. Malleus albus (Chemn.), Lam. Oslrea Malleus albus, Chemnitz, Conchyl. Cabin., XI, 1795, p. 257, pi. 20G, fig-s. 2029-30. Malleus albus, Lamarck, Hist. nat. d. anira. s. vert, VI, 1819, p. 144, No. 1. — 2 éd., VII, p. 91, No. 1. — — — Reeve, Conchol. icon., XI, Malleus, Sp. 1. — — — Martini u. Chemnitz, Concliyl. Cabin., VIII, 1 Abth., p. 4, pi. 1, figs. 1—2. — — — Crosse & Fischer, .lourn. de Conchyl., vol. 40, 1892, p. 75. — — - Pritchard & Gatliff, Proc. Roy. Soc. Victoria, vol.17, pi. 1, p. 258. Between Koh Rin and Cliff Rock, 15 fathoms (2). Koh Chuen, 30 fathoms (1). S. of Koh Kahdat, 8—10 fathoms, mud (Vs). Gulf of Siam, west coast of Cambodge (Crosse & Fischer). Alt. 2—58 mm. Distribution:— Singapore, Ceylon, Gulf of Aden. — Philippines, China, Japan; north, east, and south coast of Australia. Malleus régula, Forsk. Oslrcii rcfjula. Forsk.u-, Descript. animal, quae in itinere orient, observ., 1775. p. 124. Malleus - Savigny, Descript de l'Egypte. Coquilles, pi. 13, figs. 1—4. — Reeve, Conchol. icon., XI, Malleus, Sp. 4. — — — Pagenstecher, Ueber die von Kossmann am Rothen Meere gesamm. Mollusken, 1877, p. 31, pi. 1, figs. 17-19. — — — Issel, Malacol. d. Mar Rosso, 1869, p. 97. Ostrea Vulsella, Chemnitz, Conchyl. Cabin., VIII, 178.5. p. 15, pi. 70, fig. 657. — Gmelin, Syst. Nat , ed. XIII, p. 3333, No. 100. Malleus I'ulsellaliis, Lamarck, Anim. s. vert, cd. 2, VII, p. 92. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 1 Abth., p. 7, pi. 2, fig. 3. var. decurtatus, Lam. Malleus Jecui talus, Lamarck, Anim. s. vert, éd. 2, VII, p. 93. — Reeve, Conchol. icon., XI, Malleus, Sp. 10. — - — A. H.Cooke, Ann. & Mag. Nat Hist, Ser. 5, vol. 17, 1886, p. 137. — tigrinus, Reeve, Conchol. icon., XI, Malleus, Sp. 7. II. K. I). VlilcnsU..Sclsk. Skr., 7. R:L.Uke, naliiivUlcnsk. ng matlicm. AW. V. 3. 19 146 50 E. of Kolî Chuen, 9 — 10 fathoms, shells (1). Koh Kahdat, 1 fathom, sand (1 abnormal specimen). Koh Kram, 30 fathoms (1 specimen, alt. 11 ram.). Long. 19 mm., alt. 31 mm. Distribution; — Persian Gulf, Gulf of Aden, Red Sea, Suez, Ascension Isl. (Edg. a. Smith). — Philippines, Japan, Timor, Moluccas; North-west and South Australia. The specimen from Koh Chuen belongs to var. decurtntits, Lam., while the specimens from Koh Kahdat and Koh Kram must be referred more especially to M. régula, Forsk. A single valve (long. 13 mm., alt. 15 mm.) was taken between Koh Kut and Koh Kahdat (in about 10 fathoms, on a shelly bottom); this must undoubtedly be referred to var. deciirtatus. Lam. Perna vespertilio, Reeve. Perna vespertilio, Reeve, Conchol. icon., XI, Perna, Sp. 26. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 1 Abtli., p. 37, pi. 13, fig. 2. Koh Kram, 30 fathoms (1/2). Long. 53 mm., alt. 55 mm. Distribution: — Philippines. As far as I can judge from the scanty material at my disposal, this species varies exceedingly, and if a number of specimens could be obtained for comparison from the same district, several forms, which are now regarded as distinct species, would undoubtedly be reduced to synonyms; indeed perhaps it would be necessary to refer the whole "species" to another form. Perna Spengleri, Chemn. Siliqua Spengleri, Chemnitz, Conchyl. Cabin., VII, 1784, p. 250, pi. 59, fig. 578. Ostrea Legumen, Gmelin, Syst. Nat., ed. XIII, p. 3339, No. 128. Perna dactylus, Valenciennes, Encycl. method., pi. 175, figs. 2—3. — legumen, Gmelin, Reeve, Conchol. icon., XI, Perna, Sp. 22. — linguaeformis, — — — Sp. 7. — laticostata, — — — Sp. 9. — candata, — — — Sp. 5. - Reeve, A. H. Cooke, Ann. & Mag. Nat. Hist., XVII, 5 Ser., 1886, p. 138. Common at Koh Chang, Koh Lom and Koh Kahdat, 1 — 12 fathoms, sand and old coral blocks. Long. 4—12, alt. 5—26 mm. Distribution:— Mergui Archip., Nicobars, Red Sea, Lifu Isis., Society Isis. I have i-e-introduced Chemnitz's name, which, strangely enough, in spite of its priority, has hitherto been disregarded. The original specimen figured by Chemnitz (besides a smaller one from Spengler's collection), is in the Zoological Museum of the University of Copenhagen. It is somewhat worn and deformed, but nevertheless agrees entirely with Gmehn's P. legumen. The deep-blue spots at the beaks men- tioned by Chemnitz, are due to the fact, that the valves of his specimen, when 51 147 young, were diuk-coloured, quite an individual character. In the new edition of "Mautini & Cm.MNiTz, Conchy]. Cabinet, " Clessin has worked oui the genus Perna,^ but nowhere does he mention Chemnitz's P. Spengleri. Perna isognomon, L. Oslrea isognomon, Linnk, Syst. Nat., ed. X, 1758, p. (599, No. 17G. - ed. XII, p. 1U9. Mus. Ludov. Ulr., p. 533, No. 120. Melind Isoijomint, — tÎKXziiis, Nova Tcstaccor. Gen., 1788, p. 23. Ostrea isognomon, — Gmelin, Syst. Nat., ed XIII, p 3338, No. 125. Perna {.•iognomiim, — Rkeve, Coiichol. icon., XI, Perna, Sp. 24. — isogonum, — Ci-essin in Martini u. Chemnitz, Concliyl. Cabin., VIII, 1 Abtli., ))]. 8, fig. 1. East of Koh Chuen, 9—10 fathoms, shells (2). Distribution: — Singapore, Mergui Archip., Madras, Madagascar and Mozam- bique, Mauritius. — Poulo Condor, Philippines, Amboina, Moluccas, Sorong, New Guinea, Thursday Isl. Of the two specimens brought home from the above-mentioned locality the larger (long. 59 mm., alt. 99 mm.) should be referred to the variety femoralis, Lam.,^ and the smaller (long. 34 mm., alt. 73 mm.) to the variety curvata, Ch.-' Perna rudis, Reeve. Permi rnilis, Reeve, Conchol. icon., XI, Perna, Sp. 20. — — — Mautini u. Chemnitz, Conchj'I. Cabin., VIII, 1 Abth., p. 31, pi. 9, fig. 6. North end of Koh Chang, 1 fathom, old coral blocks (1). Koh Kahdat, 1 fathom, sand (3). Alt. 14-98 mm. Distribution: — Jousseaume' records that one specimen of this species was taken at Obock (Gulf of Aden). Collected by Vokltzkow at Zanzibar. The present species is closely allied to P. isognomon L. A. H. Cooke'' thinks that P. rudis, Reeve, is synonymous with P. legunien, Gmel. (= linguaeformis, Reeve = laticostata, Reeve = caudata, Reeve). Perna Cumingi, Reeve. Perna Cumingii, Reeve, Conchol. icon., XI, Perna, Sp. 3. Cnmingi, — Martini u. Chemnitz, Conchyl. Cabin., VIII, 1 Abth., p. 40, pi. 15, iig. 1. Melina cumingii, — Edg. Smith, Zoolog. Collect, of H. M. S. "Alert," p. 113. ' The extremely unsatisfactory and unscientific way in wliich this has been done is much to be regretted. As an example of the superficiality which chai-actcrises the worli may be mentioned that one of the best-known species, P. isognomon L., is called P. isogonum L tliroughout the whole work. - Hist. nat. d. anim. s. vert., 2 éd., VII, p. 76, No. 5. » Chemnitz, Conchyl. Cabin., VII, 1784, p. 256, pi. 59, fig. 583. ■• Mém. de la Soc. zoolog, de France, 1, 1888, p. 219. ° Annals and Magaz. of Nat. Hist., 5 Ser., vol. 17, p. 138. 19" 148 52 The Gulf of Klong Salakpal (south end of Koh Chang); many specimens; occurred in large kimps, attached to each other by their byssus-threads. As the relation between the height and the breadth varies greatly in the difîerent individuals, I give here the measurements of 3 different specimens: long. 96 mm., alt. 75 mm. — long. 92 mm., alt. 105 mm. — long. 4 mm., alt. 5 mm. Distribution: — Annam (Dautzenberg), Australia (Reeve), Port Curtis ("Alert"). "P. ephippium h." has been recorded from the following localities:— Singa- pore, Mergui Archip., Nicobars, Mozambique and Madagascar, Mauritius. — Celebes, Philippines, Sorong (Tappauone Canefri), Port Curtis (East Australia), West Australia. The West-Indian species P. a/a/a, Gmel., bears much resemblance to P. Citmingi, Reeve; they may, however, be distinguished from each other by the radiating lines in the latter species, which give the growth-margins a crenulated appearance. But what is to become of P. ephippiuni L., if these two species are maintained? Perna nucleus, Lam. Pcina nucleus, Lamarck, Hist. nat. d. anim. s. vert., éd. 2, VII, 1836, p. 78, No. 10. — — — Reeve, Conchol. icon., XI, Perna, Sp. 4. — — Reeve, Martini u. Chemnitz, Conchyl. Cabin., VIII, 1 Abth., p. 36, pi. 13, fig. 1. Melina — Lamarck, Lamv, Bull. Mus. d'Hist. Nat. Paris, 1906, p. 314, No. 70. Perna pectinata, Reeve, Conchol. icon., XI, Perna, Sp. 2. — quadrangularis, Reeve, Ioc. cit., Sp. 6. Koli Lom, W. of Koh Chang (many specimens). 1) Long. 10 mm., alt. 14 mm. 2) Long, et alt. 9 mm. 3) Long. 7 mm., alt. 9 mm. Distribution:— Mergui Archip., Red Sea, Suez, (Natal and Bourbon, P.dentifera, Krauss). — Poulo Condor, Philippines, Samoa Isis., Fiji Isis., New Holland (Lamarck). This species is highly variable, as are all the forms belonging to this group. A. H. Cooke has enumerated the following species, which he believes to be identical with the present one: — P. nana, Gould, P. rostrata, Schuni., P. lobata, Reeve, P. spathulata, Reeve, P. dentifera, Krauss. Pinna inflata, Chemn. Pinna inflata, Chemnitz, Conchyl. Cabin., Vlll, 1785, p. 215, pi. 87, lig. 771. — — — Reeve, Conchol. icon., XI, Pinna, Sj). 5. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 1 Abth., p. SO, pi. ,i4, tig. 1. W. of Koh Chang, 20 fathoms, mud (1). Long. 136 mm., alt. 82 mm. Distribution:— Nicobars, Ceylon. — Philippines. Pinna hystrix, Hani. Pinna lujslrix, Hani.ey, Proc. Zool. Soc. London, XXVI, 1858, p. 226. — — — Reeve, Conchol icon., XI, Pinna, iigs. 60 — 61 (and the register). ' Annals and Magaz. of Nat. Hist, 5 Ser., vol. 17, 1886, p. 138. 53 149 Koh Chueii, 30 fathoms (3). 1) Long. 172 mm., alt. 112 mm. 2) Long. 183 mm., alt. 112 mm. Distribution: — Gulf of Suez, Red Sea. — Amboina, Australia. Pinna Strangei, Hani., is undoubtedly only a form of the present species with- out scales upon the ribs. L. Moklet ' records Pinna Cliemnitzi, Hani., from "the islands in the Gulf of Siam;" can this be due to erroneous determination? The Danish Expedition, at any rate, did not bring home any specimen of this species. Ci.ESsiN, in his Monograph of the genus Pinna, in "Martini and Chemnitz, Con- chylien Cabinet," figures and describes quite another species under the name of P. Strangei, Hani. Pagenstecher^ records P. hystrix-forxns from the Red Sea, and also forms having ribs without scales (from the same locality), which he names P. atropnrpnrea, Sow. Pinna attenuata, Reeve. Pinna atlenuata, Reeve, Conchol. icon., XI, Pinna, 1S58, Sp. 46. — — Menke, Mahtini U.Chemnitz, Conchyl. Cabin., Vlll, 1 Abtli., p. ö'J, pi. "iT, fig 1. — Stulcltluirii. Reeve, Conchol. icon., XI, Pinna, 1859, Sp. 64. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 1 Abth., p. 74, pi. 30, fig. 2. Off Tung Kaben, 6 fathoms, mud mixed with sand (1). Long. 173 mm., alt. 51 mm. Distribution: — Madras, Gulf of Manaar, Gulf of Suez, Red Sea. — Moluccas, Moreton Bay (Australia). The specimen from the Gulf of Siani bears a few scales on some of the raised, longitudinal ribs; this is also found often to be the case in specimens from the Red Sea.' I have given P. Stutchburyi, Reeve, as a synonym, as I cannot see any difference, worthy of mention, between these two forms.' Pinna mutica, Reeve. Pinna maiica, Reeve, Conchol. icon., XI, Pinna, ISöS. Sp. 33. — — — Martini u. Chemnitz, Conchyl. Cabin., Vlll, 1 Abth., p. 68, pi. 2(), lig. 2. Koh Chuen, 30 fathoms (1). Koh Kram, 30 fathoms (1 young s|)ecimen). Long. 38 — 147 mm., alt. 13-63 mm. Distribution: — Philippines. Pinna madida, Reeve, P. euglypta, Hani., and P. vespertina, Reeve, show great resemblance to the present species, and will perhaps prove to be synonyms of P. mutica, Reeve. Pinna serra, Reeve. Pinna serra. Reeve, Conchol. icon . XI, 1858, Pinna, Sj). 43. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., Vlll, 1 Abth., 1891, p. (iU, pi. 28, fig. 2. ' Journal de Conchyliologie, vol. 37, 1889, p. 161. - Ueber die von Kossraann am Rothen Meere gesamra. Mollusken. Lpzg. 1877, p. 30. ' For details concerning this and the variation, etc. of P. Stutchburyi comp. Pagenstechek, Ueber die von Kossmann am Rothen Meere gesamm. Mollusken. Leipz. 1877, pp. 30 — 31. ■* Professor Ed. v. Martens says in a letter to me, that these two forms: "sind einander sehr ähnlich und gehören vielleicht beide zu Einer Art." 150 54 East of Koh Chuen, 9—10 fathoms, shells (2). Long. 30 mm. Distribution:— Aden (Edg. Smith), Durban (Sowerby). — Moreton Bay, Queensland (Reeve). Note. In PI. II, Figs. 19 — 20, I have given figures of a young specimen oî Pinna sp. (taken between Koh Kut and Koh Kahdat, in 10 fathoms; 18 mm. long) with a very well-])reserved prodissoconch, which is distinctly separated from, and highly different from the later increment to the valve. (R.T.Jackson says in "Phylogeny of the Pelecypoda," Boston 1890, p. 332, when mentioning the group Perna, Avicula, and their near allies: "The genera Malleus and Pinna might be considered in this section, but I have not succeeded in getting very young specimens of either genus," and later on, p. 385, "I have not had opportunity to study the Pinnidce satisfactorily as attempts to obtain very young specimens have so far failed ;" in the specimen of a young Pinna sp. figured in his Fig. 53 the prodissoconch is also wanting). Pelseneer,' in his "System," places the genus Pinna under the order Eulamelli- branchia, near to Ostrea and Lima, while Avicula (Pteria) is found under the order Filibranchia. F. Bernard,- who has later examined the development of the shell of the gen. Pinna, has reached another opinion, though the material at his disposal, as he says, has been very small. The result of his researches is, that the gen. Pinna belongs to Mytilidae. The scanty material at my disposal prevents me from entering more fully into the question. Fam. Spondylidae. Spondylus Sinensis, Sow. Spondijlus Sinensis, Sowerby, Thesaurus Conchylioruin, 1. 1847, p. 427, pi. 87, figs. 32— 34. — — — Keeve, Conchol. icon., IX, 185(1, Sjiondylus, Sp. 7. S. of Koh Chuen, 30 fathoms, shells (1). West coast of Koh Chang, 10 fathoms, mud (1 4" ^/ä). Between Koh Chuen and Koh Chang, 15 fathoms, mud ('/a). E. of Koh Mak, 20 fathoms, mud (1). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (1 + V-'). S. of Koh Kahdat, 8—10 fathoms, mud (1). W. of Koh Kut, 15 fathoms, mud (2). Long. 3 mm., alt. 35 mm. — 46 mm., — 56 mm. Distribution: — Poulo Condor, Cochin China, Annam, China, Japan. The valves are quite white in one of the specimens from the Gulf of Siam.-' Spondylus coccineus, Lam. (Reeve). Spondylus coccineus, Lamabck, Hist. nat. d. anim. s. vert., VI, 1 part., 1819, p. 190, No. 11. — éd. 2, VII, 1836, p. 188, No. 11. — — — Reeve, Conchol. icon., IX, Spondylus, 185(>, Sp. 44. — ocellatus. Reeve, Conchol. icon., IX., Spondylus, Sp. 4;!. ^ A Treatise on Zoology, ed. by E. Ray Lankester, V, Mollusca by P. Pelseneer, London 1906, p. 263. - Recherches ontogén. et morphol. sur la coquille d. Lamellibranches. Annales d. se. natur. Zoologie, VIII, Paris 1898, pp. 45 et 85-86. ^ Comp. Dunker, Index moll. mar. Japon., 1882, p. 245. 55 151 Koh Chuen, 30 fathoms (on Pinna lujstrix, Hani.). Koh Mak, .sandy coast (■'/2). North end of Koh Chang, 1 fathom, old coral blocks; a very large specimen (long. 79 mm., alt. 76 mm., crass. 42 mm.). Besides agreeing well with Reeve's figure of ocellatus it closely resembles his figure and description of Sp. spectrum, Reeve. Long. 23 mm., alt. 28 mm. — 13 — — 13 mm. Distribution: — Singapore (2 — 3 fathoms, attached to coral reefs; Danish Exp. to Siam), Mauritius and Cargados (coccinens. Lam.). — Amboina and Flores (coccinens, Reeve), Philippines {ocellatus, Reeve, and coccineus, Reeve), Torres Strait (ocellatus, Reeve), Lifu (ocellatus. Reeve). The specimen taken at Singapore (long. 18 mm., alt. 23 mm.) entirely agrees with Sp. plnrispinosus. Reeve (v. Martens records this species from the Mergui Archipelago); in this specimen, and also in the young specimen from Koh Chuen, the somewhat flattened spines are furnished with a row of small teeth along each of the two sides; these teeth are visible, however, only under the lens, and is found, undoubtedly, only in quite young specimens. Spondglus maculatus, Chemn., is very closely allied to the present species (I have had Chemnitz's original specimen for examination), but as the original specimen is rather worn, no definite conclusion can be drawn at present. It is doubtful whether Reeve's coccineus is identical with Lamarck's species of the same name. v. Martens ' states that coccineus. Reeve, is identical with Spondylus zonalis, Lam. (For further details see S. spectrum, Reeve). Spondylus spectrum, Reeve. Spondylus spectrum. Reeve, Conchol. icon., IX, 1856, Spondylus, Sp. 49. — fragum, Reeve, Conchol. icon., IX, 1856, Spondylus, Sp. 61. East of Koh Chuen, 9—10 fathoms, shells ('/a). Long. 38 mm., alt. 43 mm. Distribution: — Poulo Condor, Philippines. After having examined Reeve's original specimens in the British Museum, I have put S. spectrum = S. fragum. Without doubt several others are synonymous with these species, for instance, camurus, Reeve, castas, Reeve, and others ; and per- haps it will be proved, when these highly variable forms have been more closely examined, that the numerous species from the Philippines and the surrounding waters (for instance, S. mus. Reeve, S. tenuispinosus, Sow., S. ducalis, Ch., S. zonalis, Lam., S. virgineus, Reeve, S. ocellatus, Reeve, S. coccineus, Lam., S. fragilis, Sow., S. Nicobaricns, Ch., S. auranfias. Lam., S. uariegatus, Ch., and others), in which the young valves are ornamented with dark dots and spots, but later on have a very di lièrent sculpture and colour-ornamentation, are only varieties of the same form. I have at my disposal, a very considerable quantity of material of the West Indian ' Ruinphius Gedenliboek, 1902, Die Mollusken, |). 128 (2(1). 152 56 species S. spathuliferus, Lam., which presents an almost incredible variability con- cerning the colour-ornamentation, and the occurrence and arrangement of spines, spatulate scales, etc.; but they may all be at once recognized by the characteristic colours and appearance of the young valve which is insensible to other influences. With such an example for consideration, I think it very probable that my supposi- tion concerning the relationship between some of the East Indian forms, will prove to be right. Spondylus Layardi, Reeve. Spondyliis Layardi, Reeve, Conchol. icon., IX, Spondylus, IS.'JH, Sp. Gfi. Strand of Koh Kahdat (Va). Long. 27 mm., alt. 26 mm. Distribution:— Ceylon (Cuming), Gulf of Manaar (Thurston, Standen & Leiceister). Plicatula imbricata, Menke. PUcahila imbricata, Mknke, Mollu.scor. Novae HoUandiae specini., 184,'!, p. 35, No. 196. — — — Hanley, Catalogue of recent bivalve shells, p. 288. — _ _- SowERBV, Tliesaurus Conchyl., I, p. 437, No. fi, pi. 90, fig. fi; pi. 91, figs. I,'') -18. — — — SowERBY in Reeve, Conchol. icon., XIX, 1874, Plicatida, Sp. 4. — chinensis, MoncH, Catal. conch, quæ reliq. Yoldi, II, 1853, p. 01, No. 761). Between Koh Rin and Cliff Rock, 15 fathoms (^/i). Koh Kram, 30 fathoms (1). N. of Koh Kam, 5 fathoms, gravel (Va). Off Koh Kam, 10 fathoms, gravel (1). North side of Koh Mesan, 10—15 fathoms, stones (1 -{- '^li). Between Koh Mesan and Cape Liant, 5 — 9 fathoms (^l-i). Between Koh Mesan and Koh Chuen, 25—38 fathoms, stones and shells (2). Koh Chuen, 10-30 fathoms (1 + 2/3). E. of Koh Chuen, 9—10 fathoms, shells (V2). S. of Koh Chuen, 30 fathoms, shells (1 + -Vs). Gulf of Rayong, 7 — 10 fathoms, sand, mud, shells (-/a). North end of Koh Chang, 1 fathom, old coral blocks (',2). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (2). Long. 7 mm., alt. 8 mm. — long. 28 mm., alt. 33 mm. Distribution: — Singapore (Danish Exp. to Siam, and Sv. Gad), Andamans (Melvill & Sykes), Aden (Shopland), Gulf of Tadjourah (Gravier, Anthony), He Cameran, subfossil (Jousseaume), Mascarenes (v. Martens). — China (Hanley), Philippines (Sowerby), Amboina? (Edg. Smith), Torres Strait (Melvill & Standen), West Australia (Menke, Hanley), Port Jackson and Port Stephens (Angas), I'unafuli Atoll? (Hedley). (Sowerby records it also from Honduras Bay). The species belonging to the genus Plicatula, owing to their great variability, are exceedingly difficult to define and to characterize. Hence, numerous species have been established which cannot be maintained and many erroneous determina- tions have been made, which have resulted in the records of the geographical distribution of the species frequently becoming quite misleading. Thus PI. spondy- loidea, Meuscli. (= Pl.ramosa, Lam.),' has been recorded, e. g. from: Aden (Jousseaume), ' PI. spondyloidea, Meusch. = PI. ramosa, Lam. = Barbadensis (Petiv.), d'Orb. = plicata, Chemn. = cristala, Lam. = renifonnis, Lam. := gibbosa, (Lam.) Sow. ■— marginata. Say. 57 153 the Red Sea (Sturanv, Pagenstecher, and others), Suez (Vaillant), Mauritius (v. Martens), Mozambique (Peters), Querimba Isl. (v. Martens), Pouio Condor? (RocHEBRUNE, P. reniformis, Lam.), Ciiina (Mitchell), Lord Hood's Isl. (Sowerby), and also from the east coast of North, Central, and South America, from Cape Hatteras to Patagonia (d'Orbigny, Morch, Krebs, Sowerby, Adams, Pagenstecher, Dall, Edg. Smith, Beau, and others). — It will doubtless be proved later, that several of the species closely allied to P. imbricata, Mke., are synonymous with it, e. g. P.depressa, Lam. (from Singapore and Mergui Isl., v. Martens'), P. Nouae Zelandiae, Sow. (New Zealand), P. Essinglonensis, Sow. (Port Essington), P. Philippinarum, Hani. (Philippines, Sowerby; Red Sea, Cooke; Hong-kong, Frauenfeld). P. Ceylanica, Sow. (Ceylon), P. Australis, Lam.'- (Philippines, Hanley; Australia, Lamarck, Hedley), P. horrida, Dunk. (Japan and China, Dunker), P. aculeata, Sow., and others. — Among the specimens from the Gulf of Siam several individuals occur, which agree both with the figure given by Reeve (PI. 1, Fig. 4c) and that by Sowerby (PI. 90, Fig. 6), they bear a very close resemblance to corresponding individuals of P. spondyloidea, Meuscli., from St. Thomas. Fam. Pectinidae. Pecten pyxidatus, Born. Ostrea pyxidata, Born, Testaeea Musei Cæsarei Viiulobon., 1780, p. 108, pi. 6, figs. 5 — G. Pecten pfixidatus, — Reeve, Conchol. icon., VIII, Pecten, Sp. 96. — — — Martini u. Chemnitz, Concliyl. Cabin., VII, 2 Abth., p. 57, pi. 15, figs. 5— fi; pi. 35, figs. 1-2. — — — Fischer, Catalogue d. Moll, de I'ludo-Chine, p. 209. — crehricostdltis. Philippi, Abbild, u. Beschreib, neuer od. wen. gekannt. Conchylien, I, p. 100 2), pl. 1, fig. 2. Common from Koh Lan to Koh Kut, 6 — 30 fathoms, mud and clay. Gulf of Siani, west coast of Cambodja (Crosse & Fischer). Long. 8—36 mm. Distribution: — Singapore (2 — 3 fathoms, coral reef. Dr. Mortensen), Mergui Arehip., Andamans, Tranquebar, Gulf of Manaar, Persian Gulf, Gulf of Oman. — Annam, China, Philippines. Pecten senatorius, Chemn. (Gmel.). Pallium scnutoris, Chemnitz, Conchyl. Cabin., VII, p. 320, pi. 65, fig. 617. Ostrea senatoria, Gmei.in, Syst. Nat., ed. XIII, 1700, p. 3327, No. 61. Pecten senatorius, — Reeve, Conchol, icon., VIII, Pecten, Sp. 81. ■ — — — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abth., pp. 63 and 83, pi. 16, fig. 7; pi. 21, fig. 4. — — — Edc. a. Smith, Challenger Report, Laniellibranchiata, 1885, p. 300. ' LiENARD records it from Mauritius, but v. Martens considers it (in: Mollusken d. Maskarencn u. Seychellen, p. 137) to be "wahrscheinlich amerikanisch." - non P. Anstralis, Krauss ifroin Natal) -^ muttijilicata, Desli. D.K. 1). Vidensk. Selsk. Skr, •;. K:uUki-, n;iliirvidensk.iig math AM V. 3. 20 f V 154 58 Among the Pec/e;i-species this was the one which was taken most frequently; from Koh Rin to Koh Kut in 5 — 38 fathoms, on a bottom of mud and shells. Long. 4—67 mm. Distribution: — As the question regarding the variations in form of the present species has not yet been quite settled, its distribution cannot be given with any certainty, but the following localities may doubtless be regarded as certain: — Salanga, Mergui Archip., Madras, Gulf of Manaar, Bombay, Karachi, Persian Gulf, Maldive Archip., Gulf of Aden, Red Sea, Gulf of Suez, Mauritius, Inhanibane (SE. Africa). — Philippines, China, Japan, Rlitang (post-tertiary), Moluccas, Torres Strait, Mast Head Reef (Queensland), New Caledonia. The considerable variations in form, to which the present species is subject, have caused that an enormous number of dilTerent names has been given to it. Edg. A. Smith^ has enumerated a large number of these forms, most of which can scarcely be regarded as varieties. The large quantity of material brought home from the Gulf of Siam shows plainly the variability of the species, both as regards sculpture and colour. The form porphyreus, Chemn.,^' occurs most frequently; there are developed upon it, when the individuals have reached a certain size, smaller ribs on each side of the main ribs, which thereby become tripartite; the whole surface is closely covered with scale-sculpture; this form strongly recalls P. asperrimus, Lam. [P. australis, Sow.). I have compared Chemnitz's original specimen of P. por- phyreus, which is in the Zoological Museum of the University of Copenhagen, with the specimens from the Gulf of Siam; they correspond in all respects with the latter. E. v. Martens-' distinguishes, but scarcely correctlj', between P. porphyreus, Chemn. (= P. senator his. Reeve, non Chemn.), and P. senatorius, Chemn.; these forms cannot be kept distinct from each other, as transitional forms occur. In the Gulf of Siam are found specimens, some with quite smooth ribs, and others with strong scale-sculpture on all the ribs. Bavay* thinks thai P. splendiduhis. Reeve, belongs to the variety-series of P. senatorius. Pecten rugosus, Sow. (PI. Ill, Figs. 1-2). Pecten rujjosus, Sowf.rby, Thesaurus Coiichyl., I, Pecten, p. Oö, No. 64, pi. 19, fig. 22(5. — — — Reeve, Conchol. icon., VIU, Pecten, Sp. 144. — — — Martini ii. Chemnitz, Conchyl. Cabin.. VII, 2 Abtli., p. 2,32, pi. (il, fig. 8. ' Zoology of the voyage of H. M. S. Challenger. Report on the Lamellibranchiata, p. 300. - 1 have at ray disposal several specimens from tlie Gulf of Siam which correspond exactly with the figure in Savigny, Iconographie d. Mollusques de l'Egypte, pi. 13, fig. 5, 2 of "Pecten australis, Sowerby' (IssEi., Malacol. d. Mar Rosso, p. 372). In my opinion this figure represents most closely a very well- preserved individual of P. senatorius, Ch. var. porphyreus, Ch. ' Die Mollusken d. Maskarenen u. Seychellen, 1880, p. 138. — Journ. of the Linneaii Soc, Zoology, vol.21, 1887, p. 202. — Rumphius Gedenkhoek, 1002. Mollusken, p. 12(i il8). * Bull, du Museum d'Hist. Nat. Paris, 1904, p. 306. 59 155 S. of Koh Chuen, 30 fathoms, shells ('/j). From Koh Chuen to Koh Chang, 15 fathoms, mud ('/s). S. of Koh Biciang, 9 fathoms, shells {^h). E. of Koh Mak, 20 fathoms, mud {^l-i). Between Koh Kut and Koh Kahdal, 10 fathoms, shells ('1/2). W. of Koh Kut, 15 fathoms, mud C'/s). I.ong. 7—25 mm., alt. 8—26 mm. (1 specimen long. 22 mm., alt. 25 mm.). Distribution: — Philippines. I am relying upon Ed. v. Martens's identification, in referring these forms to P. rugosus, Sow. ; as may be seen from my figures, the forms in question are very ditferent from those of Sowkkby (Ri:kve). In my specimens, the intercostal parts are not always smooth, but are often irregularly striated. Edg. Smith considers P. rugosus, Sow., to belong to a series of forms which will probably prove to be varieties of P. senntorius, Ch. Young specimens are in many cases difficult to distinguish from the young of P. senatorius, Ch. Pecten Singaporinus, Sow. Peclen Singaporinus, Sowemuy, Thesaurus Conch., I, p. 74, pi. 13, fig. 55; pi. 14, fig. 71. — — — Reeve, Conchol. icon., VIII, Pecten, Sp. 74. — - — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abth.. p. 94, pi. '25, figs. 2-4. — — — P. Fischer, Catalogue d. Mull, de I'lndo-Chine, p. 2U!). The coast of Lem Ngob (^/a). Long. 28 — 48 mm., alt. 25—51 mm. Distribution:— Singapore, Madras, Gulf of Manaar, Bombay, Gulf of Aden. — Annam, Hong-kong, Port Curtis (East Australia). Edg. A. Smith ' considers P. pica, Reeve (from New Zealand), and P. Cumingii, Reeve (from Moreton Bay), to be identical with the present species. Pilsbrv,- has described from Japan an allied form, with fewer ribs, under the name of P. Awayïensis. Pecten cretatus, Reeve. Pecten cretatus, Reeve, Conchol. icon., VIII, lS5:i, Pecten, Sp. 129. — — — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abth., p. 172, pi. 47, figs. 8— 9. North of Koh Kahdat, 4—5 fathoms, coarse sand ('/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells ('/a). Long. 5 — 7 mm. (long. 7 mm., alt. 7 mm.). Distribution unknown. Pecten nux, Reeve. Pecten nux, Reeve, Conchol. icon., VIII, 1853, Sp. 143 (see Sp. 149). N. of Koh Kahdat, 4 — 5 fathoms, coarse sand (Va). Long. 7 mm., alt. 7 mm. ' Report on the zoolog, collect, made during the voyage of H. M. S. "Alert." Loud. 1884, p. 115. - Proc. Acad. Nat. Hist. Philadelphia, 1905, p. 121. 20- 156 60 Distiilju I ion: — Maldive Archip. (Edg. Smith). — Nukahiva, Marquesas Isl. (Reeve). P. sugillatus, Reeve, is closely allied lo the present species. Note. Pecten hybridus, Gniel. {P. squamosus, Gmel.), was taken by the Danish Expedition at Singapore in 2 — 3 fathoms, on coral-reefs. Pecten (Pallium) plica L. Ostrea plica, Linné, Systema Nat., ed. X, 17,58, p. Ii97, No. 162. — ed. XII, p. lUS, No. 192. — Mus. Ludov. Ulr. Reg., p. 526, No. 10(i. Pecten — — Reevk, Conchol. icon., VIII, Pecten, Sp. 16. — — — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abtli., pp.53 and 96, pi. 14, figs. 3 — 4; pi. 26, fig. 4. — plicatiis, Chemnitz, Conchyl. Cabin., VII, p. 292, pi. 62, fig. 598. E. of Cape Liant, 9 fathoms, shells (1). S. of Koh Chuen, 30 fathoms, shells (2). Long. 41 — 42 mm., alt. 44—46 mm. Distribution:— Nicobars, Ceylon and Gulf of Manaar, Persian Gulf, Gulf of Oman, Maldive Archip., Gulf of Aden, Red Sea and Gulf of Suez. — China Sea, Japan (Nagasaki). Pecten subplicatus, Sow. Pecten siil'plicdiits, Sowuhby, Tliesaurus Conch., I, 1842, p. 64, pi. 13, fig. 37; pi. 14, ligs. 72, 73 and 81. — — — Heeve, Conchol. icon., VIII, Pecten, Sp. 17. — — — Martini u. Chemnitz, Conchyl. Cabin., p. 157, pi. 44, figs. 3 — 5. Koh Kram, 30 fathoms (1). North side of Koh Mesan, 10 — 15 fathoms, stones (1). 1 mile south of Koh Chuen, 30 fathoms, shells ('/2). Koh Kahdat, 1 fathom, sand ('/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells ('/s). N. of Koh Kut, 15 fathoms, mud ('/2). Long. 15—30 mm., all. 15—33 mm. Distribution: — Gulf of Aden. — South Japan, Philippines, Moluccas, Celebes. Pecten velutinus, Sow., in my opinion is identical with the present species. ' Pecten fulvicostatus, A. Adams & Reeve. Pecten fulvicostdlas, A. Adams & Keicve, Mollusca of the voyage of H. M. S. Samarang, 1848, p. 74, pi. 21, fig. 11. — — — Reeve, Conchol. icon., VIII, Pecten, Sp. 123. — — — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abth., p. 226, pi. 6(1, fig. 6. — Drimji, Reeve, Conchol. icon., VIII, 1853, Pecten, Sp. 152. — — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abtli., p. 207, pi. 55, figs. 7— 8. — liiculenla, Reeve, Conchol. icon., VIII, 1853, Pecten, Sp. 59. - — luculentus, — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abth., p 170, pi. 47, fig. 3. ' Küster has expressed the same opinion in his Monograph of Pecten in Martini & Chemnitz, loc. cit. p. 96. - A. H. Cooke, Ann. and Mag. Nat. Hist., Ser. 5, vol. 17, p. 134. — Bavav, Bull, du Museum d'Hist. Nat. Paris, 1904, p. 366. 61 157 Koh Kram, 20—30 fathoms (4). Between Koh Mesan and Cape Liant, 9 fathoms (1). South of Koh Chuen, 30 fathoms, shells (1). Between Koh Mesan and Koh Chuen, 25-38 fathoms (1). Long. 9—19 mm., alt. 10 — 23 mm. « Distribution:— Gulf of Aden (luculentus, Reeve var.), Red Sea. — Sulu Archip., North Australia, Bathurst Isl. (north-west coast of Australia), Port Molle (Queensland), Cape Capricorn (East Australia), Paumotu Isl. Pecten (Vola) Sannionis, Chemn. Pallium Sannionis, Chemnitz, Conchyl. Cabin,, VII, p. 313 (p. p. synonym.), pi. (i5, fig. «14. Pecten spectalnlis, Reeve, Conchol. icon., VIII, 1853, Sp. 128. — — — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abth., p. 61, pi. l(i, fig. 3. — — — Dunker, Index molluscor. mar. Japon., 188'i, p. 241, pi. XI, figs. 12 — 13. — histrionicus, Gmelin var., Petit, Journ.de Conchyl., IV, 1853, p. 150; pi. 5, fig. 2. Koh Chuen, 9—38 fathoms, shells (1 + -'2). Between Koh Kut and Koh Kahdal, 10 fathoms, shells (^/s). Long. 22—30 mm. Distribution: — Mauritius (Rohillaud). — Japan, Nagasaki (Lischke,Dunker). Chemnitz's original specimen exists in the Zoological Museum of the University of Copenhagen; on comparing it with the specimens from the Gulf of Siam, ' it will be seen that the colouring in the latter is less variegated and conspicuous, but the shape and the characteristic hollow ring-sculpture on the ribs are the same. I have re-introduced Chemnitz's name, hitherto ignored, which has the priority. The species P. histrionicus, which was afterwards established by Gmelin, and which is moreover badly characterized (Reeve's figure and description also scarcely repre- sent the species correctly), needs to be more thoroughly investigated on the basis of a greater quantity of material than has hitherto been the case. Pecten (Chlamys) madreporarum, Petit (Sow.). Perlen niadieporarnnt, Petit, Sowerby, Thesaurus Conch., I, p. 68, pi. 14, fig. 68. — — — Reeve, Conchol. icon., VIII, Pecten, Sp. 117. — — — Martini u. Chemnitz, Conchyl. Cabin., VII, 2 Abth., p. 131, pi. :i(i, fig. 6. — — — P. Fischer, Catal. d. Moll, de I'lndo-Chine, p. 209. — — Sov*'ERBV, Ch. Hedi.ev, Australian Museum, Sydney, Memoir III, 18Ü6 — l'.)U(), p. 4!)4. North end of Koh Chang, 1 fathom, old coral blocks (^/a). Long. 20 mm., alt. 24 mm. Distribution:— Singapore, Poulo Condor, Philippines, Java, New Guinea, Torres Strait, North-east Australia, Fitzroy Isl., New Caledonia, Funafuti (EUice Isl.). Amussium paucilirata, Smith. Amussinin paucilirata, Eog. Smith, The Fauna and (jeography of the Maldive and Laccadive Archipelagoes II, 1903, p. 622, No. 301, pi. 36, figs. 23— 24. ' These correspond exactly with Dunker's figures in "Index moll. mar. Japon," loc. cit. 158 62 West of Koh Kill, 30 falhonis, sand and nuid (Va). Long. 6 mm., all. 6 mm. Distribution:— S. Nilandu Atoll (Maldive Isl.). In the collections of the Danish Expedition from the Gulf of Siam only one small, transparent, white valve, the left, is found; in this the interior posterior lira is very slightly developed. Amussium pleuronectes L. Ostiea pleuronectes, Linnk, Systeina Nat., ed. X, 1758, p. 69B. — ed. Xll, p. 1140, No. 1!)0. — Mus. Ludov. Ulr. Reg. 1764, p. 524. I'ccten — — Maütini u. Chemnitz, Conehyl. Cabin, VII Bd., 2 Abth., p. 40, pi. 13, fig. 4. — — — Reeve, Conchol. icon., VIII, Pecten, Sp. 48. Commonly distributed from Koh Lan to Koh Kut, 8—30 fathoms, mud. Long. 7—87 mm. Distribution: — Andamans, Madras, Negapatam, Ceylon. — Poulo Condor, China, Formosa, Japan, Philippines, Moluccas, Java, New Guinea, Torres Strait. Flinders and Clairmont Isis. (North-east Australia). The number of the internal ribs in the valves varies greatly, therefore Amus- sium Balloti, Bernardi, ' can scarcely be maintained as a distinct species. Order Eulamellibranchiata. Fam. Limidae. Lima (Mantellum) fragilis, Chemn. Pcclen fragilis, Chemnitz, Conehyl. Cabin., VII, 1784, p. 349, pi. 68, fig. 650. Lima — — Sowehby, Thesaurus Conehyl.. I, 1847, p. 86, No. 14, pi. 22, ligs. 34— 37. — — — Reeve, Concliol. icon., vol. 18, Lima, Sp. 18. — — — P. Fischer, Catalogue d. Mollusques de I'lndo-Chine, p. 210. Koh Kram, 30 fathoms (Vs). Gulf of Rayong, 7 — 10 fathoms, sand, mud {'^h). Between Koh Chuen and Koh Mesan, 15 fathoms, mud (Va). S. of Koh Kahdat, 8-10 fathoms, mud (Va). Koh Kahdat ('/a). S. of Koh Mak, 5-6 fathoms (Va). Long. 5 — 15 mm., alt. 8—26 mm. Distribution:— Singapore, Mergui Archip., Nicobars, Persian Gulf, Lacca- dive and Maldive Archip., Suez, Mauritius, Mozambique. — Poulo Condor, Philip- pines, Amboina, New Guinea, Timor, Sorong, Torres Strait, North and East Australia, ' .lourn. de Concliyl., IX, 1861, p. 46. G3 159 New Caledonia, Sandwich Isis., Fiji Isis., Funafuti (Ellice Isl.), Gilbert Isis., Society Isis. Several authors (E. v. Martens, and others) give L. Unguatula, Lam., as a synonym of the present species. Lima (Mantellum) angulata, Sow. Lima cmgiilata, Sowerby, Tliesaurus Conchyl., 1, 1843, p. 80, No. 12, pi. 22, figs. 39 — 40 (and as L. apertii, fig. 29). — — — Reeve, Conchol. icon., vol. 18, Lima, Sp. 13. Radula {Manfellum) angulata. Sow,, Angas, Proc. Zool. Soc. London, 1865, p. (iSG. Lima angulata. Sow., Edc. Smith, Lamellibranchiata of the Challenger E.\ped., p. 280. — orientalis, Adams and Reeve, The Zoolog}- of the voyage of "Samarang." Mollusca, 1848, p. 75, pi. 21, fig. 7. Radula Mantellum) orientalis, Adams & Reeve, Anga.s, Proc. Zool. Soc. London, 1871, j)!. 101. Lima Basilanica, Adams & Reeve, op. cit., p. 75, pi. 21, fig. 6. Koh Kram, 30 fathoms (1). Koh Mesan, 15 fathoms, stones ('/a). Between Koh Mesan and Cape Liant, 5—9 fathoms, sand (^i). S. of Koh Chuen, 30 fathoms, shells (2). North of Koh Chang, 1 fathom, old coral blocks (1). N. of Koh Kahdat, 4 — 5 fathoms, coarse sand {^i-j dead). Koh Kahdat, 1 fathom, sand (^/-' dead). S. of Koh Mak, 5—6 fathoms (Va). Long. 5 — 17 mm., alt. 6'/2- 26 mm. Distribution: — Madras, Gulf of Manaar. — Philippines, North, East, and South Australia, New Caledonia, New Zealand, Funafuti (Ellice Isl.). Recorded aKso from Panama and the Bay of Carracas by Cuming and Carpenter. Lima (Mantellum) dentata. Sow. Lima dentata, Sowerby. Thesaurus conchyL, I, 1843, p. 87, No. 17, pi. 22, figs. 30^31. — — — Reeve, Conchol. icon., vol. 18, Lima, Sp. 14. — — — Hanlev, Catalogue of rec. biv. shells, p. 208. North end of Koh Chang, 1 fathom, old coral blocks (8). Koh Kahdat, 1—5 fathoms, sand, and stones (1). Long. 11 mm., alt. 20 mm. (sp. maj.). — 4 mm., — 8 mm. (sp. min.). Distribution unknown. Note. Lima squamosa, Lam., was taken by the Danish Expedition at Singapore, on coral reefs, in 2 — 3 fathoms (two specimens; long. 12 — 27 mm., alt. 16—37 mm.).' The ^'Radula squamosa, Lam., var.? interlirala" mentioned by Morch ^ is founded on an ' For further details regarding this species consult: — Lischke, Japanische Meeres-Conchylien, I, pp. 102-64; 11, pp. 155—56. — E. v. Marten.s, Rumphius Gedenkboek. Mollusken, 1902, p. 18. (Li'mn Sotverbgi. Dsh.). — Rl'cql'OY, Daitzenberg et Doli.fis, Les Mollusques marins du Roussillon, II, p. 51. {Radula lima L.) — Edg. Smith, Lamellibranchiata of tlie Challenger Expedition, p. 287. — Melvili,& Standen, Journ. of the Linn. Soc. Zoology, vol. 27, p. 182. — Tappabone Canei-ri. Annali d. Mus. Civ. di St. Nat. di Genova, IX, 1876—77, p. 300. - Catalogus concliyl. quæ reliq. com. dc Voldi, II, 1S53, p. 57. The original s|)ecinien is in my collection. 160 64 older individual of L. squamosa, Lam., in which have developed, between some of the central ribs towards the ventral margin, very slight indications of a rib; the lines of growth also are somewhat prominent; these being individual characters, the form can by no means be maintained as a variety. Fam. Ostreidae. Ostrea cucuUata, Born. Ostrea cuciilhild, Born, Testacea Musei Cæsarei Vindobon., 17H(), p. 114, pi. VI, figs. 11 — 12. var. Barclaijana, Sowerby. Reeve, Conchol. icon., XVIII, 1871, Ostrœa, Sp. 77. Koh Chang, on stones at the strand (many specimens). Coast of Lem Ngob (2). Coast of Koh Kahdat (1). Long. 35 mm., alt. 42 mm. var. Forskâli, Chemnitz. Concliyl. Cabin., VIII, 1785. p. 150, pi. 72, fig. ()71. South of Koh Chuen, 30 fathoms, shells ('/a). Coast of Koh Chang (2). Long. 37 mm., alt. 55 mm. "Bangkok" (Coll. Dautzenberg). Young individuals of both forms were found in several places in the Gulf of Siani. Ed. v. Martens records' that he has taken numerous specimens of 0. cuciillata, Born, at Bangpra in the Gulf of Siam. Distribution: — Salanga, Mergui Archip., Nicobars, Ceylon, Bombay, Persian Gulf, Gulf of Aden, Red Sea, Suez, Mozambique, Queriinba Isis., Mascarenes, coast of Natal, Ascension Isl. — Poulo Condor, Cochin China, China, Formosa, Loo-Choo Isis., Japan, Philippines, Sumatra, Moluccas, Timor, Thursday Isl., Mast Head Reef (Queensland), South Australia (?Angas), Viti Isis., New Zealand. Deshayes,^ characterizes this oyster very correctly when he says that it "aurait mérité le nom de multiformis" because its variability is exceedingly great, and consequently, as maj' be expected, it has an endless number of synonyms;'^ to these the following, besides many others, may doubtless be added: — 0. circiimsuta, Gould, ^ 0. attenuata, Sow.,' and perhaps 0. vitre facta. Sow." Specimens of O. t«CJ/Z- ' Zoolog. Ergebnisse ein. Reise in Niederl. Ost-Indien brsg. v. M. Webeh, IV, 1897, p. 223. ^ Catal. d. Mollusques de l'ile de la Réunion, 18()3, p. ;i(). " For further details cf. Pagenstecheh, Ucber d. v. R. Kossmann am Rothcn Meere gesamni. Mol- lusken, 1877, pp. 1(1 — 24. — Sturany, Lamellibrancbiaten d. Rothen Meeres, 1899, p. 37. — Lischke, Japani.sche Meeres Concliyl., 11, p. ICI. — Cooke, Ann. and Magaz. Nat. Hist., Ser. ö, vol.17, p. 134. * Gould, Unit. States Kxplor. E.xpedit., pi. 43, fig. 576. ~ Reeve, Concliyl. Cabin., XVIII, (hliea, Sp. Ü4. Why Reeve records "Massachusetts?" as its habitat is difficult to understand, as Gould (Proc. Boston See. of Nat. Hist., 1850, p. 346) says that his species was found in the "Feejee and Samoa Is- lands." Angas (Proc. ZooI. Soc. London, 1867, p. 934) records it from Botany Bay. ■' Reeve, loc. cit. Sp. 49. '^ Reeve, Ioc. cit. Sp. 8U. 65 IBl lata, Horn (and var. Forskåli, Chemn.), were taken in Pliocene Deposits in Egypt "in the Lake Deposits of Wadi Nalrun at tlie hill known as Moluk." ' Ostrea hyotis L. Mtjlilus Ilijotis, I.INNK, Syst. Nat., ed. 10, 1758, p. 7(14, No. 207. — ed. 12, p. 1155, No. 244. — Mus. Ludov. Ulr., p. 538, No. 129. Ostriva bi/otis, — Reeve, Conchol. icon., XVIII, 1870, Ostrœa, Sp. 7. Var. imbricata, Lamarck. Ostrea imbricata, Lamarck, Hist. nat. d. anim. s. vert., VI, 1 part. 1819, p. 215, No. 4fi. — éd. 2, VII, 1836, p. 235, No. 46. Ostrœa — — Reeve, Conchol. icon., XVIII, Ostra-a, Sp. 36. Koh Kram, 30 fathoms ('/a). S. of Koh Chuen, 30 fathoms, shells (''/j). Coast of Lem Ngob (1). S. of Koh Kahdat, 8 — 10 fathoms, mud (1). E. of Koh Mak, 20 fathoms, mud (1) (Singapore; Sv. Gad. '/a). Specimen from Koh Kram: long. 74 mm., alt. 46 mm. — — Koh Kahdat: long. 33 mm., alt. 49 mm. — — Koh Chuen: long. 21 mm., alt. 24 mm. — — Koh Mak: long. 57 mm., alt. 49 mm. Distribution: — 0. hyotis has been recorded from : — Ceylon, Gulf of Manaar, Gulf of Aden, Seychelles, Amirautés, Mauritius, Zanzibar. — Poulo Condor, China, Loo Choo Isis., Japan, Philippines, Moluccas, Viti Isis. 0. imbricata has been recorded from : — China, Japan, Java, New Guinea, and by Melvill & Standen from the Persian Gulf and the Mekran coast. Since Deshayes (in the second ed. of Lamarck, Anim. s. vert.) wrote regarding 0. imbricata that "Cette espèce est inutile, elle a été faite avec une variété jaune de la suivante (0. hyotis, Ch.); il faudra donc les réunir sous la dénomination d'Ostrea hyotis," some later authors have upheld the specific distinctness of both the species (Dunkek, Reeve, Pilsbry), some regard them either as varieties or as the same species (Küster, Hanley, Mørch). 0. inermis, Sow., is no doubt synonymous with 0. imbricata, Lam. Ostrea rivularis, Gould (Lischke). Ostrea riuularis, Gould, Proceed. Boston Soc. Nat. Hist., vol. VlII, 1861, p. 39. — — — Lischke, Japanische Meeres Conchyl., I, 1869, p. 176, pi. 14, figs. 2—3. Gulf of Rayong, 7 — 10 fathoms, sand and mud (i/a). S. of Koh Samit, 20 fathoms, mud ('/a). Coast of Lem Ngob (1). Sound of Koh Chang, 5 fathoms, soft clay (4). E. of Koh Mak, 20 fathoms, mud ('/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (one specimen, and some young odd valves). Strand of Koh Kahdat (-/a) (Singapore, shallow water, one specimen; Sv. Gad). ' R. Bullen Newton, On some Pliocene and Post-Pliocene Shells from Egypt (The Geological Magazine. New Ser., dec. IV, vol.6, 1899, p. 402, pi. 19, figs. 1—5). U. K U. ViilensU SeUk. Skr., 7. RiuUke, naturvideiisk. og niiitliem. Afd. V. 3. 21 162 ß(i Long. 74 nun., alt. 54 mm. — 59 mm., — 64 mm. Distribution:— China Sea, Nagasalu, Yaeyania {'?). A few of the specimens collected were attached to Mangrove-roots. Futnre comparative investigations will doubtless prove that 0. riviilnris, Gould (Lischke), is only a form of a previously known species,' but I have thought it right to stop my researches at riimlaris (with which the specimens from Siam entirely correspond), as a large quantity of material is required to arrive at a reliable con- clusion. The whole group (with thin, not folded shell-margin), which includes 0. mijfiloides, Lam., nigromarginata, Sow., tiiberciilata, Lam. (= tiibercularis, Reeve), Panhicciae, Crosse (= palmipes, Sow.), the collective species arborea, Ch. and para- sitica, Gm. (which constantly reappear), and many more, must, on account of their great variability, and the hitherto very uncritical and superficial treatment to which they have been subjected, be carefully investigated and may, no doubt, be con- siderably reduced. Ostrea Paulucciae, Crosse. Ostiea Paiilncciæ, Cisosse, Journ.de Conchyl., vol.17, 1869, p. 188; vol.18, 1870, p. 108, pi. 2, fig. 5. Ostrœa palmipes, Sowerbv, Rekve, Conchol. icon., vol. 18, 1871, Ustriea, Sp. 56. S. of Koh Tulu, 10 fathoms, sand mixed with mud (-/s). Sound of Koh Chang, 5 fathoms, soft clay (1). S. of Koh Kahdat, 8—10 fathoms, mud (many young odd valves). Between Koh Kahdat and Koh Kut, 6 fathoms, sand mixed with mud (^h). W. of Koh Kut, 15 fathoms, mud (^/a). Long. 28 mm., alt. 20 mm. Distribution: — Annam, China, Philippines. At Koh Chang (in 5 fathoms, on a soft muddy bottom) a smaller specimen was obtained (long. 15 mm., alt. 18 mm.) which seems to me to agree in all points with 0. pes-tigris, Hanl.;^ it is doubtful whether this form also is entitled to rank as a species. The specimens from the Gulf of Siam do not correspond exactly with Crosse's description as regards colour, as in almost all cases they are white with a few lilac rays or shades. Note. In Morch's Catalogus conchyl. quæ rcliq. comes de Yoldi, II, p. 62, No. 783, there is recorded an Ostrea siamensis, Yoldi, from "Singapuhra," as it is, however, not described, either there or anywhere else, I cannot state anything regarding that form. ' Dunker (Index moll. mar. Japon., p. 250) refers it to 0. arboiea, Ch. - Proc. Zool. Soc. London, Xlll, 1845, p. 107. Taken bj' Cuming at Luzon, Philippines. Reeve, Conchol. icon., XVllI, Sp. 78. Sowkhby (Append, to marine shells of South Africa, 1897, p. 28) is of opinion that 0. pes-ligris (Heeve, fig. 78) is synonymous willi O htcciala, Hani. (= O.laccrans, Ueeve). 67 163 Farn. Carditidae. Cardita variegata, Brug. CiirtUlit inirieijala, HiiuGUiÈUE, Encyclopédie nictliodiciuc. Hist. nat. d. vers, I, 17'.)2, p. 407, No. (i, pi. 233, fig. G [C. cahjculata, Lain.). — — — Reeve, Concliol. icon., I, 1843, Cardila, Sp. 3. — — — Krauss, Siidafrilian. Mollusken, 1848, p. 13. Mijlilicardia — — i)i-; Rochebbune, Faune malacol. de la Cochincliinc ct du Cambodge (Bull. Soc. Philomatliique de Paris 1881, p. 12, No. 32. Cardita — — Cliîssin in Mabtini u. Cukmnitz, Conchyl. Cabin., X Bd., 1 Abtli., 1888, p. 23, No. 43, pi. 3, figs. 8-9, and pi. 11, figs. 5— 6. — — — P. Fischer, Catalogue d. Moll, de I'lndo Chine, p. 228. — cahjculata, Lamarck i non Linné), Hist. nat. d. anim. s. vert., 2 éd., VI, 1835, p. 431, No. 15. — — — SowERBY, Genera of reo. and fossil shells. Cardita, figs. 1 — 2. — snbaspera, — Hist. nat. d. anim. s. vert., VI, 1819, p. 25, No. 16. — éd. 2, VI, p. 432, No. 16. — — — Delessebt, Recueil de coquilles deer. p. Lamarck, 1841, pi. 11, fig. 9. "Siam" (P. Fischer, loc. cit.). Distribution: — Singapore, Mergui Isis., Nicobars, Ceylon, Gulf of Manaar, Maldive Isis., Ratnagiri, Persian Gulf, Gulf of Aden, Red Sea, Suez, Sej'chellcs, Amirantes, Zanzil)ar, Natal, Querimba Isis., Mascarenes. — Poulo Condor, China, Yokohama, Philippines, Sulu Isis., Java, Moluccas, Mast Head Reef (Queensland), Port Essington, Samoa Isls., Viti Isis., Lifu. The Danish Expedition collected no specimens of this species from the Gulf of Siam, but it has been taken at Singapore in shallow water (by Sv. Gad). A. H. Cooke' writes: "I cannot separate radiila, Reeve, from this species." Fam. Crassatellidae. Crassatella radiata, Sow. Crasstdella radiata, (1. B. Sowerby, Catalogue of the shells in the collect, of the Earl of Tankerville, 1825, Appendix, p. II, pi. 1, fig 2. — — — Reeve, Conchol. icon., I, Crassatella, Sp. 12. — — — Martini u. Chemnitz, Conchyl. Cabin., X Bd., 1 Abth., p. 14, pi. 6, fig. 2. — — — Crosse & Fischer, Journ. de Conchyl., vol. 40. 1892, p. 76. Many specimens taken from Koh Lan to Koh Kut, 2—30 fathoms, clay, nuid, shells, sand. Very common. Long. 2—27 mm. (sp. maj. long. 27 mm., alt. 20 mm., crass. 10 mm.). Gulf of Siam, west coast of Cambodge (Pavie). Distribution: — Singapore (Danish Exp. to Siam, 2 — 3 fathoms), Mergui Archip., Nicobars, Andamans, Gulf of Manaar, otT Mangalore (Malabar-Coast), Gulf of Aden, Red Sea. ' Annals and Magaz. of Nat. Hist., 1886, p. 101. 21* 164 68 Several specimens of a shorter, and venlricose form (long. 18 mm., alt. 13 mm., crass. 9 mm.) were taken at Koh Kahdal (in 1 — 5 fathoms, on a sandy and stony bottom); a similar form was taken at Koh Mak (in 5—6 fathoms). Fam. Astartidae. Carditella pusilla, n. sp. (PI. Ill, Figs. 3-5). This species is rounded (with the exception of the somewhat prominent beaks), a little inequilateral, dully pellucid, and whitish, (some specimens have brownish-red spots and tints); fairly thick and convex valves, provided with a broad, smooth, heart-shaped lunule, which is distinctly prominent along the middle. The sculpture consists of 12 — 13 broad, rounded, radiating ribs, which are at least 3 times as broad as the interstices between them, and are covered with close-set, fine, transverse tubercles. The umbones are acute, median in position, well in- curved, and inclined over towards the front. There is a single central, strong, acute triangular cardinal tooth in the right valve which fits in between two divergent but smaller teeth in the left. The lateral teeth are distinct on both sides, the anterior in the right valve and the posterior in the left being separated from the outer margin by a deepish groove, the posterior in the former and the front one in the latter being, on the contrary, on the margin. The hinge-plate between the cardinal and the lateral teeth is seen under magnification to be finely transversely striated. The interstices between the ribs, wherever they appear at the margin, make the latter dentate, and these teeth are each provided on the inner side with a small nodule. Long 25 mm., alt. 25 mm., crass. 2 mm. Between Koh Rin and Cliff Rock, 15 fathoms (Vs). Koh Kram, 30 fathoms (2 + '"'s)- Koh Mesan, 15 fathoms, stones (2). Between Koh Mesan and Cape Liant, 5—9 fathoms, sand {■^l■^). Between Koh Mesan and Koh Chuen, 25-38 fathoms, stones (1 + ^/s). Koh Chuen, 10—30 føthoms (''la). South of Koh Chuen, 30 fathoms, shells ('/a). Koh Kahdat, 1 — 5 fathoms, sand and stones ('/s). This species is most nearly related to Carditella infans, Edg. Smith, and in my diagnosis I have kept closely to Edg. Smith's description of that species, so that by comparing the diagnoses it may be easier to form an idea of the differences between the two species. In the British Museum there is a CarditeUa-îorm labelled "Psepbis delecta, A. Ad. (Goiildia delecta)" which is closely related to my species, but diflers from it specifically. Carditella pulchella, n. sp. (PI. Ill, Figs. «-8). This little species is oval in form, whitish, often ornamented with brownish- red spots which appear most distinctly on the interior of the valves; the shell is 69 165 thick and convex. The suiTace-sculpture consists of 13 — 14 strong, distinctly pro- minent, rounded radiating ribs wliich bear numerous rather close-set, arched scales, and transverse tubercles. The interstices between the ribs are about as broad as the ribs and have close-set, rough folds and lines of growth. The beaks are situated to- wards the anterior end, they are acute and slope rather suddenly down towards that end, which is rather pointed as compared with the truncated posterior end, towards which the dorsal side descends gradually from the beaks in a straight line. The lunule, which is smooth and oblong, projects a little along the central line. The hinge consists of a single, central, conical, triangular tooth in the right valve, which fits in between two more slender, divergent teeth in the left; the lateral teeth are well developed and equidistant. The hinge-plate between the cardinal and lateral teeth is seen under magnification to be provided with close-set, fine folds and striæ. In the interior the margin is dentate owing to the external ribs projecting there. Long. 3 mm., alt. 25 mm., crass. 2 mm. Koh Kram, 30 fathoms (3 + ^/s). Between Koh Mesan and Cape Liant, 5—9 fathoms, sand (-/s). Between Koh Rin and ClitT Rock, 15 fathoms (-/ä). E. of Koh Chuen, 9—10 fathoms, shells (1). Koh Chuen, 10—15 fathoms (^/a). Koh Chuen, 30 fathoms (1 + i/s). S. of Koh Chuen, 30 fathoms, shells (1 + '-'li). Koh Kahdat, 1—5 fathoms, sand (1 + ''/a). N. of Koh Kahdat, 4—5 fathoms, coarse sand {'/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (1). S. of Koh Kut, 17—20 fathoms, mud ('/a). Singapore, shallow water ("/a). The individuals vary greatly in regard to outline, the position of the unibones, and the sculpture. I am convinced that Card, pidchella does not become much larger than the individuals I have before me, because several of the largest specimens are greatly thickened and solid, i. e. increase in size has ceased, and growth is continued only as regards the thickening of the valves. — Card, pulcbella is most nearly related to Carditella Torresi, Edg. Smith, which is, however, larger, and differs in several essential points from my species. Fam. Cyprinidae. Trapezium angulatum, Lam. CgpHcanUa amjulata, L.^marck, Hist. nat. d. aiiim. s. vert., VI, 1819, p. 28, No. 2. — éd. 2, VI, 1835, p. 438, No. 2. — — - Deshayes, Traité élém. de Conchyliologie, II, p. 18, pi. 24, figs. 10—11 (C. angiilosa, Lam.). — — — Reeve, Concho). Icon.. I, 1843, Cypricardia, Sp. 2. Trapezium anijnhitnin, — H. &A. Adams, Genera of ree. Mollusca, II, 1858, p. 439, pi. 109, fig. 5a, b. Cypricardia (inyulata, — Hidalgo, Fauna malacol. de I. isl. Filipinas, II, 1003, p. 305, No. 462. Cluima oblonga, Linné var., Chemnitz, Conchyl. Cabin., XI, 1795, p. 238, pl. 203, figs. 1993-94. Libitina bicarinala. Schumacher, Essai d'un nouv. système d. habitations d. vers testacés. 1817, p. 1R9. pi. 17, fig. 2. 166 70 Ojpiicanlia roslrala, Lamauck, Mist. nat. d. aiiim. s. verl., VI, Itili), p. 2«, Nu. li. éd. 2, VI, ISSö, i>.4'A'.). No, 3. — — Heeve, Conchol. icon., I, 1843, Cjipricartlia, Sp. 3. Trapezium roslralnm, — Ddnkeh, Index moHuscor. mar. .lapon., 1882, p. 210. Koh Kahdal, 1 fathom, sand (2). Koh Mak, sandy coast ('/a). Long. 11 — 26 mm. D ist r ihn ti on: — Andamans, Madagascar, Manritius, He S' Marie, Natal, Durban. — Pliilippines, Japan, Aru Isl., Torres Str., Port Denison, Kangaroo Isl. (New Hoi- land), New Caledonia, Boston Isl., Viti Isl. All the specimens from the Gulf of Siam belong to the form rostrata, Lam. Trapezium vellicatum, Reeve. Cupricaidia vcllicata, Heeve, Proc. Zool. Soc. London, 184.'i, p. 195. — — — Concliol. icon., I, 1843, Cypricanlia, Sp. 7. Trapezium vellicatum, — Dunkeh, Inde.x moll. mar. Japon., 1882, p. 210. — — — var., Edg. Smith in Zoolog. Collect, of H. M. S. "Alert," Lond. 1884, p. 'J7, No. 21. Libitina vellicata, — Melvill & Syke.s, Proc. Malacol. Soc. London, 111, 1898, p. 48. Cijpricardia vellicata, — Hidalgo, Fauna malacol. de 1. Isl. Filipin., 11, 1903, p. 367, No. 463. Libilimi — — Dautzenberg & Fischer, Journ. de Concliyl., vol. SS, igo.'i, p. 213. Coast of Lem Ngob, shallow water, stones (29). Gnlf of Klong Salakpat (4). Koh Chang, shallow water, stones (5). Long. 7 — 30 mm. Distribution: — Mergui Archip., Andamans, Bombay, Karachi, Persian Gulf. — Philippines, Tonkin, China, Japan, North Australia (Port Darwin), East Australia (Port Curtis). In all the specimens from the Gulf of Siam the valves, upon their exterior and interior, are quite white without raj's or coloration at the posterior end (in some of the specimens the umbones are j)urplish-brown). Similar forms have been recorded from the Philippines (Cuming), Japan (Dunker), and North Australia (Coppinger). Coralliophaga coralliophaga, Chemn. Chama coralliophaga, Chemnitz, Conchyl. Cabin., X, 1788, p. 359, pi. 172, figs. 1673 — 74. — - — Gmelin, Syst. Nat., ed. XIII, 1790, p. 3305, Nr. 25. Cypricardia — Gmelin, Lamarck, Hist. nat. d. anim. s. vert., VI, I, 1819, p. 28, No. 4. — éd. 2, VI, p. 439, No. 4. — — Lamarck, Reeve, Conchol. icon.. I, 1843, Cypricardia, Sp. 12. Coralliophaga coralliophaga, Gmelin, H. &A. Adam.s, Genera of recent Mollusca, pi. 109, fig. 6. Cypricardia — Chemnitz, Lischke, Japan. Meeres-Conchyl., 11, p. 140. Lilhophagilla, — — v. Martens, Journ Linn. Soc; Zool., vol. 21, 1887, p. 214, No. 372. Coralliophaga — Gmelin, Verrill and Bush, Trans. Connecticut Acad., X, 1900, p. 520, pi. 63, figs. 9-10. — — Chemnitz, Hidalgo, Fauna malacol. d. las isl. Filipinas, II, 1903, p. 369, No. 467. Cardila daclylns, Hrugiiière, Encyclop. method. Vers., I, 1792, p. 412, No. 13. Coralliophaya ductyliis, Bruguière, Mørch, Catal. conchyl. quæ reliq. Yoldi, 11, p. 19, No. 199. 71 167 Trapezium daclijlus, Iîrigi'ière, H. Krebs, West-Indian mar. shells. 1864. p. IS.'i. Cutalliophaija dactylus, Bruguière, P. Fischer, Moll, de I'lndo-Chiue, p. 2;iO. — cardiloidea, Blainvili.e, Manuel de Malacol. et de Conchyl., 1825, p. 560, pi. 76, fig. .S. Ctjpricardia Hornheckiana, d'Orbigny, Moll, de I'ile dc Cuba, II, 1853, pi. 266, No. 464, pi. 26, figs. 33 — 34. — gracilis, Shutti.eworth. Trapezium — — H. Krebs, West-Indian mar. shells, 1864, p. 123. Coralliophaga striolata, H.Adams, Proc. Zool. Soc. London, 1870, p. 791, pi. 48, tig. 12. — lithophayella, Dunker (non Lamarck), Index moll. mar. Japon., 1882, p. 209. Koh si Chang (-'a). Klong Salakpat (1). Koh Chang, 1 fathom, old coral blocks (taken in great numbers). North end of Koh Chang, 1 fathom, old coral blocks (-/s). Koh Kahdat, 1 fathom, sand (1). Long. 2^32 mm. Distribution: — Mergui Isl., Aden, Red Sea, Mauritius. — Poulo Condor, Philippines, Japan, Yap Isl., Uvea (Wallis Isl.), Lord Howe's Isl. — East coast of America : Florida (Cedar Keys), Greater and Lesser Antilles. A. H. Cooke is of opinion that Reevk's C. laminata is probably synonymous with C. coralliophaga, Chemn. — Several of the specimens from the Gulf of Siam (at any rate the individual which was taken alive at Koh Kahdat, on a sandy bottom) convey the impression of not always boring in corals. It is a characteristic mark of distinction in this species that it has, on both apices, a small, dark stripe, which occurs in tlie specimens from both American and Asiatic waters. Fam. Lucinidae. Lucina (Thyasira) edentula L. r. Vi.U-iisk. Selsk. Skr.. 7. R;i-kke. naturviilcnsk. uti m.illi Alil V. 3. 24 186 90 Scintilla Candida, Desh. Scintilla Candida, Dkshayes, Proc. Zool. Soc. London, 1855, p. 177, No. 17. — — — SowEHBY, Thesaur. Conchyl., Ill, p. 177, No. 17, pi. 235, fig. 33. — — — SowKHBY in Reeve, Conchol. icon., XIX, Scintilla, Sp. 6. Koh Kahdat, 1 fathom, sand (3). Koh Kahdat, 1—2 fathoms, corals (2). North end of Koh Chang, 12 fathoms, old coral blocks (3). Long. 25 — 11-5 mm. Distribution: — Gulf of Manaar. — Philippines. Scintilla Philippinensis, Desh. Scintilla Philippinensis, Deshayes, Proc. Zool. Soc. London, 1855, p. 176, No. 14. — — - H. &A. Adams, Genera of rec. MolL, 1858, II, p. 480, pi. 115, fig. 4. — — — SowERBY, Thesaur. Conchyl, III, p. 179, No. 3(), pi. 235, figs. 31-32. — — — SowERBY in Reeve, Concliol. icon., XIX, Scintilla, Sp. 5. Koh Kahdat, 1 fathom, sand (1). Long. 9"5 mm., alt. 6 mm. Distribution: — Philippines, Sorong (Tapparone Canefri). Scintilla hydatina, Desh. Scintilla hydalina, Deshayes, Proc. Zool. Soc. London, 1855, p. 177, No. 19. — — SowERBY, Tliesaur. Conchyl., Ill, p. 180, No. 39, pi. 235, figs. 5G— 57. — — SowEKBY in Reeve, Concliol. icon., XIX, Scintilla, Sp. 38. Coast of Lem Ngob, low tide, stones (many specimens). Long, up to 6 mm. Distribution: — Philippines. S. Alberti, Smith, * from Torres Strait is very closely related to the present species. The accompanying figure drawn from a sketch of Scintilla hydatina, Desh., made by Dr. Th. Mortensen from living specimens collected at Lein Ngob, shows that the animal agrees in many points with Mobius's figure (v. Martens, Die Mol- lusken d. Maskarenen u. Seychellen, Berl. 1880, pi. 21, fig. 10) of Scintilla aurantia, Lam. The mantle, which covers both the valves, is pale yellow (the colour being due to numerous Scintilla hydatina, Desh. small, pale yellow drops which are present in the mantle), and bears many, comparatively long papillæ, which are contractile; they are smallest in the middle of the valves and become larger towards the margins, where they reach a length of about 2 mm. They do not agree in form with those figured by Möbius ' Report on tlie zoolog, collections made in the Indo-Pacific Ocean during the voyage of H. M. S. "Alert," 1881—82, Lend. 1884, p. 107, pi. 7, fig. G. 91 187 in S. aiirantia, but are apparenlly cylindrical; each is deep red ai the tip, the small papillæ in the middle of the valves being the palest in colour. There is also a red spot upon the foot, about lö mm. from its end. Fam. Tellinidae. Tellina (Tellinella) Deshayesi, Hani. Tellina Deshayesii, Hanlky, Proc. Zool. Soc. London, XII, 1844, p. 148. — — - SowEHBY, Thesaur. Conchyl., I, p. 223, No. 2, pi. 57, fig. 66. — — — Reeve, Conchol. icon., XVIl, Tellina, Sp. 200. — — — V. Bertin, Revision d. Tellinides, p. 251, No. 52. — Deshayesi, — Cho.sse et Fischer, Journ. de Conchyl., vol. 40, 1892, p. 76. (Non Tellina Deshayesii, V. Carpenter, Proc. Zool. Soc. London, 1856, p. 160, Hab. in Sinu Panamensi). Gulf of Siam, west coast of Cambodge (Pavie). Distribution: — Aden (Shopland), Red Sea (Hanley(?), V. Bertin). The Danish Expedition to Siam collected no specimens of this species. Tellina (Tellinella) Spengleri, Martini (Chemn.). Das Elfenbeinerne Schifflein oder Navet, L. Spenoler, Bescliäftig. d. Berlin. Gesellsch. Naturf. Freunde, I, 1775, pp. H87-94, pi. 9, figs. 1—3. Die Spenglerischen Dïmnmiischel, Martini, Beschäftig, d. Berlin. Gesellsch. Naturf. Freunde, 1, 1775, p. 394. Tellina Spengleri, Martini in Chemnitz, Conchyl. Cabin., VI, 1782, p. 98, pi. 10, figs. 88-90. — — — Spengler, Skrivter af Naturhistorie-Selskabet, IV, 2 H., 1798, p. 77, No. 6. — — Chemnitz, Linné, Systema Naturae, ed. XIII cur. Gmelin, p. 3234, No. 30. — — — ScHUMACHKK, Essai d'un nouv. système d. habitations d. vers test. 1817, p. 162. — — — Hidalgo, Fauna malacol. de las isl. Filipinas, 1903, p. 118. — rostrata, (Linné), Hanlev in Sowerby, Thesaurus Conchyliorum, I, 1846, p. 222, No. 1, pi. 61, fig. 157. — — — Reeve, Conchol. icon., vol. XVIl, Tellina, Sp. 83. — (Tellinella) rostrata, (Linné), RÖiMer, Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., 1871, p. 33, No. 19, pi. 3, figs. 5—7; pi. 11, figs. 4—5. — — — — V. Bertin, Revision d. Tellinidés, p. 251, No. 51. — rostrata, (Linné), Morlet, Journ. de Conchyl., vol. 37, 1889, p. 174. — — — P. Fischer, Catal. d. Moll, de I'Indo-Chine, p. 245. Hatien (Gulf of Siam) L. Morlet. The Danish Expedition to Siam collected no specimens of this species. Distri bulion:— Malacca, Nicobars, Bay of Bengal, Ceylon, Madras, Mauritius(?). — Cochin China, Philippines, Moluccas, Banka, Java. Linné, in spite of Hanley's assertion in "Ipsa Linnæi Conchylia," has certainly not been clear in his judgment of his species T. rostrata; he has evidently confused T. vulsella, T. Spengleri and T. perna under this name; therefore, I have had no hesitation in following Hidalgo's example and employing Martini's (Chemnitz's) name T. Spengleri for the present species, T. Spengleri being both described and figured very clearly. Spengler already, both in his original collection (which is preserved in the Zoological Museum of the University of Copenhagen) and in his 24* 188 92 descripliüii ol' Ihe genus Tellina, dislinclly dilTerentiates between T. rostrata L. (= vulsella, eil.) and T. Spengleri. Teilina (Tellinella) pulcherrima, Sow. Teilina pulcherrima, Sowerbv, Catal. of shells in the collect, of the Earl of Tankerville, 1825, Appendix, p. Ill, No. 184, pi. 1, tig. 1. — — — Hanley, Monogr. gen. Tellina (Sowerby, Thesaur. Conchyl., I), p. 22Ü, No. 8, pi. 61, fig. 165. — — — Reeve, Conchol. icon., XIV, Tellina, Sp. 108. — — — Bertin, Revision d. Tellinides, p. 240, No. 22. — — — Dunker, Inde.\ moll. mar. Japon., p. 189. North of Koh Kahdat, 4 — 5 fathoms, coarse sand (1). Between Koh Kahdat and Koh Kut, (5 fathoms, sand mixed with mud (Va). W. of Koh Kut, 15 fathoms, mud (^/a). Long. 29—39 mm. Distribution: — Singapore, Banca Strait, Philippines, Japan, Mast Head Reef (Queensland). Tellina (Tellinella) rugosa, Born. Tellina rugosa, Roun, Index rer. natur. Mus. Cæsar. Vindohon., 1, 1778, p. 18. — ïestacea Mus. Cæsar. Vindobon., 1780, p. 29, pi. 2, figs. 3-4. _ _ _ Chemnitz, Conchyl. Cabin., VI, 1782, p. 81, pi. 8, fig. 62. — — — Hanley, Monogr. of the gen. Tellina (Sowerbv, Thesaur. Conchy!., I), p. 267, No. 82, pi. 64, fig. 238. ' — (Tellinella) rugosa. Born, Römer in Martini u. Chemnitz, Conchj'l. Cabin., X, 4 Abth., p. 36, pi. 2, fig. 1; pi. 11, figs. 6-7. — rugosa, Born, Reeve, Conchol. icon., XVU, Tellina, Sp. 36. — (Tellinella) rugosa, Born, Bertin, Revision d. Tellinides, p. 242, No. 29. Koh Mak, sandy coast (^/a). Long. 29—37 mm. Distribution: — Ceylon, Karachi, Hulule Isl., Gulf of Aden, Red Sea, Suez, Seychelles, Mauritius, Zanzibar, Querimba Isis. — Philippines, Yaeyama (Loo Choo Isls.), Sulu Isls., Java, Ceram, Banda Isis., New Guinea, Moreton Bay (Queensland), New Caledonia, Mariannes, Lifu, Viti Isls., Funafuti (Ellice Isls.), Samoa Isls., Sand- wich Isls., Raratonga, Opara, Tahiti, Mangareva and Akamaru. Tellina (Tellinella) Hungerfordi, Sow. Tellina Hungerfordi, Sowerby, Proc. Malacolog. Soc. London, I, 1894, p. 159, No. 23, pi. 12, fig. 22. Off Koh Kam, 10 fathoms, gravel ('/ü). Koh Chuen, 30 fathoms (Vs). S. of Koh Kahdat, 8—10 fathoms, mud (-/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (^/s). Long. 4—7 mm. Distribution: — Singapore (2—3 fathoms, coral reef, and in shallow water; ^l2 valves, Danish Exp. to Siam, and Sv. Gad). Hong Kong (Sowerby). 93 189 SowERBY states in his diagnosis: "laterales indistincti, " but this is not the case in my specimens, in which the lateral teeth in the right valve are very well developed; the anterior stands close to the cardinal teeth. Tellina fabrefacta, Pilsbry. Tellina fabrefacta, Pilsbry, Proc. Acad. Nat. Sc. Philadelphia, vol. 56, 1904, p. S.'iS, pi. 41, ligs. 11 — 12. — — — Hedley, Proc. Linn. Soc. New South Wales, vol. 31, 19(1(1, p. 178. Between Koh Rin and Cliff Rock, 15 fathoms ('^/2). Long. 5 mm. Distribution: — Singapore, shallow water (long. 5"5 mm.), Sv. Gad; Hirado, Hizen (Japan), Pilsbry; Mast Head Reef (Queensland), Hedley. Tellina (Arcopagia) capsoides, Lam. Tellina capsoides, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 531, No. 44. — éd. 2, VI, 1835, p. 205, No. 44. — Capsoides, — Hanley, Monogr. of the gen. Tellina (Sowerby, Thes. Conchyl., Ij, p. 268, No. 85, pi. 62, fig. 185. — capsoides, — Reeve, Conchol. icon., XVII, Tellina, Sp. 183. — {Tellinella] capsoides, Lamarck, Römer in Martini & Chemnitz, Conchyl. Cabin., X Ud., 4 Abth. p. 48, No. 28, pi. 14, figs. 1—3. — • — — Bertin, Revision d. Tellinides, p. 250, No. 49. — {Arcopagia) — — Tryon, Catalogue of the family Tellinidæ, p. 89, No. 127. The strand off the mangrove at the station on Koh Chang, shallow water (3). Long. 26—36 mm. Distribution: — Andamans, from Goa to Bombay, Karachi, Gulf of Suez (Mac Andrew), Natal coast (Sowerby). — Philippines, Hong Kong, Giabu Lengan (Aru), "Australia", Saint-Pierre, Saint-Francois, Viti Isis. Tellina negrosiensis, V. Bertin, judging from the description, no doubt scarcely differs specifically from the present species. Tellina (Arcopagia) Siamensis, v. Mart. TclUiui [Arcopagia) siamensis, v. Martens, Proc. Zool. Soc. London, 1860, p. 18. — Siamensis, v. Martens, Malacozool. Blätter, 1873, p. 175. Arcopagia siamensis, — V. Bertin, Revision d. Tellinides, p. 326, No. 39. Tellina (Arcopagia) Siamensis, v. Martens, P. Fischer, Moll, de I'lndo Chine, p. 245. — — — — Melvill & Standen, Proc. Zool. Soc. London, 190(), p. 822. — perplexa, Römer (non Hanley), Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 49, No. 29, pi. 14, figs. 4 — 6 (tide E. v. Martens).' Siam (Mr. Mouhot). The Danish Expedition to Siam collected no specimens of this species. ' Malakozoolog. Blätter, 1873, p. 168. Although E.V. Martens in the paper in question states that he thinks Rômer's figure and description of T. perplexa agree with his T. Siamensis and not with "der ächte perple.\a Hani.," yet in "The Journal of the Linnean Society," vol. 21, 1887, p. 215, he refers to the same figure in the list of synonyms under T. perplexa, Hanley. 190 94 Dislribu lion: — Karachi (Melvill & Standen). Pilsbry records thai Fa. Stearns took "a short form" of this species at Japan (Inland Sea). T. capsoides, Lam., T. oslracea, Hani., and T. perplexa, Hani., according to V. Martens, are very closely allied to the present species. Tellina (Arcopagia) elegantissima, Sm. Tellina (Arcopagia) elegantissima, Edü. Smith, Report on the Lamellibranchiata of the Challenger Exped., 1885, p. 105, pi. 4, fig. 3. Koh Lan, 30 fathoms, mud (^'i). Gulf of Rayong, 7—10 fathoms, sand and mud (2). S. of Koh Mak, 5—6 fathoms (2). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (-/s). Same locality, 6 fathoms, mud mixed with sand (^^/a). W. of Koh Kut, 15 fathoms, mud (Va). Koh Kahdat, 1 — 5 fathoms, sand (1). Long. 10 — 18 mm. (long. 18 mm., alt. 15 mm., crass. 9 mm.). Distribution: — Torres Strait. Tellina {Arcopagia) habrotima, Melvill,' from Angrias Bank, Arabian Sea is very closely related to the present species. Tellina (Arcopagia) carnicolor, Hani. Tellina carnicolor, Hanley, Sowehby, Thesaur. Conchyl., I, 1846, p. 2()3, No. 75, pi. 50, fig. 15. — — - Reeve, Conchol. icon., XVll, Tellina, Sp. 126. — (Arcopagia) carnicolor, Hanley, Römeh in MAiiTiM u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 85. Arcopagia carnicolor, Hanley, V. Bertin, Revision d. Telliiiidcs, p. 322, No. 16. Tellina incarnata, Hanley, Proc. Zool. Soc. London, Xll, 1844, p. 68. — Strangei, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 362, No. 206 (fide Edg. A. Smith).- — corbis, Sowerby, Reeve, Conchol. icon., XVll, Tellina, Sp. 127 (fide Eug. A. Smith). N. of Koh Kam, 5 fathoms, gravel (1). Koh Mesan, 15 fathoms, stones ('/a). Between Koh Mesan and Cape Liant, 5—9 fathoms ('/a). W. of Koh Kut, 15 fathoms, mud (21/2). Long. 4—13 mm. (long. 13 mm., alt. 10 mm., crass. 5 mm.). Distribution: — Andamans, Maldive Archip. — Philippines, New Caledonia, New Zealand (T. Strangei). The above measurements indicate that the specimens from the Gulf of Siam (which are not full-grown) are more oblong-ovate in form than is shown by the figures which have hitherto been published. Tellina (Arcopagia) inflata, Chemn. Tellina inflata, Chemnitz, Conchyl. Cabin., VI. 1782, p. 91, pi. 9, tig. 76. — - — Si'ENGLER, Skrivter af Naturh. Selsk., IV, 2 H., 1798, p. 9!), No. 27 (non varr.). ' Memoirs of the Liter. & Philos. Soc. Manchester, vol. 42, 1898, No. 4, p. 34. - The Fauna and Geography of the Maldive and Laccadive Archipelagoes, ed. by ,1. St. Gardiner, 11, p. 627, 1903. Melvill and Sykes have already stated (in Proc. of the Malacolog. Soc. London HI, 1897, p. 47) that: "T. carnicolor Hani, appears to be identical witli ï. eorfcis Sby. and T. Strangei Desh." 95 191 TeUina {Tellinella) inflata, Chemnitz, Edg. Smith, Proc. ZooI. Soc. London, 1891, p. 426, No. 211. — striatala, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 529, No. 33. — éd. 2, VI, p. 201, No. 33. — — — Hanley, Soweuhy, Thés. Conchyl., I, p. 255, No. fil, pi. 61, fig. 175. — — — Reeve, Conchol. icon., vol. XVII, TeUina, Sp. 34. Arcopagia — — Bertin, Révision d. Tellinidés, p. 32(1, No. 9. TeUina hippopoidea, Jonas, Philippi, Abbild, u. Ueschieib. neuer od. wen. gek. Conchy)., I, p. 72 (8), TeUina, pi. 1, fig. 3. Koh Lan, 30 fathoms, mud (^/s). Koh Kram, 30 fathoms (1). S. of Koh Chuen, 30 fathoms, shells (',2). Cape Liant, 9 fathoms, shells (^ a). N. of Koh Kahdat, 4 — 5 fathoms, coarse sand (1). S. of Koh Kahdat, 8-10 fathoms, mud ('/a). Between Koh Kut and Koh Kahdat, 6 — 10 fathoms, shells (-/s). W. of Koh Kut, 15 fathoms, mud (-/a). S. of Koh Mak, 5—6 fathoms (2). Long. 12—30 mm. Distribution: — Singapore (shallow water, Sv. Gad), Nicobars, Andamans, Ceylon, Aden, Red Sea, Suez, Zanzibar, Mauritius. — Philippines, China, Celebes, Java, Port Curtis, New Caledonia. Chemnitz's original specimens of T. inflata (in the Zoological Museum of the University of Copenhagen) are very large and rather thick-valved,' but they exactly agree with Reeve's figure of T. striatula, Lam., and with the specimens from the Gulf of Siam. V. Bertin, who has had an opportunity of consulting Lamarck's original specimens of striatula, in his "Révision" gives both Reeve's and Hanley's (Sowerby) striatula as synonyms of the present species. Römer (in Martini u. Chemnitz, Conchyl. Cabin.) is mistaken with regard to his inflata, Ch., neither his description nor his figures agree with Chemnitz's species;- Bertin also says that Rö.mer is wrong in reporting striatula, Lam., to be young specimens of the West Indian T. fausta, Pult. The specimens from the Gulf of Siani, all of which are rather small and consequently thin-valved, entirely agree with Reeve's figure of striatula. It appears as if the convexity of the valves varies somewhat in this species; thus, in a specimen from the Gulf of Siam, measuring 25 mm. in breadth and 21 mm. in height, the thick- ness is 105 mm., while in an individual from Suez, ^ of the same breadth and height, it is only 7 mm. Tellina languida, Edg. Smith, is very closely related to the present species. TeUina (Arcopagia) pinguis, Hani. TeHina pinguis, Hanlev, Proc. ZooI. Soc. London, XII, 1844, p. 63. — — — Sowerby, Thesaur. Conchyl., I, p. 252, No. 55, pi. 56, fig. 34. — — — Reeve, Conchol. icon., XVU, TeUina, Sp. 172. — Arcopagia) pinguis, Hanley, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Rd., 4 Abth., p. 96. Arcopagia pinguis, Hanley, V. Bertin, Révision d. Tellinidés, p. 322, No. 15. ' Chemnitz's figure is not good and is partially misleading. -' Römer is liard to be understood, when his figure of inßata fpl. 15, figs. 1 — 3) is compared with the figure of striatula by Hanley (pl. 61, fig. 175), which he gives as a synonym; the two figures do not resemble each other in the least. ' In the Zoological Museum of the Universitj' of Copenliagen, received from L. Vaillant, who has determined it as T. truncata, Hani. (Journ. de Conchyl., 1865, p. 121, No. 79). 192 96 N. of Koh Kam, 5 fathoms, gravel (1). Off Koh Kam, 10 fathoms, gravel (1). Koh Kahdat, 1 fathom, sand (1). Long. 11 — 13'5 mm. Distribution:— Philippines, Torres Strait, New Guinea (Brazier), New Caledonia, Viti Isis. The specimens are covered with a thin epidermis which is ornamented with con- centric elevations separated by fairly regular intermediate spaces (about 0.5 — 1 mm.); these elevations show most distinctly towards the ventral side, as the greater part of them is worn off upon the umbones, where they have left only concentric lines, which are, however, distinctly visible. Upon two of the specimens several red rays may be seen; and one of these two agrees almost completely witli H. Adams' Tellina Isseli from the Red Sea (Proc. Zool. Soc. London, 1870, p. 790, pi. 48, fig. 10). A. H. Cooke and Sturany consider T. Savignyi, Ad. (from the Red Sea), to be identical with T. pinguis, Hani.; this I can scarcely believe, but as I have only descriptions and figures to judge from, I cannot make any conclusive statement regarding this point; but it appears to me that T. halaustina L. (and T. Isseli, H. Ad.) are much more closely related to T. pingnis. It is almost impossible to dislinguisli between specimens of balaustina (from Algiers) and of pinguis from the Gulf of Siam. Tellina (Arcopagia) Isseli, H. Ad. Tellina {Arcopayia) hseli, H. Adams, Proc. Zool. Soc. London, 1870, p. 790, pi. 48, fig. 10, Arcopagia Isseli, H. Adams, V. Beiitin, Revision d. Tellinidé.s, p. 324, No. 26. Tellina — — Edg. Smith, Proc. Zool. Soc. London, 1891, p. 395, No. 15. — [Arcopagia) Isseli, H.Adams, Mri.vill and Standen, Proc. Zool. Soc. London, 1906, p 821. Koh Kahdat, 1 fathom, sand (1). Long. 9 mm. Distribution: — Bombay (Melvill, Brit. Mus.), Mekran coast, Gulf of Oman, Persian Gulf (Melvill & Standen), Aden, Red Sea, Gulf of Suez. When Edg. Smith in 1891 published "On a Collection of Marine Shells from Aden"^ he said regarding this species: "I am not aware that it has been found any- where except in the Gulf of Suez." But, as may be seen from the above list of distribution, it has since been recorded as occurring considerably farther towards the east. Tellina (Arcopagia?) nux, Hani. Tellina mix, Hani.ey, Proc. Zool. See. London, XII, 1844, p. 62. — — ~ SowERBY, Thesaurus Conchyl., I, p. 251, No. 54, pi. 56, fig. 33. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 76. — Nux, — Römer in Martini u. Chemnitz, Conchj'l. Cabin., X Bd., 4 Abth., p. 88, No. 53. Arcopagia mix, Hanley, V. Behtin, Revision d. Tellinides, p. 321, No. lU. Tellina — — Dunker, Index moUuscor. mar. Japon., 1882, p. 191. Arcopagia Nux, — Hidalgo, Obra.s malacologicas, I, torn. 11, 1903, p. 151, No. 266. > Proc. Zool. Soc. London, 1891, pp. 390-436. 97 193 Sound of Koh Chang, 5 fathoms, soft clay ('/i). Koh Mak, sandy coast (Vi). Between Koh Chuen and Koh Chang, 15 fathoms, mud (2). Between Koh Kut and Koh Kahdat, 10 fathoms, shells ('/.•). W. of Koh Kut, 30 fathoms, sand and mud (Vi). Long. 6-5—13 mm. (long. 13 mm., alt. 10 mm.). Distribution: — Karachi (Melvill & Standen). — Philippines, Japan, Upolu (Mus. Godeffroy). The figures in Römer's Monograph (pi. 24, figs. 1—3) bear no resemblance whatever to T.niix, Hani.; they undoubtedly represent quite a different species. Tellina (Arcopagia?) casta, Hani. Tellina casta, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 63. — — — SowERBY, Thesaur. Conchyl., I, p. 253, No. 57, pi. 56, fig. 9. — — -- Reeve, Conchol. icon., XVII, Tellina, Sp. 269. — (Arcopagia' casta, Hanley, Römer in Martini u. Chemnitz, Conch}'!. Cabin., X Bd., 4 Abtli., p. 95. Arcopagia casta, Hanley, V. Bertin, Revision d. Tellinidés, p. 323, No. 21. Tellina (?) casta, — Edg. Smith, Lamellibianchiata of the Challenger Exped., p. 109. E. of Koh Chuen, 9-10 fathoms, shells (1). Gulf of Rayong, 7—10 fathoms, sand and mud (3 + '/a). S. of Koh Samit, 20 fathoms, mud (1). Koh Kahdat, 1 — 10 fathoms, mud, sand and clay (5 + ^''/s). W. of Koh Kut, 15 fathoms, mud (2). Long. 5 — 16 mm. Distribution: — Singapore (Hanley; Danish Exp. to Siam, 2 — 3 fathoms, coral-reef (5); Sv. Gad, shallow water), Mergui Archipel. — Torres Strait, Tonga Isis., Upolu (Mus. Godeffroy). The present species is easily distinguishable from forms allied to it, by the left valve being more convex than the right; it is always quite white in colour. The specimens from the Gulf of Siam are more oblong than the figures given by Reeve and SowERBV; the height of an individual, 13 mm. long, is 10 mm. Tellina (Arcopagia?) declivis, Sow. Tellina ilcclivis, Sowerhy, Reeve, Conchol. icon., vol. 17, 1868, Tellina, Sp. 261. Arcopagia declii'is, Sowerry, V. Bertin, Révision d. Tellinidés, p. 324, No. 25. W. of Koh Chang, 30 fathoms ("«). Koh Kahdat, at the strand (^/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells {"h). W. of Kut, 15 fathoms, mud ('/a). Long. 5 — 10 mm. (long. 10 mm., alt. 85 mm.). Distribution unknown. (Singapore, 2 — 3 fathoms, coral-reef (1 right valve), Danish Exp. to Siam). My specimens exactly agree with Sowerby's description and figure; they are easily distinguished from T. pudica, to which species they are most closely allied, by the greater convexity, and by the predominance of the height of the valves in comparison with their length. 11 K 1>. Vi.lnisL Sclsli. Sl;r.. 7. R.eliUc nntiirviilen- 1,. n;, ni:illicni Afcl. V. 3. 25 194 98 Teilina (Arcopagia?) languida, Sm. TelUna{9) languida, Edg. Smith, Report on the Lamellibraiichiata of the Challenger Expedition, 1885, p. no, pi. 4, fig. 8. Between Koh Rin and ClifT Rock, 15 fathoms ('/a). Koh Krani, 30 fathoms (3). Koh Chuen, 30 fathoms ('/a), Gnlf of Rayong, 7 — 10 fathoms, sand and mud ('/a). S. of Koh Samit, 20 fathoms, mud (1). Sound of Koh Chang, 3 fathoms, soft clay ('/a). Around Koh Kahdat, 1 — 10 fathoms, sand, mud, clay, and shells (5 + ''/a). W. of Koh Kut, 15-30 fathoms, mud (2 + Vs). Long. 6—11 mm. (long. 11 mm., alt. 9 mm., crass. 5 mm.). Distribution: — Torres Strait and Flinders Passage (Challenger). The species T". mix, casta, robiista, declivis, languida, piidica, etc., form a natural chain or group, which, on the one hand, cannot be placed entirely in Leach's subgenus Arcopagia, (H. and A. Adams have done this, notwithstanding the fact that the character "posterior side rounded" is wanting in several of the species), but, on the other hand, it shows how much the division into subgenera of tlie genus Tellina needs critical investigation. Several authors (e. g. Récluz' and Römer-) have already attached but little importance to this subgenus Arcopagia. Tellina (Arcopagia?) pudica, Hani. (PI. Ill, Figs. 35-37). .Tellina pudica, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 62. — — — SowERiiY, Thesaurus Conchyl., I, p. 246, No. 46, pi. 56, fig, 7. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 176. — (Arcopagia) pudica, Hani.ev, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 95. — (Peronœa) — — V. Rertin, Révision d. Tellinidés, p. 272, No. 1(13. A great many specimens taken from numerous localities between Koh Chuen and Koh Kong, 3—30 fathoms, mud, clay. Long. 3—95 mm. Distribution: — Philippines, Japan (Allart). The specimens from the Gulf of Slam have a somewhat longer rostrum than that shown in the figures by Hanley and Reeve; this species is characterised bj' being strongly polished, glossy, smooth and milk-white in colour; the umbones are prominent and rounded at their apices, and the whole outline recalls that of a Niiculana or (as Hanley says) of a Neaera. Tellina (Arcopagia?) Smithi n. sp. (PI. Ill, Figs. 38—39). This shell is ovately-triangular in form, very thick-valved, pure white in colour, and somewhat glossy. The anterior end, which is roundly elongated, passes evenlj' into the ventral side, the latter is slightly curving and passes without angle-forma- ' Revue zoologique publ. p. Gucrin-Méncville, 1846, pp. 48 — 55. -' Martini u. Chemnitz, Conchyl. Cabin., X 15d., 4 Abtli., p. 72. 99 195 lion into Ihe somewhat truncated posterior side. The umbo is situated towards the posterior side and the apex bends towards it. The umbo is fairly high and slopes gradually downwards on both sides. The surface is covered with close-set, regularly-arranged, concentric striæ; some of these terminate at the place on the posterior side where they bend upwards, and only every other is continued up- wards to the area which is limited by a small keel. The interior of the valve is pure white; in the right valve (which alone is at hand) the lateral teeth are strongly developed on each side; there are two cardinal teeth, of which the hinder is the larger. The palliai sinus is large and deep, but appears very indistinctly upon the glossy inner surface. Long. 5"5 mm., alt. 5 mm., crass. 3 mm. West of Koh Kut, 30 fathoms, sand, mud. As the left valve is not known I cannot decide with certainty whether this species belongs to the subgenus Arcopagia. I have ventured to associate with the name of the present species that of Mr. Edg. Smith, to whom malacological science is indebted for so many valuable works. Tellina (Merisca) Martensi n. sp. (PI. Ill, iMgs. 40-42). This shell is small, white, rather thick-valved and triangular in outline. The surface is ornamented with more or less close-set, raised, concentric lamellæ, the interspaces are smooth and somewhat glossy. The umbones, which are situated at about the middle of the shell, are pointed and prominent, and slope rather abruptly downwards on both sides. The somewhat swollen anterior end passes gradually, and with rounded outline, into the ventral side which is convex and forms a rather acute angle with the hinder side. The jjosterior part exhibits a slight "Tellina- curvature." The interior of the valves is white and glossy. In the right valve there are two cardinal teeth, and two oblong, strongly developed lateral teeth; in the left valve there are no lateral teeth and of the two cardinal teeth the anterior is the larger. The palliai sinus is large and deep. South of Koh Kut, 17—20 fathoms, mud (Va). (Singapore, 2—3 fathoms, coral- reef; '"l-i). Long. 35 mm., all. 3 mm., crass. 2 mm. This little characteristic Tellina-form must be referred to Dall's section Merisca of the subgenus Arcopagia; it somewhat resembles the much larger T. (Merisca) crystallina, Wood, ' from South Carolina, but that species is longer, and has a more decided rostrum. The specimens at hand show that the species varies considerably in regard to form and the density and height of the lamellæ. I have named this species aller the late Professor Ed. v. Martens, the first zoologist who gave us a fauna of the Mollusca of Siam, and to whom malacological science is indebted for many profound and valuable papers and works. ' Proceed. Unit. Stat. Nat. Mus., vol. 23, 1>)00, p. ;ni, pi. 2, fig. 10. 25* 196 100 Teilina (Quadrans) gargadia L. Tcllina Gargadki, Linné, Syst. Nat., ed. X, 1758, p. (>74, No. 33. - ed. XII, p. 1116, No. 44. — Mus. Ludov. Ulr., 1704, p. 476, No. lü. — — — Spengler, Skrivter af Naturliist. Selskabet, IV, 2 H., 17'J8, p. 86, No. 14. — — — Chemnitz, Conchyl. Cabin., VI, p. 83, pi. 8, figs. 63 — 64. — gargadia, — Hanley in Sowekby, Thesaur. Conchyl., I, p. 263, No. 76, pi. 61, fig. 156; pi. 62, fig. 181. _ — — Reeve, Conchol. icon., XVII, TcUina, Sp, 84. — Gargadia, — Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 38, No. 21, pi. 2, figs. 2—4; pi. 11, figs. 8-10. — gargadia, — V. Behtin, Revision d. Tellinidcs, p. 266, No. 87. N. of Koh Kahdat, 4—5 fathoms, coarse sand ('/a). Koh Kahdal, 1 fathom, sand (^/a). Between Koh Riot and Koh Mesan, 3 — 5 fathoms, sand ('/a). Long. 10—30 mm. 1) long. 30 mm., alt. 225 mm. 2) — 25 mm., — 18-5 mm. Distribution: — Nicobars, Ceylon, Seychelles, Zanzibar. — Philippines, Baljan, Mast Head Reef (Queensland), New Caledonia, Pelew Isls. This species varies considerably both in form and in sculpture. The specimens from the Gulf of Siam are all rather small, with slightly prominent sculpture and, as the above measurements show, of ovately-oblong form; they come nearest to Hanley's T. inaeqiialis, but judging from the figures and descriptions I cannot see that that species is anything but a form of gargadia, to which species I have therefore referred my specimens. Hidalgo' arrived at the same conclusion, when treating the specimens from the Philippines; he regards T. inaeqiialis, Hani., to be synonymous with T. gargadia L. Tellina (Quadrans) minor, V. Berlin. re;;i;ia minor, V. Behtin, Revision d. Tellinidcs, 1878, p. 267, No. 9U, pi. 9, lig. 5. Between Koh Riot and Koh Mesan, 5 fathoms, sand (■'/s). Between Koh Mesan and Cape Liant, 5—9 fathoms ('/a). Koh Kahdat, 1 fathom, sand (1). W. of Koh Kut, 15 fathoms, mud ('/-■). Long. 5—9 mm. (long. 9 mm., alt. 6-5 mm., crass. 35 mm.). Distribution:— New Caledonia (Bertin). Tellina (Tellinides) carinata, Spcngl. Tellina tennis oualis, Chemnitz, Conchyl. Cabin., VI, 1782, p. 97, j)!. 10, fig. 87. — carinata, Spengler, Skrivter af Naturhistorie-Selskabet, IV, 2 H., 1798, p. llö. — ohlonga, Gmelin, Linné, Syst. Nat., ed. XIII, 179Ü, p. 3234, No 29. Tellinides emarginatus, Sowerby, A Catalogue of the Shells in the Collection of the Earl of Tankerville, 1825, Appendi.x, p. Ill, No. 199. Tellina {Tellinides) emarginata, Sowerby, Hanley, Monogr. of the gen. Tellina. (Sowerhv, Thes. Conchyl., I) p. 290, No. 130, pi. 57, fig. 70. ' J. G. Hidalgo, Obras malacologicas, I, Tom. II, 1903, p. 122. 101 197 TcUiiHt emanjinata, Sowkhhy, Reeve, Conchol. icon., XVII, Tellina, Sp. 99. — iTellinides) emarginata, Sowerby, Kömkk in Martini u. Chemnitz, Concliyl Cabin,, X Ud , 4 Abtli., p. 177, No. 105, pi. 36. figs. 1—3. — (Homala) — — V. Bertin, Revision d. Tellinidés, p. 291, No. 182. Between Koh Rin and Cliff Rock, 15 fathoms (3). Gulf of Rayong, 7—10 fathoms, sand and mud (Va). S. of Koh Cliuen, 30 fathoms, shells (1). Koh Kahdal, 10 fathoms (several quite young individuals). Long. 7—27 mm. Distribution:— Singapore, Mergui Archip., Bombay. — Torres Strait. As Spengler's original specimens of T.carinala are in the Zoological Museum of the University of Copenhagen, it has been possible for me to verify the fact that Sowekby's species emarginata is synonymous with the present species. Sowerby's specific name must therefore give place to that given by Spengler, which has the priority. Gmelin's name oblonga (from 1790) has not the priority, because Chemnitz, in 1782, mentions Spengler's manuscript-name carinata, which Spengler himself afterwards published. The native land of the species has been very erroneously recorded; Spengler records the coast of Guinea, Chemnitz and Salis Marschlins' the European Seas, and Sowerby Brazil, all of which localities are undoubtedly wrong. Tellina (Tellinides) psammotella, Lam. Tellina psammotella, Lamarck, Hist. nat. d. aniin. sans veitcbres, V, 1818, p. 528, No. 30. — éd. 2, VI, 1835, p. 199, No. 30. — Psammotella, — Hanlev, Descript. Catal. of recent biv. shells, p. 65, pi. 14, tig. 6. — — — Hanlev in Soweruv, Tliesaur. Conchyl., I, p. 290, No. 129, pi. 60, lig. 134. — — — Reeve, Conchol. icon , XVIl, Tellina, Sp. 71. — (Tellinides) Psammotella, Lamarck, Römer in Martini u. Chemnitz, Conchyl. Cabin, X Lid., 4 Abth., p. 176, No. 104, pi. 35, figs. 12—14. Macoma psammotella, Lamarck, V. Bertin, Revision d. Tellinides, p. 337, No. 11. — Psammotella, — Hidalgo, Estud. prelim, sobre la fauna inalacol. de las Islas Kilipinas, I, 1903, p. 160, No. 280. Sound of Koh Chang, 5 fathoms, soft clay {''I2). Long. 11 — 16 mm. (long. 16 mm., alt. 9 mm.). Distribution: — Singapore, shallow water (Danish Exp. to Siam, and Sv. Gad). Cebu (Philippines, Quadras). Lamarck states that the interior of his specimens are ornamented with orange, red, or purple rays, but this is not the case with the individuals which I have before me, all of which are interiorly (and exteriorly) uniform in colour, pale-red (flesh-coloured). As regards the lateral teeth, Hanley (Thesaur. Conchyl.) observes, "lateral tooth distinct, approximated," while Reeve, in his diagnosis, says, "dentibus lateralibus nuUis." V. Bertin and Hidalgo, on the basis of the latter statement, without investigating the subject more closely, have referred the species to Macoma. ' Reisen in verseh. Provinzen d. Königr. Neapel, I, 1793, p. 384. No. 108. 198 102 In reality the lateral teeth (ami the hinge as a whole) are developed as in Tellina emarginata, Sow., to which species also, T. psammotella comes nearest in external appearance. Tellina (Tellinides) vestalis, Hani. Tellina vcstalis, Hani.ky, Proc. Zool. Soc. London, XII, 1844, p. 141. — — — Monograph of the gen. Tellina (Soweriiy, Thesau'r. Concliyl., I), p. 291, No. I'i'I, pi. 57, fig. 67. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 230. — ( Tellinides) vestalis, Hani.ky, Römer in Mahtini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 174, No. 103, pi. 35, figs. 9-11. S. of Koh Kahdat, 8—10 fathoms, mud (1). Between Koh Kahdat and Koh Kut, 6 fathoms, clay mixed with sand (I'/s). W. of Koh Kut, 15 fathoms, mud (Va). Long. 9—28 mm. Dislrihution: — Karachi (Melvill & Standen), Mauritius. — Philippines. I very much doubt whether Römer (Ioc. cit.) had the true T. vestalis, Hani, before him ; neither his figure nor his description agrees with Hanley's species. Tellina (Tellinides) ovalis, Sow. Tellinides ovalis, G. B. Soweruy, Catalogue of the Shells in the Collect, of the Earl of Tankerville, 1825, Append., p. Ill, No. 198. — — — Hanlky, Catal. of rec. biv. shells, p. 73, pi. 13, fig. 56. Tellina (Tellinides) ovalis, Sowhrisy, Haniæv, Thesaur. Conchyl., I, p. 296, No. 142, pi. 60, fig. 147. — ovalis, SowERBY, Reeve, Conchol. icon., XVII, Tellina, Sp. 105. — — — LiscHKE, Japan. Meeres-Conchyl., Ill, p. 94. — — — Bertin, Revision d. Tellinides, 1878, p. 284, No. 140. — — — Dunker, Index moll. mar. Japon., 1882, p. 190. — — — Hidalgo, iMoIusc. mar. de las Isl. Filiplnas, 1903, p. 134, No. 238. Solen ex albido radiatun, Chemnitz, Conchyl. Cabin., VI, 1782, p. 71, pi. 7, figs. 57— 58. — slriatus, Gmelin, Syst. Nat., ed. XIII, p. 3227, No. 19. Tellina tridentata, Anton, Archiv f. Naturg., Ill, 1837, Bd. I, p. 283. — gratiosa, Römer in Martini u. Chemnitz, Conchyl. Cabin., X lid., 4 Abtli., p. 170, No. 100, pi. 34 figs. 10—12. OtT Koh Kam, 10 fathoms, gravel (Vs). Long. 37 mm., alt. 235 mm. Distribution: — Nicobars, Karachi, Persian Gulf, Gulf of Suez, Red Sea (fossil, V. Bertin), Madagascar. — Philippines, Moluccas, Japan. Tellina (Moerella) semen, Hani. Tellina semen, Hanley, Proc. Zool. Soc. Loudon, XII, 1844, p. 164. — — — Sowerry, Thesaur. Conchyl., I, p. 249, No. 51, pi. 56, fig. 8. — (Arcopagia) Semen, Hani.ky, Römer in Martini u. Chemnitz, Conchyl. Cabhi., X Bd., 4 Al)tli., p. 95. — (Homala) semen, — V. Bertin, Revision d. Tellinides, p. 303, No. 268. — semen, Hanley, Edg. Smith, Report on the Zool. Collections made in the Indo-Pacific Ocean during the voyage of "Alert," 1884, p. 99. — (?) semen, Hanley, Edg. Smith, Rep. on the Lamellibranchiata of the Challenger Exped., p. 111. — (Moera) semen, Hanley, Melvill & Standen, Proc. Zool. Soc. London, 1906, p. 821. 103 199 OiT Koh Kam, 10 fathoms, gravel ('/:;). Between Koh Mesan and Cape Liant, 5—9 fathoms (Vs). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (^/a). Long. 6—9 mm. (long. 9 mm., ait. 7 mm.). Distribution:— Karachi, Mekran coast, Persian Gulf, Durban.' — Philip- pines, Torres Strait, Flinders Passage, Viti Isis. Sowerby's figure in Reeve's "Conchol. icon." (pi. 41, sp. 232), which Edg. Smith regards as "bad," agrees fairlj' well with the individuals from the Gulf of Siam, and although it is not perfectly typical, yet it can be recognised ; besides, it agrees well with Sowerby's original figure in "Thesaurus Conchyliorum." Tellina (Moerella) semitorta, Sow. (PI. Ill, Figs. 43-46). Tellina scmilorla, Sowerby,' Reeve, Conchol. icon., XVII, 18()7, Tellina, Sp. 221. — (Mœra) semitorta, Sowerby, Angas, Proc. Zool. Soc. London, 1867, p. 919. — if) — — Edg. Smith, Report on the Laniellibranchiatn of the Challenger E.\ped., p. 111. — (Donacilla) semitorta, Sowerby, Mei.vili. & Standen, Journ. Linn. Soc. Zool., XXVII, p. 201. — — — — V. Bertin, Revision d. Tellinidés, p. 263, No. 81. Between Koh Bin and Cliff Bock, 15 fathoms (V-i). Koh Kram, 30 fathoms (V2). N. of Koh Kam, 5 fathoms, gravel (4 + 'Va). Ofi" Koh Kam, 10 fathoms, gravel ('/a). Between Koh Mesan and Cape Liant, 5—9 fathoms (12). North side of Koh Mesan, 10—15 fathoms, stones (^/s). Gulf of Rayong, 7 — 10 fathoms, sand and mud (1 + Va). Between Koh Kut and Koh Kahdat, 10 fathoms, shells ('/2). W. of Koh Kut, 15—30 fathoms, mud (1 + 2/.,) Koh Kahdat, 1—5 fathoms, sand (2 + %). Long. 2-5 12 mm. Distribution: — Singapore (low water, Sv. Gad). Torres Strait, Port Jackson (Sydney), Watson's Bay (New South Wales). This species varies considerably in form; on PI. Ill, Figs. 43—46, I have given several instances of this;" the sculpture, also, is very variable. Thus, for in- stance, the concentric striation may be more or less close-set; and the place where the less close-set, posterior striation meets the rest of the valve-sculpture is often situated very far back, while in other specimens it may be at about the middle of the valve; and often the more prominent lamellar sculpture upon the posterior end has al- most entirely disappeared, and the sculpture is nearly uniform over the whole surface of the valve. Nor is the striation, as a rule, the same on both valves. The tortuosity of the posterior end of the valves, mentioned by Edg. Smith (loc. cit., p. 112), is in one specimen directed towards the right, and in another towards the left. Smith's statement that: "the anterior lateral teeth and the plate supporting the ligament are tinged with pale-red," is not found in the specimens from the Gulf ' Edg. Smith, Proc. Malacolog. Soc. London, vol. 5, p. 400. - Edg. Smith's criticism of Sowerby's figure in Reeve's "Conchol. icon." is unjustified; several specimens from the Gulf of Siam have the form shown in Sowerby's figure. 200 104 of Siam; only in one individual is there any indication of this tinge of colour; in that specimen the red colour radiates downwards over the valves, both within and without, but in all the others the shells are quite white, with a thin yellow epidermis, which is often quite worn off, or is present only in remnants. Tellina (Moerella) Berghi n. sp. (PI. Ill, Figs. 47-49). This shell is oblong-ovate, white and rather thick-valved; the umbones are situated towards the posterior end; a sliglit indication of a keel extends from the umbo obliquely down towards the posterior angle of the ventral side, which curves gently like the anterior and posterior sides, into which it passes without angle- formation. The surface is sculptured with close-set, parallel, raised, concentric striæ; on the posterior side some of these striæ, for want of« space, do not extend quite to the hinder upper margin, but otherwise all the striæ extend entirely round the valve. These raised concentric striæ, and also the spaces between them, are orna- mented with very fine, close-set, concentric lines, which are again crossed by fine radiating grooves which become more distinct the nearer they approach the ventral side; all of which produces, if seen under the lens, an exceedingly beautiful and fine beadlike sculpture, resembling fine weaving. The interior of the valves is white and glossy. In the right valve there are two well developed, oblong lateral teeth and two cardinal teeth, of which the hinder is bifid and considerably larger than the anterior. Long. 7 mm., alt. 5 mm., crass. 3 mm. The strand of Koh Kahdat (»/2). This species belongs to the group T. semen, Hani., T. semitorta, Sowb., T. mira- cylliuiv, Melv., etc., but its characteristic and beautiful sculpture easily distinguishes it from nearly-allied species. Unfortunately only one right valve was obtained. I have dedicated this species to the late Professor Run. Bergh, the eminent author of so many vahiable works on Mollusca, who has also described the Nudibranchs of the Gulf of Siam, and to whom I personally owe thanks for much encourage- ment and kindness. Tellina (Moerella) tenuilirata. Sow. Tellina tenuilirata, Sowf.rby, Reeve, Conchol. icon., XVII, 1867, Tellina, Sp. 21!) (non 7". tenuilirata^ Sowerby, Conchol. icon., Sp. 253 = T. seniilaevis, v. Martens). — — — Angas, Proc. Zool. Soc. London, 1867, p. 919, No. 48. ' — — — Edg. Smith, Rep. Lamellibianchiata of tlie Challenger Exped., p. lOfi. ^ (Homala) tenuilirata, Sowekby, V. Rehtin, Révision d. Tellinidés, p. 299, No. 234. — tenuilirata, Sowerby, Pritchahd & Gatlii-k, Proceed. Roj'. Soc. Victoria, XVI, 191)3. p. 116. Koh Kram, 30 fathoms (^/2). Between Koh Mesan and Cape Liant, 5 — 9 fathoms, sand ('/a). N. of Koh Kam, 5 fathoms, gravel ('/s). 01Ï Koh Kram, 10 fathoms, gravel (^a). Gulf of Rayong, 7—10 fathoms, sand, mud (1). Koh Kahdat, 1—5 fathoms, sand ("'/:;). 105 2Ô1 Long. 4 — 11 mm. Distribution: — Flinders Passage (Torres Str.); Port Kembla and off Cape Three Points (New South Wales, Hedley); Port Jackson, Sydney; Frankston, Port Philip (Victoria); Levuka, Viti Isis. Teilina (Moerella) obtusalis, Desh. Tellinci obtusalis, Deshayes, Proc. Zool. Soc. London, 1854, p. 355, No. 176. — — — Reeve, Conchol. icon., XVII, 18(i8, TeUina, Sp. 281. — — — Edg. Smith in: Report Zool. Collect, made during the Voyage of H. M. S. "Alert," 1884, p. 99. — iHomala) obtusalis, Deshayes, V. Bertin, Revision d. Tellinidés, p. 298, No. 231. — Malaccana, Sowerby-, Reeve, Conchol. icon., XVII, 1867, Tellina, Sp. 125. — {Donacilla) Malaccana, Sowerby, V. Bertin, Revision d. Tellinidés, p. 262, No. 80. Koh Kahdat, on the strand (-/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (^/s). Long. 7"5 — 10 mm. Distribution: — Malacca, Karachi (Melvill & Standen). — Viti Isis. (Brit. Mus.). As the specimens are in a bad state of preservation the determination is some- what uncertain. Note. Tellina (Moerella) compacta, Edg. Smith, has been taken by Sv. Gad (a single left valve, worn) at Singapore, in shallow water. Tellina (Angulus) lux, Hani. Tellina lux, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 140. — — — Sowerby, Thesaur. Conchyl., 1, p. 288, No. 126, pi. 57, fig. 71. — — — Reeve, Conchol. icon., vol. XVII, Tellina, Sp. 286. — (Angulus) Lux, Hanley, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 159. — — lux, — Edg. Smith, Report on the Lamellibranchiata of the Challenger E.\ped., p. 102. — {Homala] — — V. Bertin, Revision d. Tellinidés, p. 296, No. 217. W. of Koh Kut, 30 fathoms, sand and mud (1 + ^'2). Long. 14—16 mm., alt. 9—10 mm. Distribution: — Persian Gulf, Gulf of Suez (Mac Andrew). — Philippines, Torres Strait, Arafura Sea. The specimens from the Gulf of Siam are pale-red in colour. Tellina (Angulus) corbuloides, Hani. Tellina Corbuloides, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 70. — — — Sowerby, Thesaur. Conchyl., I, p. 280, No. 108, pi. 57, figs. 50, 57. corbuloides, — Reeve, Conchol. icon., XVII, Tellina. Sp. 70. — — — V. Bertin, Révison d. Tellinidés, p. 280, No. 129. — — — Hidalgo, Moluscos mar. de las Isl. Filipinas, 1903, p. 129, No. 233. D. K. D. Viilensk. Sclsk. Skr., 7. Række. n.nturviileii5k. og miilhem. Afd. V. 3. 26 202 106 The coast of Lem Ngob (1). Long. 13-5 mm. Distribution: — Philippines, Borneo. Tiie form which Römer figures and describes (Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 155, No. 95, pi. 33, figs. 8—10) under the name of T. corbu- loides is not Hanley's species. Tellina (Angulus) iridescens, Bens. Sanguinolaria iridescens, W.H.Benson, Annals and Magaz. of Nat. Hist., vol.9, 1842, p. 490. Tellina — — Philippi, Abbild, u. Beschreib., Il, p. 23 (91), No. 5, pi. 4, fig. 5. — — — Hanley in SowERBY, Thesaur. Conchyl., 1, p. 286. No. 122, pi. 58, fig. 88. — {Angulns) — — Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 134, No. 77, pi. 29, figs. 15— 17. — — — Reeve, Conchol. icon., vol. XVII, Tellina, Sp. 129 and 189. — — — LiscHKE, Japan. Meeres-Conchyl., Ill, 1874, p. 93. — {Fabulina) — — V. Bertin, Revision d. Tellinides, p. 276, No. 112. — — — Hidalgo, Moluscos marin, de las Isl. Filipinas, 1903, p. 126, No. 228. — carnea, Philippi, Zeitsch. f. Malakozool., 1844, p. 162, No. 3. The sound of Koh Chang, 5 fathoms, soft clay ('/2). Long. 14—20 mm. (long. 20 mm., alt. 11-5 mm.). Distribution: — Karachi (Melvill & Standen). — Philippines, China, South Japan, Torres Strait. The individuals from Koh Chang exactly agree with some specimens in the Zoological Museum in Copenhagen from Chusan (forwarded by Th. Cantor). Reeve's figures give the characteristics of the species most accurately. Tellina (Angulus) iridella, Mart. Tellina iridella, E. v. Martens, Annals and Magaz. of Nat. Hist., 3 Ser., vol. XVI, 1865, p. 431, No. 9. — [Macoma] iridella, E. v. Martens, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 256, No. 160, pi. 49, figs. 4—6. — iridella, E. v. Martens, Lischke, Japan. Meeres-Conchyl., II, p. 114, pi. 10, figs. 8— 9. Macoma — — V. Bertin, Révision d. Tellinides, p. 350, No. 55. W. of Koh Kut, 15 fathoms, mud (1). Long. 13 mm., alt. 8 mm., crass. 35 mm. Distribution: — Japan, Loo-Choo Isls. My specimen, like that of Lischke, has in the right valve a lateral tooth in front of the cardinal teeth. The species must therefore be referred to the subgenus Angulus, and not to Macoma, as previous authors have done. Tellina (Angulus) unifasciata, Sow. Tellina unifasciata, Sowerbv, Reeve, Conchol. icon., XVII, 1867, Tellina, Sp. 156. — (Angulus) unifasciata, Sowerby, Angas, Proc. Zool. Soc. London, 1867, p. 919, No. 49. — (Fabulina) — — V. Bertin, Révision d. Tellinides, p. 281, No. 130. 107 203 W. of Koh Kut, 15 fathoms, mud ('/•.>). Between Koh Kut and Koh Katidat, 10 fathoms, shells (Vs). Long. 9—10 mm. D islrihution: — Arabian Sea (Mklvii.l & Standen), Gulf of Suez (Cooke), Seychelles (Brit. Mus.). — Port Jackson (Angas). The specimen from the collection of Petit de la Saussaye mentioned by V. Bertin, which is recorded with doubt from Florida, should unquestionably be omitted from the literature. Tellina (Angulus) dispar, Conr. Tellina dispar, Conbad, Journ. Acad. Nat. Sc. Philadelphia, VII, part 2, 1837, p. 259, No. 4. — —, - Hanley in SowERBY, Thesaur. Conchyl., I, p. 306, No. 164, pi. 59, figs. 108, 113-14. — — — RÖMER in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 148. No. 90, pi. 32, figs. 7—9. — — — SowERBY in Reeve, Conchol. icon., XVII, Tellina, Sp. 10. — — — E. V. Martens, Donum Bismarckianum, 1871, p. 62. — {Fabulina) dispar, Conrad, V. Bertin, Révision d. Tellinidés, p. 277, No. 117. — dispar, Conrad, Hidalgo, Fauna malacol. de 1. Isl. Filipinas, II, 1903, p. 126, No. 229. Koh Kahdat, 1 fathom, corals (1). Long. 15 mm. Distribution; — Maldive Isis., Mauritius, Querimba Isis. (Mozambique), Natal. — Philippines, Port Curtis and Moreton Bay (Queensland), Marianne Isis., New Caledonia, Lifu, Samoa Isis., Tahiti, Funafuti Atoll, Sandwich Isis. The records of the occurrence of this species along the coast of California (Tryon and Jay) and in the Strait of Magelhaens (Bertin) are undoubtedly due to erroneous determination of allied species. Tellina (Angulus?) rhomboides, Quoy & Gaim. Tellina rhomboides, Quoy et Gaimabd, Voyage de l'Astrolabe, Zoologie, II, 1833, p. 502, pi. 81, figs. 4 — 7. — Rhomboides, — Hanley in Sowerby, Thesaur. Conchyl., I, p. 304, No. 162, pi. 58, figs. 92, 96 and 97. — rhomboides, — Reeve, Conchol. icon., XVII, Tellina, Sp. 114. — (Angulus) rhomboides, Quoy et Gaimabd, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 144, No. 87, pi. 31, figs. 14— 17. — [Fabulina) — — Bertin, Revision d. Tellinidés, p. 279, No. 123. — [Angulus?) — — Edg. Smith, Rep. on the Lamellibranchiata of the Chal- lenger Exped., p. 103. — clathrata, (Quoy) Deshayes, Lamarck, Hist. nat. d. anim. s. vert., 2 éd., 1835, VI, p. 208, No. 57. — — — — Hanley, Catal. of rec. biv. shells, p. 65, pi. 14, fig. 12. — compta, Gould, Wilkes' Explor. Exped., vol. XII, p. 406, Atlas fig. 575. — Otia Conchol., 1862, p. 79. — lauta, — loc. cit., p. 408, Atlas fig. 514. — Otia Conchol., p. 79. — silicula, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 363, No. 209. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 278. — cascus, Sowerby, — — — — Sp. 115. — texturata, — — — — — pL 41, Sp. 233 ; pi. 45, fig. 233 b. — reticulata, — — — — — Sp. 252. 26* 204 108 Tetlina {Peronœa) pura, H.Adams, Proc. Zool. Soc. London, 1870, p. 789, pi. 48, fig. 6. — — erythræensis, H. Adams, Proc. Zool. Soc. London, 1870, p. 790, pi. 48, fig. 8. — — lactea, H.Adams, Proc. Zool. Soc. London, 1870, p. 790 (fide A. H. Cooke). — subrosea, Römer (non Hanlky), Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., pi. 32, figs. 14-16 (fide Hidalgo). — bifaria, Baird, Brenchley's Cruise of the Curaçoa, 1873, p. 451, pi. 41, fig. 13. Koh Kahdat, 1 fathom, sand (2). N. of Koh Kahdat, 4—5 fathoms, sand ('/2). S. of Koh Mak, 5—6 fathoms (1). Long. 13 — 18 mm. (long. 18 mm., alt. 10 mm., crass. 55 mm.). Distribution: — Minikoi (Laccadive Archip.), Red Sea, Suez, Madagascar, Mauritius, Durban (Edg. Smith). — Philippines, Gulf of Jedo, Timor, Keeling Isls., New Guinea, Marianne Isls., New Hebrides, New Caledonia, New Zealand, Cape York (North Australia), Viti Isls., Funafuti (Ellice Isls.), Lifu, Upolu, Paumotu Isls. All the specimens from the Gulf of Siam agree most closely with Hanley's figure (pi. 58, fig. 96). Note. When Ed. v. Martens records (Malakozoolog. Blätter, vol.21, 1873, p. 176) that Tellina (Scissula) virgo, Hani., was taken "Am Eingang des Golfs von Siam, 8° 29' Nordbreite, 16 Faden," it is certainly due to erroneous determination. According to Dall (Synopsis of the family Tellinidæ, 1900, p. 304) the species occurs from "Gulf of California, la Paz, to Chiriqui." Also Hanley's original specimens are recorded from Chiriqui, West Columbia. Tellina (Peronaea) cygnus, Hani. Tellina cggnus, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 144. _ _ _ SowERBY, Thesaur. Conchyl., I, p. 310, No. 175, pi. 59, fig. 122. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 157. — (Peronœa) cygnus, Hanley, V. Bertin, Révision d. Tellinidcs, p. 271, No. 100. NW. of Koh si Chang, 10 fathoms, mud (Vs). W. of Koh Chuen, soft clay and mud (2/2). Gulf of Rayong, 7 — 10 fathoms, mud (»/s). S. of Koh Samit, 20 fathoms, mud (''/2). S. of Koh Tulu, 10 fathoms, mud mixed with sand ij'l-i). Koh Chang, 3—5 fathoms, soft clay (many specimens). W. of Koh Chang, 20 fathoms, mud (V2). S. of Koh Bidang, 9 fathoms, mud (1/2). S. of Koh Mak, 5—6 fathoms ('/a). W. of Koh Kut, 15-30 fathoms, mud (*/2). Around Koh Kahdat and Koh Kut, 6—10 fathoms, clay mixed with sand, and mud (many specimens). Around Koh Kong, 8—15 fathoms, mud (7). Long. 5 — 16 mm. Distribution: — Philippines, China, New Caledonia. Tellina (Peronaea) micans, Hani. Tellina micans, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 72. — — — Monogr. of the gen. Tellina (Sowerby, Thesaur. Conchyl., 1), p. 309, No. 170, pi. 59, fig. 106. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 130. — [Peronaea] micans, Hani-ey, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 120, No, 71, pi. 28, figs. 5— 7. 109 205 Tellina tlJomala] micans, Hanlev, Bertin, Revision d. Tellinidés, p. 297, No. 222. I'sammohia micttns, Hanley, Edg. Smith, Ann. and Magaz. Nat. Hist., 7 Ser.. XVIII, 190(), p. 2()0. Tellina depauperata, v. Martens, Ann. and Magaz. of Nat. Hist., 3 Ser., vol. lU, 18(1.'), p. 429, No. 4. — — — Römer in Martini u. Chemnitz, Conehyl. Cabin., X Bd., 4 Abth., p. 254, No. l.'iS, pi. 49, figs. 1-3. S. of Koh Samit, 20 fathoms, mud (14). W. of Koh Chang, 20 falhoms, mud (1). Sound of Koh Chang, 3 — 5 fathoms, soft clay C^/ä dead specimens). Koh Kahdat (fragment). Long. 11—29 mm. Distribution: — Persian Gulf (Edg. Smith), Mekran coast (Melvill & Standen), Aden (Shopland). — Philippines. Edg. Smith (loc. cit.) thinks that the present species "on account of the absence of lateral teeth and the oblique sculpture" must be referred to Psammobia, but I am convinced that he is wrong in this; the absence of the lateral teeth being typical of the subgenus Peronaea, and the oblique sculpture being found in so many other species of Tellina. Tellina (Metis) coarctata, Phil. Tellina coarctata, R. A. Philippi, Zeitsehrift f. Malakozool., 1845, p. 151, No. 11. — lacimosa, (non Chemnitz), Hanlev in Sowerbv, Thesaur. Conchy!., I, p. 322, No. 197. pi. 65, fig. 252. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 25. — (Metis] lacunosa, (non Chemnitz), Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 4 Abth., p. 201, No. 120, pi. 38, figs. 10-12. North of Koh Kam, 5 fathoms, gravel (Va). Long. 49 mm. Distribution: — China. 1 have specimens at hand labelled "Algoa Bay" and "Senegal." It seems to me that Philippi has good reason for doubting whether Chemnitz's lacunosa "from Guinea" is identical with the ''lacunosa from China" of later authors; therefore, I have adopted his name coarctata for the latter form. Unfortunately, it is very probable that Chemnitz's original specimen of lacunosa no longer exists, at any rate it is not to be found in the Zoological Museum of the University of Copen- hagen, so actual comparison is impossible; but as Chemnitz's figure and description present many characteristic points which are not to be found in coarctata, 1 think we have here two distinct species. It is no doubt due to a mistake that Spengler' gives "East India" as the locality of his T. ephippium. His original specimens are in the Zoological Museum of the University of Copenhagen, but on the label, in his own handwriting, no locality is given. On comparing Spengler's original specimens of T. ephippium with specimens of Say's intastriata (= T. Gruneri, Phil.^) it is seen that these species are absolutely identical, and as Spengler's name has the priority. Say's intastriata and Philippi's Gruneri should consequently be regarded only as synonyms of ' Skrivter af Naturhistorie-Selskabet, 4 Bind, 2 Hefte, 1798, p. 104. 2 From Florida Keys, St. Anna (east coast of Mexico) and from many different localities in the Lesser Antilles, especially the Danish West Indies. 206 no T. ephippiiim, Spengler. Philippi^ had already some idea of this when he estahlished his T. Gruneri. Reeve's figure, Sp. Ill, of T. ephippiiim, Spglr., exactly corresponds with Spengler's original specimens and with T. Gruneri, therefore I fail to see the reason why Römer finds that Hanley's figure of ephippiiim is "himmelweit ver- schieden" from Reeve's figure; they are almost identical if the figures are placed in the same position. Tellina (Macoma) Candida, Lam. Psammotœa Candida, Lam\hck, Hist. nat. d. anim. s. vert.,V, 1818, p 517, No. 6. — éd. 2, VI, 1835, p. 183, No. 6. Tellina sericina, Jonas, Phii.ii'I'I, Abbild, u. beschreib, neuer od. wen. gek. Conchyl., I, (18431, p. 71, No. 1, Teilina, pl. 1, fig. 1. — Galatœa, Hanley in Sowerby, Thesaur. Conchyl , I, p. 301, No. 154, pl. 04, fig. 223 (non T. galatæa, Lamarck). — Galalhæa, Reeve, Conchol. icon., XVII, Tellina, Sp. 102 (non T. galatæa, Lamarck). — \Macoma) Galatea, Römer in Martini u. Chemnitz, Concliyl. Cabin., X Bd., 4 Abtb., p. 24il, No. 154, pl. 47, figs. 7 — 9 (non T. galatœa, Lamarckl. Macoma Candida, Lamarck, V. Bertin, Révision d. Tellinidés, p. 342, No. 27. Coast of Lem Ngob, low tide (Vs). Sound of Koh Chang, 3—5 fathoms, soft clay (1 + 21/3). W. of Koh Chang, 30 fathoms (1). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (^/s). W. of Koh Kut, 30 fathoms, sand and mud (V2). Long. 10 — 46 mm. Distribution: — "Am Eingang d. Golfs v. Siam in 16 Faden" (E. v. Martens). Philippines, China, Japan, Moluccas, Java, Timor, Australia. All the specimens from the Gulf of Siam are entirely destitute of the granu- lated sculpture characteristic of galatæa (Hanley); at first I determined them as belonging to a form near to T. Candida; but on account of the confusion which has prevailed within this group (and which V. Beutin has but partially dispersed) I asked Mr. Edg. Smith to be kind enough to compare them for me, and he deter- mined them as M. Candida, Lam., "in which the peculiar granose epidermis is ob- solete. T. arafiirensis, Smith, is dilTerent in form." Hanley (Proc. Zool. Soc. London, XII, 1844, p. 147) has described, under the name of T. Diana, a form of his galatæa with a smooth surface, and it must undoubtedly be this varietj' to which the specimens from the Gulf of Siam are most closely allied. Tellina (Macoma) papyracea, Spengl. (Pl. Ill, Figs. 50—52). Tellina papyracea, Spengler, Skrivter af Naturhistorie-Selskabet, 4de Bd., 2det Hefte, 1798, p. 98, No. 25. ^ — gubernaculum, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 142. — — — Sowerby, Thesaur. Conchyl., I, p. 325, No. 201, pl. G2, fig. 186. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 181. — (Macoma) Gubernaculum, Hanley-, Römer in Martini u. Chemnitz, Concliyl. Cabin., X Bd., 4 Abth., p. 247, No. 152, pl. 47, figs. 1—3. Macoma gubernaculum, Hanley, V. Bertin, Revision d. Tellinidés, p. 344, No. 31. ' Abbild, u. Beschreib, neuer od. wen. gek. Conchyl., Ill, p. 56. - Gmelin's Tellina papyracea = Tellina {Metis) lacunosa, Ch. Spengler quotes: Lister, Hist. Conch., pl. 395, fig. 242 as a synonym of his T. papyracea; this figure according to Mörch, resembles more closely Spenglers T. sinuata. Ill 207 The sound of Koh Chang, 3—5 fathoms, soft clay (^/s). N. of Koh Kong, 8 fathoms, mud (Va). Long. 14—48 mm. — (Long. 48 mm., alt. 37 mm., crass. 14 mm.) — (Long. 44 mm., alt. 31 mm., crass. 15 mm.). Distribution:— Tranquebar (Spengler and Seidelin, Zool. Mus. Copen- hagen), Manilla (Zool. Mus. Copenhagen). Edg. Smith writes to me: "I think 'Central America,' the locality given by Hanley {T. giibernaculum) is a mistake. We have it from Bombay." I believe here reference is made to the specimens from Bombay determined by Melvill and Abercrombie' as Macoma truncata, Jonas. As M.trun- cata, Jonas, is easily mistaken for the species we are here considering, some of the localities given for truncata should undoubtedly be transferred to T. papyracea, Spengl. As the original specimens of Spengler's papyracea are in the Zoological Museum of the University of Copenhagen it has been possible for me to verify the fact that the specimens from the Gulf of Siam belong to the same species. I sent some of the specimens from the Gulf of Siam to Mr. Edg. Smith, and he kindly informed me that they "agree with giibernaculum of Hanley;" consequently, it is proved that Hanley's species should be regarded as a synonym of Spengler's papyracea, which name has the priority. Mörch " states that T. truncata, Jonas, is identical with T. papyracea, Spengl., but this is certainly wrong; truncata, according to Jonas's diagnosis, presents several peculiarities which are undoubtedly charac- teristic of that species. Tellina (Macoma) fallax, Berlin. Macoma fallax, V. Bertin, Revision d. Tellinidés (Nouv. Arcliives du Museum d'Histoire Naturelle, 2 Ser., I, Paris), 1878, p. 343, No. 29, pi. 8, fig. 4. Sound of Koh Chang, 3—5 fathoms, soft clay (^'Vs). Between Koh Kahdat and Koh Kut, 6 fathoms, clay mixed with sand (^^/a). Long. 5—29 mm. (long. 29 mm., alt. 17 mm., crass. 12 mm.). Distribution unknown. Although the shells from the Gulf of Siam do not reach the size of that figured by Bertin, and although Bertin's brief diagnosis is not of much use as a guide, I think I can safely refer my individuals to the present species, which has undoubtedly often been confused with T. Candida, Lam. Tellina (Macoma) lilium, Hani. (PI. IV, Figs. 1-2) Tellina Lilium, Hanley, Proc. Zool. Soc. London, 1844, p. 147. — lilium, — Hanley in Sowerby, Thesaur. Conchy]., 1, p. 303, No. 158, pi. 58, fig. 85. — — — Reeve, Conchol. icon., XVII, Tellina, Sp. 174. ' Mem. and Proc. of the Manchester Liter, and Phil. Soc, 4 Ser., vol. VII, p. 50. 2 Malakozoolog. Blatter, XVU, 1870, p. 116. 208 112 Tellina Lilium, Hanley, Römer in Martini u. Chemnitz, Conchyl. Cabin., XBd., 4 Abtli , p. 253, No. 157, pi. 48, figs. 4—6. Macoma liïinm, Hanley, V. Bertin, Revision d. Tellinidés, p. 337, No. 12. — Lilium, — HiDALdo, Fauna malacol. de 1. Isl. Filipinas, U, 1903, p. 160, No. 279. Tellina donaciformis, Deshayes, Proc. Zool. Soc. London, 1854, p. 3.'i7, No. 182. — donacinifonnis, — Reeve, Concliol. icon., XVII, Tellina, Sp. 299. — I Huniala) donaciformis, Deshayes, V. Bertin, Revision d. Tellinidés, p. 290, No. 178. (Donax) Tellina Essingtonensis, Deshayes, Reeve, Conchol. icon., XVII, 1866, Tellina, Sp. 73. Macoma Essingtonensis, Deshayes, V. Bertin, Revision d. Tellinidés, p. 342, No. 26. E. of Koh Mak, 20 fathoms, mud ('/s). Between Koh Kut and Koh Kahdat, 6 — 10 fathoms, clay and shells (2 + '''/a). W. of Koh Kut, 30 fathoms, sand and mud ("/s). Long. 10 — 18 mm. Distribution:— Singapore (2 — 3 fathoms, Danish Exp. to Siam). — Philip- pines, Torres Strait, Port Essington, Lane Cove (Port Jackson), Isl. Ravvak (Freycinet). Tellina (Macoma) Moluccensis, Mart. Tellina Moluccensis, E. v. Martens, Annals and Magaz. of Nat. Hist., 3 Ser., vol. 16, 1865, p. 430, No. 5. — (Metis) Moluccensis, E. v. Martens, Römer in Martini u. Chemnitz, Conchyl. Cabin., XBd., 4 Abth. p. 213, No. 129, pi. 41, figs. 4-6. Metis Moluccensis, E. v. Martens, V. Bertin, Révision d. Tellinidés, p. 332, No. 13. Surface mud along the coast of Lem Ngob, low tide ('/a). Coast of Lem Ngob, low tide, stones (^/a). Long. 17 mm., alt. 13 mm. Distribution: — Moluccas. I have referred the present species to the subgenus Macoma; it is difficult to understand why previous authors have referred it to the subgenus Metis. Tellina (Macoma) tenuisculpta n. sp. (PI. IV, Figs. 3—5). The valves of this species are triangular in form, white and rather thin, and compressed; they are somewhat gaping at the ends, epecially the posterior end. The umbones are situated at about the middle of the axis of the shell, the upper margin slopes abruptly down on both sides, the posterior end is prolonged some- what in an acute, rostrum-like manner, and the ventral side is gently curved. The different individuals exhibit a more or less distinct "Tellina-curvature." The sur- face is covered with narrow, close-set, finely crenulated, concentric, raised lines which are irregular and at different mutual distances. The interstices between the concen- tric striæ are closely set with fine, irregular radial folds and striæ which are not all equally fine; this sculpture gives a rough appearance to the surface. The interior of the valves is white and somewhat glossy. The right valve has two cardinal teeth of which the hinder is the larger and is bifid; the left valve has also two cardinal teeth, the anterior is stout and bifid while the posterior is slender. The 113 209 pallia! sinus ascends from the posterior muscle-impression upwards in a curve and then descends obliquely down towards the palliai line, which it meets somewhat before the palliai line has reached the anterior muscle-impression. Long. 9 mm., alt. 65 mm., crass. 3-5 mm. North end of Koh Chang, 1 fathom, coral blocks (2 -f '"/a). North end of Koh Chang, 12 fathoms, old coral blocks (1 -|- *"/-'). West coast of Koh Chang, 1 fathom, old coral blocks (^/s). South-west end of Koh Chang, 1 fathom, corals (^/a). Koh Kahdat, 1 fathom, sand ('/s). Koh Kahdat, 1—2 fathoms, corals ('/s). This species is most closely allied to the group:— M. inqiiinata, Desh., nasiita, Conr., constricta, Brug., etc. It is, however, easily distinguished from them by its characteristic sculpture. It varies considerably in form, which is no doubt due to its inhabiting old coral blocks. In the material collected are several individuals which are more ovate-oblong in form than the above description indicates; but this is more particularly the case with the younger individuals, almost all of which are more oblong than are the (apparently) full-grown ones. Fam. Psammobiidae. Asaphis deflorata L. Venus deflorata, Linnk, Systema Naturae, ed. X, 1758, p. G87, No. 108. — ed. XII, p. 1133, No. 132. — ed. XIII cur. Gmelin, p. 3274, No. 24. — — — DiLLWYN, Descript. catalogue of reo. shells, I, 1817, p. 186, No. 65. — — — Römer, Krit. Untersuch, d. Arten d. MoUuskengeschl. Venus, 1857, p. 52, No. 24. Asaphis — — Mörch, Journ. de Conchyl., VII, 1858, p. 139, No. 3. — Catal. Yoldi, II, 1853, p. 9, No. 83. Capsa — — Reeve, Conchol. icon., X, 1856, Capsa, Sp. 1. Asaphis — — V. Bertin, Revision d. Garidees, 1880, p. 80, No. 5. — — — Hidalgo, Fauna malacol. de I. isl. P'ihpinas, 1903, II, p. 73, No. 149. Capsa eflorata, d'Orbigny, Moll, de I'ile de Cuba, II, 1853, p. 258, No. 457. Venus violascens, Forskål, Descript. animal, quæ in itinere orientali observ., 1775, p. XXXI, No. 28. Asaphis — — Mörch, Journ. de Conchyl., VII, 1858, p. 138, No. 2. — — — V. Bertin, Revision d. Garidees, 1880, p. 80, No. 2. Tellina anomala, Born, Inde.x rer. natur. Mus. Cæs. Vindobon., 1, Testacea, 1778, p. 20. — Testacea Mus. Cæs. Vindobon., 1780, p. 31. — — — Chemnitz, Conchyl. Cabin., VI, 1782, p. 93, pi. 9, figs. 79—82. Cardiam coccinea, Martyn, The Universal Conchologist, 1784, No. 135. Asaphis — — Mörch, Journ. de Conchyl., VII, 1858, p. 140, No. 4. — — — V. Bertin, Revision d. Garidees, 1880, p. 79, No. 1. — — — Dall and Simpson, The Mollusca of Porto Rico, 1901, p. 47(i. Venus versicolor, Gmelin, Systema Naturae, 1790, p. 3281, No. 63. — purpurata, — loc. cit., p. 3289, No. 100, (Monstr.?). Capsa rugosa, Lamarc k, Système d. anim. s. vert., 1802. p. 125. Sanguinolaria rugosa, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 511, No. 4. — éd. 2, VI, 1835, p. 170, No. 4. Capsula — — Schumacher, Essai dun nouv. .syst. d. habit, d. vers, test., 1817, pp. 130—31, pi. 9, fig. 1. Psanimobia — — Sowerby, Genera of shells, No. 35, pi. 55, fig. 1. 1). K. 1). VIdensli. Selsk. Skr., 7. Rielike. natuividensk. o(,' niiilhcm. Afd. V. 3. 27 210 114 Psammocola rtigosa, Lamahck, Blainville, Manuel de Malacologie, 1825, p. 564. Asaphis — — Morlf.t, Journ. de Conehyl., vol. 37, 1889, p. 172, No. 84. — — — P. FhSCHF.ii, Moll. de l'Indo-Chine, p. 241. _• — — E. V. Martens, Süss- u. Brackwasser-Moll. d. Indischen Archipels, 1897, p. 252. Sangainohiria dicliotoma, Anton, Verzeichn. d. Conehyl. in d. Samml. v. H.E.Anton, 1839, p. 4, No. 123. Asaphis — — Mörch, Journ. de Conehyl., VII, 1858, p. 138, No. 1. Sanguinolaria — — V. Bertin, Revision d. Garidées, 1880, p. 80, No. 4 i Asaphis arenosa, Rumph.). Asaphis — — Hidalgo, Fauna malacol. de 1. isl. Filipinas, 1903, II, p. 74, No. 150. — — — Dautzenberg et Fischer, .lourn. de Concliyl., vol. 53, 1905, p. 233. Koh Chang ('/a). Coasts of Koh Chang C/s). Koh Lorn (13). Koh Mak, sandy coast (3/2). Strand of Koh Kahdat (»/a). Islands in the Gulf of Siam (Morlet). Long. 8 — 74 mm. Distribution: — Singapore, Salang, Mergui Isis., Andamans, Nicobars, Tranquebar, Ceylon, Maldive Isis., Karachi, Bombay, Persian Gulf, Aden, Red Sea, Suez, Zanzibar, Amirantes, Seychelles, Madagascar, Mascarenes. — Poulo Condor, Tonkin, Hong Kong, Japan, Loo Choo Isis., Philippines, Sumatra, Java, Moluccas, Flores, Timor, Aru Isis, (and several localities in the Malay Archip.), New Guinea, Salomon Isis., Torres Strait, North and East Australia, New Caledonia, New Zealand, Mariannes, South Sea Isis. — Bermuda Isis., Florida, Vera Cruz, Mexico to Brazil, Greater and Lesser Antilles. I have at my disposal a great number of specimens of Asaphis deflorafa from different West Indian localities, but it has not been possible for me to find con- stant characters which would distinguish them from individuals from East Indian habitats. Psammobia scabra, Chemn. Tellina scabra, Chemnitz, Conehyl. Cabin., VI, 1782, p. 102, pi. 10, fig. 94. Psammobia scabru, Chemnitz, E. v. Martens, Süss- u. Brackwasser-Mollusken d. Ind. Archipels, 1897, p. 248, No. 12. — maculosa, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 513, No. 5. — éd. 2, VI, 1835, p. 174. No. 5. Gari — — V. Bertin, Révision d. Garidées, p. 105, No. 5. Psammobia ornata, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 323, No. 27. — — — Reeve, Conchol. icon., X, Psammobia, Sp. 26. V. Bertin, Revision d. Garidées, p. 105, No. 8. Hidalgo, Fauna malacol. de 1. isl. Filipinas, II, p. 77, No. 154. Proc. Zool. Soc. London, XXII, 1854, p. 324, No. 30. Reeve, Conchol. icon., X, Psammobia, Sp. 34. V. Bertin, Révision d. Garidées, p. 105, No. 6. Hidalgo, Fauna malacol. d. 1. isl. Filipinas, II, p. 76, No. 152. Proc. Zool. Soc. London, XXII, 18.54, p. 324, No. 31. Reeve, Conchol. icon., X, Psammobia, Sp. 9. V. Bertin, Révision d. Garidées, p. 105, No. 7. Dunker, Inde.\ molluscor. mar. Japon., 1882, p. 187. Hidalgo, Fauua malacol. de 1. isl. Filipinas, II, p. 76, No. 153. Gari — Psammobici rubicunda, Gari Psammobia — — corriigata. Gari Psammobia — 115 211 Psammobia marmorea, Df.shayfs, Proc. Zool. Soc. London, XXII, 1854, p. 324, No. 32. — — — Reeve, Concliol. icon., X, Psammobia, Sp. 27. Gari — — V. Bertin, Revision d Garidées, p. 106, No. 10. South of Koh Chuen, 30 fathoms, shells (fragment). Between Koh Mesan and Koli Chuen, 25 — 38 fathoms, stones with shells ('/a). Long. 42 mm. Distribution: — Andamans, Ceylon, Persian Gulf, Muscat (Arabia), Gulf of Aden, Comoro, Madagascar, Zanzibar, Durban (S. Africa). — Philippines, Japan, Moluccas, Torres Strait, east and south coasts of Australia, New Caledonia, Darnley Isl., Viti Isis., Tahiti. Psammobia zonalis, Lam. Psammotœa zonalis, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 517. No. 2. — cd. 2, VI, 1835, p. 182, No. 2. Psammotea — — Delessert, Recueil de coquilles décr. p. Lamarck, 1841, pi. ,'), lig. 9. Psammobia — — Reeve, Conehol. icon., X, Psammobia, Sp. 29. Gari — — V. Bertin, Révision d. Garidées, p. 109, No. 27. Psammobia — — Edg. Smith, Lamellibrancliiata of the Cliallenger Exped., pp. 94, (and 93). Gari — — Pritchard and Gati.iif, Proc. Roy. Soc. Victoria, vol. 10, 1903, p. 113. Psammobia radiata. Dunker in Philippi, Abbild, u. Besclireib. neuer od. wen. gek. Concliyl., I, 1845, p. 194, No. 3, pi. 2, fig. 5. — — — Dunker, Index molluseor. mar. Japon., 1882, p. 187. — — — V. Martens, Süss- u. Brackwasser-MoII. d. Ind. Archipels, 1897, p. 244, No. 7. — pnella, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 320, No. 14. — — — Reeve, Conchol. icon., X, Psammobia, Sp. 2. Gari — — V. B?:rtin, Revision d. Garidées, p. Ill, No. 35. Psammobia striata, — Proc. Zool. Soc. London, XXII, 1854, p. 321, No. 20. — compta, — loc. cit., p. 321, No. 18. — — — Reeve, Conchol. icon., X, Psammobia, Sp. 24. — — — HiDAi.GO, Estud. prelim, sobre la fauna malacol. de las isl. Filipinas, II, 1903, p. 83, No. 165. Gari — — V. Bertin, Revision d. Garidées, p. 110, No. 34. Psammobia amcthystiis, Reeve (non Wood), Reeve. Conchol. icon., X, Psammobia, Sp. 19. — Tellinœformis, Deshayes in Reeve, loc. cit., Sp. 31. — — — V. Bertin, Révision d. Garidées, p. 109, No. 26. Between Koh Mesan and Cape Liant, 5 — 9 fathoms (2). North of Koh Kahdat, 4—5 fathoms, coarse sand (^'a). Koh Kahdat, 1 fathom, sand (1). Long. 20—41 mm. Distribution:— Ceylon. — Japan, Loo Choo Isis., Philippines, Moluccas, Java, east and south coasts of Australia, Tasmania, New Caledonia. The specimens from tlie Gulf of Siam exactly agree with P. compta, Desh. I rely upon Edg. Smith's authority (loc. cit.) in referring this species to P. zonalis. Lam. Psammobia tenuis, Desh. Psammobia leniiis, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 320, No. 16. — — — Reeve, Conchol. icon., X, Psammobia, Sp. 37 b (non 37 a = P. anomala, Desh. var.j. 27* 212 116 Gari tenuis, Düshayes, V. Bertin, Revision d. Garidées, p. 110, No. aO. Psammohia tenuis, Deshaves, Hidalgo, Estud. prelim, sobre la fauna malacol. de las isl. Filipinas, II, p. 82, No. 164. N. of Koh Kahdat, 4 — 5 fathoms, coarse sand (1). Koh Kahdat, 1 fathom, sand (3). W. of Koh Kut, 30 fathoms, sand and mud (-'/a). Long. 5 — 25 mm. Distribution:— Philippines. The specimens from the Gulf of Siam are pink in colour. Psammobia anomala, Desh. Psammobia anomala, Deshayes, Pioc. Zool. See. London, XXII, 18r)4, p. 320, No. 15. — — — Reeve, Conchol. icon., X, Psammobia, Sp. .5. — — — Edg. Smith, Lamellibranchiata of the Challenger Expedition, p. 95. Gari — — V. Bertin, Révision d. Garidées, p. 110, No. 33. Psammobia — — Hidalgo, Estud. prelim, sobre la fauna nialacol. de las isl. Filipinas, II, p. 87, No. 170. Gulf of Rayong, 7 — 10 fathoms, sand, mud (I'/a). Koh Chuen, 30 fathoms (1). Between Koh Kut and Koh Kahdat, 10 fathoms, shells ('/s). Long. 19—23 mm. Distribution: — Madras. — Philippines, Japan, Borneo, Torres Strait, north and east coasts of Australia. Psammobia simplex, Sow. (PI. IV, Figs. G-8). Psammobia simplex, G. B. Sowkrby, Proceed. Malacolog. Soc. London, I, 1894 (1895), p. 159, pi. 12, lig. 21. Gulf of Rayong, 7—10 fathoms, sand and mud (1 + ^li). Around Koh Kahdat, 8—10 fathoms, mud {V2). Between Koh Kut and Koh Kahdat, 10 fathoms, shells ("/2). South and west of Koh Kut, 15—20 fathoms, mud (1 -|- V2). N. of Koh Kut, 10 fathoms, mud (*/2). Long. 5 — 14 mm. (long. 14 mm., alt. 8 mm.). Distribution:— Singapore (Sv. Gad, shallow water; -'/a valves). Karachi (Melvill & Standen), Hong Kong (Sowerby). SowERBY gives "Longit. 9, alt. 5 mm." as the measurements of his specimens; those from the Gulf of Siam are of larger dimensions; they are of a pure white colour. Elizia orbiculata, Wood. Solen orbiculatus. Wood, Index Testaceologicus, 1828, Supplem. p. 3, No. 4, pi. 1, fig. 4. Psammobia orbicularis, Deshayes, Magazin de Zoologie p. Guérin-Méneville. Mollusques, 1839, pl. 7. Solctellina orbiculata, Wood, Reeve, Conchol. icon., X, Soletellina, Sp. 18. Elizia — — Adams, Genera of recent Mollusca, II, p. 393, pl. 103, fig. 5. — orbicularis, — Bertin, Revision d. Garidées, p. 129, No. 2. — orbiculata, — J. de Morgan, Bull, de la Soc. Zool, de France, X, 1885, p. 36(j, No. 2(). — — — E. V. Martens, Süss- u. Brackwasser-MoII. d. Ind. Archip., p. 233. Soletellina reversa, Beeve, Conchol. icon., X, Soletellina, Sp. 17. 117 213 Siam (J. de Morgan). The Danish Expedition to Slam collected no specimens of this species. Distribution: — Malacca, Singapore, Poulo-Penang. — Borneo, Sumatra. Soletellina Chinensis, Chemn. Solen Diphos Chinensis, Chemnitz, Conchyl. Cabin., XI, 17'J5, p. 200, pi. 198, fig. 19.33. SolcnotkUina chinensis, — Mörch, Catal. conchyl. quæ rel. com. de Yoldi, II, 1853, p. 9, No. 88. — Chinensis, — Dunker, Index moll. mar. Japon., 1882, p. 187. Soletellina chinensis, — E. v. Martens, Süss- u. Braekwasser-Moll. d. Ind. Archip., p. '233. — truncata. Reeve, Conchol. icon.. X, Soletellina, Sp. 9. — — Gmel.?, E. v. Marten.s, Proc. Zool. Soc. London, 1860, p. 18. — planulata, Reeve, Conchol. icon., X, Soletellina, Sp. 15. Hialula — — Bertin, Revision d. Garidces, p. 87, No. 8. Siam (Ed. v. Marte.ns). The Danish Expedition to Siam collected no specimens of this species. Distribution: — China, Japan, Moluccas. Psammotaea violacea, Lam. Psammotœa violacea, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 517, No. 1. — cd. '2, VI, p. 181, No. 1. — — — Hanley, Catal. of rec. biv. shells, p. (iO, Suppl. pi. 12, fig. 60. Capsella — Reeve, Conchol. icon., X, Capsella, Sp. 6. — — — E.V.Martens, Proc. Zool. Soc. London, 1860, p. 18. Hiatula tPsammotœa) violacea, Lamarck, V. Bertin, Révision d. Garidées, p. 96, No. 34. Psammotaea violacea, Hanley, E. v. Martens, Süss- u. lirackwasser-MoU. d. Ind. Archip., p. 239, No. 2. Psammotœa — Lamarck, Hidalgo, Fauna malacol. de 1. isl. Filipinas. Il, p. 95, No. 186. Soletellina, — — Melvill & Standen, Proc. Zool. Soc. London, 1900, p. . — aciitocarinatus, Sowerby, P. Fischer, Catal. d. Moll, de I'lndo-Chine, p. 240. "Siani" (Sowerby). The Danish Expedition to Siam collected no specimens of this species. Donax (Serrula) incarnatus, Chemn. (PI. IV, Figs. 12—13). Donax incarnata, Chemnitz, Conchyl. Cabin., VI, 1782, p. 265, pi. 26, fig. 259. — — — Reeve, Conchol. icon., VIII, Donax, Sp. 53. incarnatus, — Sowerby, Thesaur. Conchyl., Ill, p. 311, No. 43, pi. 283, figs. 98— 99. — {Serrula) incarnatus, Chemnitz, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 3 Abth., p. 76, No. 47, pi. 2, fig. 11 ; pi. 13, figs. 9 — 12. — — — — V. Bertin, Revision d. Donacidées, p. 90, No. 26. — incarnatus, Chemnitz, Dautzenberg & Fischer, Journ. de Conchyl., vol. 53, 1905, p. 468. — vol. 54, 1906, p. 219. — Dysoni, Deshaye.s, Proc. Zool. Soc. London, XXII, 1854, p. 353, No. 167. — — — Reeve, Conchol. icon., VIII, Donax, Sp. 54. — (Serrula) Dijsoni, Deshayes, Römer in Martini & Chemnitz, Conchyl. Cabin., X Bd., 3 Abth., p. 69, No. 42, pi. 12, figs. 8— 10. — — — — V. Bertin, Revision d. Donacidées, p. 90, No. 27. (non D. Dysoni, Lischke = D. semigranosus, Dkr.). "Siam" (Sowerby). The Danish Expedition to Siam collected no specimens of this species. Distribution: — Malacca, Tranquebar, Malabar Coast, Bombay. — • Annam, Cochin China. It is doubtful whether the authors (e. g. Römer) have really had Chemnitz's species incarnatus for examination, Römer writes that Reeve does not indicate the same species by the name incarnatus, as that to which he himself has applied that name, and he is undoubtedly right in this. Spengler's specimens of D. in- carnatus from Tranquebar (determined by him as D. muricata L.) are in the Zoo- logical Museum of the University of Copenhagen; they precisely agree with CHEMNrrz's figure of incarnatus. 216 120 I quite agree with J. C. Melvill and Abercrombie when they write' that: "D. Dysoni appears to be incarnatus in a young form." Donax (Serrula) nitidus, Desh. Donax nitida, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 350, No. 153. — — — Reeve, Conchol. icon., VIII, Donax, Sp. 34. — (Serrula) nitidus, Deshayes, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 3 Abth., p. 51 (non D. nitidus, Sowerby, Thesaur. Conchyl., fide Edg. Smith). — — — — V. Beutin, Revision d. Donacidées, p. 88, No. 21. — nitidus, Deshaye.s, Edg. Smith, Lamellibranchiata of the Challenger Expedition, p. 112. Between Koh Rin and Cliff Rocli, 15 fathoms ('/2). N. of Koh Kam, 5 fathoms, gravel (^/s). Between Koh Mesan and Cape Liant, 5 — 9 fathoms, sand (V2). W. of Koh Kut, 15 fathoms ('/a). Long. 3 — 10 mm. Distribution: — Karachi and Mekran Coast (Melvh.l & Standen). — Cape York, Moreton Bay, Port Jackson (Sydney). Donax (Latona) cuneatus L. Donax cuneata, Linné, Systema Naturae, ed. X, 1758, p. ü83. No. 87 (p.p.). — ed. XII, p. 1127, No. 108. — Mus. Lud. Ulricæ reg., p. 495, No. 52. — — — Chemnitz, Conchyl. Cabin., VI, 1782, p. 266, pi. 26, fig. 260. — — — Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 546, No. 3. — éd. 2, VI, p. 240, No. 3. — — — Reeve, Conchol. icon., VIII, Donax, Sp. 15. — (Latona) cuneatus, Linné, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 3 Abth., p. 82, No. 51, pi. 2, fig. 10; pi. 14, figs. 9-10. — cuneatus, Linné, Sowerby, Thesaur. Conchyl., Ill, p. 311, No. 39, pi. 282, figs. 88—90. — — — V. Beutin, Révision d. Donacidées, 1881, p. 114, No. 105. — — — HiDAi.oo, Fauna malacol. de 1. isl. Filipinas, II, p. 173, No. 296. — bicoloT, Gmblin, Syst. Nat., ed. XIII, 1790, p. 3265, No. 16. — — — Lamarck, Hist. nat. d. anim. s. vert., V, p. 548, No. 13. — éd. 2, VI, p. 243, No. 13. — — Lamarck, Reeve, Conchol. icon., VIII, Donax, Sp. 28. — — — Sowerby, Thesaur. Conchyl, III, p. 311, No. 42, pi. 283, figs. 102 — 3 (non D.WcoJor, Römer). — granosa, — Hist. nat. d. anim. s. vert., V, 1818, p. 547, No. 8. — éd. 2, VI, p. 242, No. 8. — granosus, — V. Bertin, Révision d. Donacidées, p. 114 (non D.granosus, Römer). — australis, — Hist. nat. d. anim. s. vert., V, 1818, p. 548, No. 11. — éd. 2, VI, p. 242, No. 11. — — — QuoY et Gaimard, Voyage de l'Astrolabe, JI, 1833, p. 493, pi. 81, figs. 20—22. — obscura, Deshayes, Encyclop. method., II, 1830, p. 98, No. 13. Koh Kahdat, 1 fathom, sand (17). Koh Mak, sandy coast (4 -j- ^/s). Long. 15 — 28 mm. Distribution: — Andamans, Coromandel Coast, Ceylon, Seychelles and Amirautés, Madagascar, Mascarenes, Zanzibar. — Poulo Condor, Philippines, Japan, Amboina, Timor, New Guinea, Bismarck Archip., New Caledonia, Lifu, Viti Isis., Samoa Isis. ' The marine Mollusca of Bombay (Mem. and Proceed. Manchester Lit. and Phil. Soc, 4 Ser., vol. VII), p. 47. 121 217 The specimens from the Gulf of Siam exhibit, as is always the case in this species, great variation in their coloration ; there are specimens which are'almost entirely white, and individuals in which the rays are slightly indicated, also forms in which the rays are very definite, and dark brown, lilac, etc. in colour. Römek's D. Deshayesii (Dkr.) is scarcely Dunker's species; it is more probably a form of D. ciineatus, and this V. Bertin and Hidalgo also think. Zelebor's Donax (Latona) granosus^ from Amboina does not belong to the present species; as far as I can see it is nearer to 0. englyptus, Dkr. (= D. compressas, Lam.), at any rate it is not Lamarck's granosus. Donax (Latona) faba, Ch. Donax Faba, Chemnitz, Conchyl. Cabin., VI, 1782, p. 270, pi. 20. figs. 266 — 67. — — — SowERBY, Thesaur. Conchyl., Ill, 1866, p. 312, No. 45, pi. 283, figs. 108 9. — {Latona) Faba, Chemnitz, Römer in Martini u. Chemnitz, Conchyl. Cabin., X Hd., 3 Abth., 1869, p. 88, pi. 2, figs. 12— 13 and 15-17. — — — — V. Bertin, Revision d. Donacidees, p. 109, No. 94. — faba, Chemnitz, P.Fischer, Catalogue d. Moll, de llndo Chine, p. 241. — Faba, — Hidalgo, Fauna malacol. de I. isl. Filipinas, 11, p. 169, No. 293. — radiata, Spengler, Schröter, Einleit. in d. Conchylienkenntn., Ill, 1786, p. 104, No. 11, pi. 8, fig. 3. — — Schröter, Gmelin, Syst. Nat. ed. Xlll, 1790, p. 3266, No. 17. — radians, Lamarck, Hist. nat. d. aniin. s. vert., V, 1818, p. 547, No. 6. — éd. 2, VI, p. 241, No. 6. — — — Encydop. method. Moll., pl. 261, fig. 7 (non radians, Reeve et Sowcrby). Coast of Lem Ngob (1). South coast of Koh Chang, sand (5). Koh Kahdat, 1 fathom, sand (43). Koh Mak, sandy coast (1 + '^/-)- Islands in the Gulf of Siam (L. Morlet). Long. 14 — 26 mm. Distribution:— Salanga, Madras, Gulf of Manaar, Malabar Coast, Gulf of Oman, Assab (Caramagna), Mauritius, "South Africa" (Sowerby). — Cochin'China, Tonkin (banks of Song-kai (Red River)), Hong Kong, Liukiu Isis. (Höttger), Philip- pines, Moluccas, Java, New Guinea, Sorong, Port Jackson, New Caledonia, Viti Isis. Sowerby- considers D. Deshayesii, Dunker (from Lower Guinea), to be a variety of D. faba, Chemn. — D. splendens, Dkr., ^ is very closely related to the present species. Fam. Cardiliidae. Cardilia inermis, Desh. Cardilia inermis, Deshavf„s, Magazin de Zoologie. 1844, p. 6, pl. 100. — — — P. Fischer, Journ. de Conchyl., 1861, vol. IX, p. 342. — — — Reeve, Conchol. icon., vol. XIX, Cardilia, Sp. 2. ' Dunker u. Zelebor, Verhandl. d. k. k. zool. botan. Ges. Wien, 1866. p. 916. — G. v. Fhaienpeld, Mollusken d. Novara E.\pedition, p. 15, pl. 2, fig. 27. - Thesaurus Conchyliorum, 111, Donax, pi. IV, figs. 108-9 (and the explanation of plates). ' Novitates Conchologicac. Meeres Conchyl., p. 79, No. 87, pl. 25, fig. 5. I). K. I). Vlilensk. .Selsk. Skr.. 7. Ha-kkc, n.ilurvidcnsk. of! ni;illi AW V. 3. 28 218 122 West of Koh Kut, 30 fathoms, sand and mud (Va). Long. 6 mm., alt. 8 mm. Distribution:— Philippines (Cuming), Sumatra (Mahtin, Deshayes). Fam. Mesodesmatidae. Mesodesma (Atactodea') glabrata, Lam. Crassatella glabrata, Lamarck, Annales du Mus. d'Hist. Nat., VI, 1805, p. 408 (nomen). — - — Hist. nat. d. anim. s. vert., V, 1818, p. 482, No. 5. — éd. 2, VI, p. Ill, No. 5. Mesodesma — Deshayes, Hist. nat. d. anira. s. vert., éd. 2, VI, p. 133, No. 2. — — Lamarck, Savigny, Descrlpt. de l'Egypte. Mollusques, pi. 8, fig. 5. Papliia — Gmei.in, H. & A. Adams, Genera of recent Mollusca, 111, 1858, pi. 106, fig. 1. Mesodesma — Deshayes, Reeve, Conchol. icon., VIll, Mesodesma, Sp. 20. — — Lamarck, Issel, Malacol. d. Mar Rosso, 1869, p. 53, No. 18. — — — Pagenstecher, Ueber d. v. Kossmann am Rothen Meere ges. Mollusken, 1877, p. 41, No. 32. — glabratum, — E. v. Martens, Moll. d. Maskarenen u. Seychellen, 1880, p. 152. — (Paphia) glabratum, Lamarck, E.v. Martens, Journ. Linnean Soc, Zoology, vol. 21, 1887, p. 215, No. 375. — glabratum, Lamarck, Dautzenherg & Fischer, Journ. de Conchyl., vol. 53, 1905, p. 233. Mactra sulcata, Valenciennes, Encyclop. method., 1791, pi. 257, fig. 3 (nomen). Mesodesma mitis, Deshayes, Reeve, Conchol. icon., VIII, Mesodesma, Sp. 29. — Savigngi, Jousseaume, Descr. d Moll. rec. p. Faurot dans la mer Rouge et le golfe d'Aden, (1888), p. 206, No. 142. South coast of Koh Chang, shallow water, buried in the sand (79). Koh Kahdat, ] fathom, sand (8). Koh Mak, sandy coast ('/a). Long. 10 — 31 mm. Distribution: — Singapore, Salang, Mergui Isis., Andamans, Ceylon ("Extends from Ceylon throughout the Indian Ocean," Melvill and Sykes), Maldives, Gulf of Aden, Red Sea, Suez, Seychelles, Amirautés, Madagascar, Mascarenes, Mozambique, Querimba Isis. — Philippines (v. Martens), Tonkin, Thursday Isl. (Torres Strait), "Australia" (v. Martens). Mesodesma striata, Chemn., and M. glabrata, Lam., have undoubtedly frequently been confused with each other by several authors; thus, M. striata is recorded by Caramagna"^ and Mörch, ' to have been taken from the Red Sea and at Aden ;f and I believe that also Morlet's^ M. striata, from "lies du golfe de Siani" unquestionably refers to specimens of M. glabrata, Lam. In addition to this, these two species are very badly characterized and figured. Chemnitz says, e. g. regarding his striata, that "nur allein die Wirbelspitzen sind fast völlig glatt," but this is seen very • P. Fischer (Manuel de Conchyl., p. 113) rejects Lamarck's generic name Paphia and adopts Swainson's name Eryx. Dall (Proc. Malacol. Soc. London, 1, p. 213| thinks that tliis name is not satis- factory as it is "preoccupied in zoology" and makes a new name, viz. Atactodea. - Proc. Zool. Soc. London, 1891, p. 435. 3 Catal. conchyl. quæ rel. Yoldi, II, p. 16, No, 166. " Journal de Conchyliologie, vol. 37, 1889, p. 172, No. 87. 123 219 indistinctly in his figure; and Lamarck observes regarding glabrala: "nalibiis um- bonibusque glabratis," but this slight ditïerence which is probably intended to be the chief distinguishing point (the striation of the rest of the shell being no doubt almost similar in both the species), is confined to a matter of taste. On examining the figures, e. g. of glabrata by Adams (loc. cit.) and of striata by Reeve (sp. 10), it will be seen that the sculpture is almost similar, and that the form differs but slightly; but the material oi M. glabrata at my disposal shows that the outline varies highly — from a high triangle (long. 27 mm., alt. 23 mm.) to an oblong- ovate form (long. 24 mm., alt. 18 mm.). — It is desirable that these two forms should be compared with each other, and especially that striata should be more accurately characterized. In glabrata the regularly-arranged concentric striation begins gene- rally when the shell has reached a height of about 8 — 12 mm., but it may often be traced before this. Davila crassula, Desh. Mesodesma crassula, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 336, No. 87. — — — Reeve, Conchol. icon., V!II, Mesodesma, Sp. 26. Davila — — H. & A. Adam.s, Genera of rec. Mollusca, pi. 106, fig. 6. Mesodesma — — Hidalgo, Fauna malacol. de 1. isl. Filipinas, II, p. 66, fig. 13.5. Koli Kahdat, 1—5 fathoms, sand (3). On the coast of Koh Kahdat (^h). Long. 8 — 18 mm. Distribution: — Elphinstone Isl. (Mergui Archip., v. Martens), Philippines. Ervilia bisculpta, Gould. (PI. I\', Figs. 14-16). EruilUt biscnlpla, Goui.d, Proceed. Boston Soc. Nat. Hist., VIII, 1861 — 62, p. 28. - Olia Conchol., p. 166. — — — Edg. Smith, Report on the Laniellibranchiata of the Challenger Exped., p. 80. Ervillia — — Pilsbry, Catal. Mar. Moll. Japan, 1895, p. 118. Ervilia — — Hedley, Proc. Linn. Soc. New South Wales, vol. 31, 1906, p. 47'J, pi. 36, fig. 8. — australis, Angas, Proc. Zool. Soc. London, 1877, p. 175, pi. 26, flg. 21. — incolor, Deshayes, MSS. in Brit. Mus. Corbiila isomeros, Hinds, MSS. in Cuming's Collection, Brit. Mus. Koh Kram, 30 fathoms (/a). N. of Koh Kam, 5 fathoms, gravel (1). Koh Mesan, 15 fathoms, stones (3). Between Koh Mesan and Cape Liant, 5—9 fathoms, sand (42). W. of Koh Chuen, 5 fathoms, gravel (1). North end of Koh Chang, 1 — 2 fathoms, old coral blocks ('/s). Koh Kahdat (6). Between Koh Kut and Koh Kahdat, 10 fathoms, shells ('/a). W. of Koh Kut, 15 fathoms, mud (4). Long. IS — 5 mm. Distribution: — Singapore (shallow water, Sv. Gad). Durban (Burnup). — Philippines, Japan, Mast Head Reef (Queensland), Port Jackson (Sydney), Sand- wich Isis. Angas's figure of E. australis (Proc. Zool. Soc. London, 1877) corresponds badly with his diagnosis of the same species, and it is upon Edg. Smith's authority alone that I give it as a synonym of E. bisculpta. 28* 220 124 Farn. Mactridae. Mactra (Trigonella) achatina, Ch. Mactra achatina, Chemnitz, Coiichyl. Cabin., XI, 1795, p. 218, pi. 20U, figs. 1957 -58. — — — Reeve, Conchol. icon., VIII, Mactra, Sp. 51. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 2 Abtli., p. 50, No. 49, pi. 17, figs. 3— 4. — — — Edg. Smith, Lamellibranchiata of the Challenger Exped., p. 59. — — — Crosse et Fischer, Journ. de Concliyl., vol. 40, 1892, p. 76, No. 24. maculosa, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 474, No. 8. — éd. 2, VI, p. lOU, No. 8. — ornata. Gray, The Magaz. of Nat. Hist., I, 1837, p. 371. — — — Reeve, Conchol. icon., VIII, Mactra, Sp. 58. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 2 Abth., p. 37, No. 35, pi. 12, figs. 1—3. — adspersa, Dunker, Zeitschr. f. Malakozoologie 1848, p. 180, No. 20. — Philiimm, Abbild, u. Rcschrcib., Ill, p. 135, Mactra, pi. 3, fig. 2. Koh Kalidat (several young individuals). Gulf of Siam, west coast of Cambodge (Pavie). Distribution: — Singapore (shallow water, Sv. Gad), Nicobars, Andamans, Tranquebar, Ceylon, Angrias Bank (Melvill and Standen), Persian Gulf, Aden, Red Sea, Suez, "South Africa" (Sowerby). — Philippines, China, Japan, Torres Strait, Admiralty Isl. Mactra (Trigonella) maculata, Ch. Mactra maculata, Chemnitz, Conchyl. Cabin.. VI, 1782, p. 217, pi. 21, figs. 208-9. — — — Reeve, Conchol. icon., VIII, Mactra, Sp. 56. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI lid., 2 Abth., p. 10, No. 7, pi. 3, figs. 4-5; pi. 16. figs. 5— 6. — — — Hidalgo, Fauna malacol. de I. isl. Filipinas, II, p. 48, No. 100. squalida, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 478, No. 26. — éd. 2,. VI, p. 105, No. 26. — — — Hanlev, Catal. of rec. biv. shells, p. 31, pi. 11, fig. 30. — setosa, QuoY, Voyage de l'Astrolabe, Zoologie, III, 1833, p. 519, pi. 83, figs. 3-4. — Reeoei, Deshayes, Proc. Zool. Soc. London, XXI, 1853, p. 15, No. 3. — — — Reeve, Conchol. icon., VIII, Mactra, Sp. 85. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 2 Abth., p. 66, No. 67, pi 23, fig. 4. — — — MORLET, Journ. de Conchyl., vol.37, 1889, p. 172, No. 88. Islands in the Gulf of Siam (L. Morlet). The Danish Expedition to Siam collected no specimens of this species. Distribution:— Nicobars. — Philippines, Loo Choo Isis. (Yaeyama), Amboina, Sorong, Sulu Isis., Mast Head Reef (Queensland), New Caledonia, Vanikoro Isl., Pelew Isis. Mactra (Trigonella) cuneata, Ch. (PI. IV, Figs. 17—19). Mactra cuneata, Chemnitz, Conchyl. Cabin., VI, 1782, p. 221, pi. 22, fig. 215. — — — Gmelin, Syst. Nat., ed. XIII, 1790, p. 3260, No. 19. — — - Reeve, Conchol. icon., VIII, 1854, Mactra, Sp. 109. 125 221 Mactra ciineata, Chkmnitz, Wkinkaui r in Mahtini u. Chemnitz, Coiicliyl. Cabin., XI lid., 2 Abtli., p. l.'i, No. 10, pi. 4, figs. 3—4. — puriHirea. Spkngleh, SUrivter af Naturhistorie-Selskabet, V Bd., 2 Hefte, 1802, p. 111, No. 17. — corbiculoides. Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 62, No. 4. — — — Reeve, Conchol. icon., VIII, Mactra, Sp. 98. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 2 Abth., p. 91, No. 97, pi. 31, fig. 3. The strand off the Mangrove at the station on Koh Chang, shalhnv water (3). The strand of Koh Kahdat ("'/i). Long. 4—15 mm. Distribution: — Nicobars, Cej'lon, and Gulf of Manaar. The small individuals from the Gulf of Siam agree fairly well with Reeve's cuneata, which is probably founded on not full-grown individuals, at any rate Spengler's original specimens of M. purpurea are considerably larger (long. 31 mm., alt. 27'5 mm., crass. 18 mm.) and are Ihick-valved. I cannot find any difference between tlie latter and Deshayes's corbiculoides, which, judging from the figure and description, agrees in all points with it; therefore, I have not hesitated in giving them as synonyms. Setting aside the outline, the following features are charac- teristic of M. cuneata, Gh.: — the intense dark-lilac colour of the interior of the valves (the lateral teeth are pale), the pale lilac and ash-gray colour of the exterior of the valves, and the beautiful regular striation of the lunule and area. Besides this typical form there are also individuals which are entirely white, without a trace of colour (Chemnitz has already mentioned such specimens), several specimens of this variety were taken at Koh Kahdat. I entirely agree with Weinkauff when he writes (loc. cit. p. 29) that M. lurida, Phil., is very near to M. corbiculoides, Desh.; I think that lurida can scarcely be separated from M. cuneata. Ch. (= corbiculoides, Desh.), as a good species. Mactra (Trigonella) Luzonica, Desh. Maclra Luzonica, Deshayes, Proc. Zool. Soc. London, 1854, p. 64, No. 12. — — — Reeve, Conchol. icon., VIII, Mactra, Sp. 81. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 2 Abth., 1884, p. 49, No. 48, pi. 17, figs. 1-2. — — — Hidalgo, Fauna malacol. de I. isl. Filipinas, II, 1903, p. 50, No. 102. Koh Kahdat {'k). Long. 14 mm., alt. 95 mm. Distribution: — Arakan Coast (Blanford), Calcutta (Lady Herschel), Madras (Henderson), Ceylon (Herdman), Bombaj' (Melvill & Abercrombie), the coast of Continental India (from Karachi to Panjim, Melvill & Standen). — Philippines (Cuming). Though the small valve which is at hand is somewhat worn, 1 have no doubt as to the correctness of the determination. G. F. Angas (Proc. Zool. Soc. London, 1867, p. 916. — J. C. Co.x, Exchange List of Land and Marine Shells from Australia, 222 126 1868, p. 24, No. 344) records M. Liizonica, Desli., from Porl Jackson and Botany Hay, bill Edg. Smith ' thinks that the specimens from these locahties are identical with M. piisilla, A. Ad. Mactra (Mactrinula) angulifera, Desh. Mactra angulifera, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 70, No. 37. — — — Reeve, Conchol. icon., VIII, Mactra, Sp. 83. — — — Weinkauff in Martini u. Chemnitz, Conchji. Cabin., XI lîd., 2 Abtli., p. 83, No. 87, pi. 28, fig. 5. Mactrinula — — Edü. Smith in Rep. Zool. Collect made during the Voyage of H. M. S. "Alert,' 1884, p. 101. ~ — — Hidalgo, Fauna malacol. de I. isl. Filipin.. II, p 56, No. 115. Mactra ovalina non Lamarck\ Reeve, Concliol. icon., VIII, Mactra, Sp. 66. South of Koh Chuen, 30 fathoms, shells ('/s). North of Koh Kahdat, 4—5 fathoms, coarse sand (1). West of Koh Kut, 30 fathoms, sand and mud (^'/a). Long. 7 — 31 mm. Distribution: — Singapore (shallow water, Sv. Gad), Mergui Archip. (E.v. Martens), Persian Gulf (E. v. Martens). — Philippines (Cuming). Edg. Smith " is of opinion that M. angulifera, Desh., is not specifically distinct from M. depressa, Spengler (Reeve), but in this he is probably mistaken. I have on PI. IV, Figs. 20—23 given figures of M. depressa, Spgl., drawn from Spengler's original specimens in the Zoological Museum of the University of Copenhagen. On comparing these figures with Reeve's figure of M. angulifera, Desh., one can soon be convinced that they are two distinct species (the valves of M. depressa are much thicker and more solid than those of M. angulifera). Reeve's description and figure of Spengler's depressa (Sp. 67) agree well with the original specimen. It is quite natural that Edg. Smith should doubt whether Reeve has correctly apprehended Spengler's form, as Spengler's description is not good, and his statement that Guinea is the locality is undoubtedly wrong. M. ovalina, Lam., has been greatly misapprehended by various authors; Weinkauff ■* records it (= falcata, Gould) from Puget Sound; Tate and May^ record it (^ depressa, Reeve) from Tasmania; G. B. SowERBY' records it (= depressa, Spgl.) from Durban in South Africa; d'Orbigny'' (= M. fragilis, Ch.) from Cuba, Brazil, and Patagonia; etc. It is fairly certain that these authors have had quite dilTerent species for investigation. ' Report on the Lamellibranchiata of the Challenger Expedition, p. 61. '' Report on the Lamellibranchiata of the Challenger PLxpedition. p. 57. 3 Martini u. Chkmnitz, Conchyl. Cabin., XI I5d., 2 Abth., p. 69, No. 70. ■• Proc. Linnean Society of New South Wales, 1901, p. 423. ^ Marine Shells of South Africa, Appendix, 1897, p. 22. Edü. Smith also records it (Journ. of Malaco- logy, 1904, p. 25) from Port Alfred, Cape Colonj'. •^ Mollusques de l'île de Cuba, 1853, II, p 222. List of the Shells of South America in the collect, of the British Museum, 1854, p. 56, No. 489. 127 223 Mactra (Mactrinula) Reevesi, Gray. Mactra Reeocsii, Gray, The Magazine of Natural History, I, 1837, p. 372. — — — Reeve, Conchol. icon., VIII, Macira, Sp. 92. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 2 Abtli., p. 82, No. Sr), pi. 28, fig. 2. Mactrinula Reevesii, Gray, Edg. Smith, Annals and Mag. Nat. Hist., 7 Ser., vol. 14, 1904, p. 9. East of Koh Chuen, 9—10 fathoms, shells ('/s). South of Koh Samit, 14 18 fathoms (1). Long. 40 mm., alt. 25 mm., crass. 13 mm. Distribution:— Malacca Strait. Off Chedubar (Aracan coast). — China. Lutr aria impar, Desh. Lutraria impar, Dfshayf.s, Proc. Zool. Soc. London, XXII, 1854, p. 70, No. 38. — — — Reeve, Conchol. icon., VIII, Lutraria, Sp. 10. West of Koh Kong, 10—15 fathoms (V/s). Long. 69 mm., alt. 26 mm. Distribution: — Moreton Bay, Australia (Strange). Of this characteristic species only one dead left valve, without epidermis, is found in the collections of the Danish Expedition to Siam. Lutraria maxima, Jonas. Lutraria maxima, .Ionas, Zeitschr. f. Malakozoologie, 1844, p. 34. — Molluskologische Beiträge (Abhandl. aus d. Gebiete d. Naturwiss., I, Hamburg 184(i), p. 110, No. 2, pi. 7, fig. 1 (non Lutraria maxima, Miduendorff, Malaeozoologia Rossiea, III, p. 582|. — — — Reeve, Conchol. icon., VIII, Lutraria, Sp. 11. — — — LiscHKE, Japan. Meeres-Conchyl., I, 1869, p. 138. — — — Dunker, Index molluscor. mar. Japon., 1882, p. 185. The sound of Koh Chang, 5 fathoms, soft clay ('/a). Long. 72 mm. Distribution: — China, Japan (Nagasaki). Lutraria curta, Desh. Lutraria curta, De.shayes, Proc. Zool. Soc. London, 1854, p. 71, No. 42. — — — Reeve, Conchol. icon., VIII, 1854, Lutraria, Sp. 5. — — — Hidalgo, Fauna malacol. de las isl. Filipinas, II, 1903, p. 59, No. 120. Between Koh Hin and Cliff Rock, 15 fathoms ('s). Distribution:— Aden (Shopland). — Philippines (Reeve). Only a small fragment of the left valve of a young individual has come to hand from the above locality, so the determination is somewhat uncertain. Raëta pulchella. Ad. and Reeve. (PI. IV, Fig. 24). Püromfia pulcliella, Ada.m.s & Reeve, Zoology of the voyage of H. M. S. Saniarang, MolIu.sca, 1848, p. 83, pi. 23, fig. 1. liaeta — — Ei>o. Smith, Lamellibranchiata of the Challenger Expedit., p. 56. 224 128 Raeta pulcheUa, Adams & Reeve, Hidalgo, Fauna malacol. de 1. isl. Filipinas, II, p. 58, No. 119. Mactra roslralis, Dkshayes, Proc. Zool. Soc. London, XXII, 1854, j). 09, No. ;V2. — — — Reeve, Concliol. icon., VIII, Mactra, Sp. 11 SI. Raeta — — Dunker, Index molluscor. mar. Japon., 1882, p. 185. The sound of Koh Chang, 5 fathoms, soft clay ('/■.>). Long. 25 mm., alt. 17 mm. Distribution:— Borneo, Philippines, China, Japan (Yokohama). The specimen from Koh Chang is larger than the individuals which have hitherto been described (long. 20 mm., alt. 14 mm.); it bears a very strong resem- blance to the form taken by R. Sturany^ at Ras Mallap in the Gulf of Suez in 50 fathoms, which he names Raëta bracheon; how far this species is synonymous with R. pulcheUa, Ad. and Reeve, I am not prepared to say. Unfortunately, my material consists only of a solitary, broken, left valve, of which I give a figure for future comparison. Raëta anatinoides, Reeve. Mactra Anatinoides, Reeve, Conchol. icon., VHI, 1854, Mactra, Sp. 123. The sound of Koh Chang, 3 — 5 fathoms, soft clay (''Is, partially fragments) N. of Koh Kong, 8 fathoms, mud (-/s). Long. 5 — 14 mm. (long. 14 mm., alt. 12 mm.). Distribution unknown. By comparisons in the British Museum, I have convinced myself that the specimens from tlie Gulf of Siam are really identical with R. anatinoides, Reeve, and not with R. pellicula, Desh., which, however, comes near to R. anatinoides, Reeve. Standella pellucida, Ch. Mactra pellucida, Chemnitz, Conchyl. Cabin., VI, 1782, p. 235, pi. 24, fig. 234. — — — Spengler, Skrivter af Naturhistorie-Selskabet, V Bd., 2 H., 1802, p. 123, No. 29. — — — Reeve, Conchol. icon., VIll, Mactra, Sp. 118. — — — Weinkauff in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 2 Abtli., p. 17, No. 14, pi. 5, fig. 1. Standella — — Hidalgo, Fauna malacol. de 1. isl. Filipin., II, p. 57, No. 117. — ■ (Merope, pellucida, Chemnitz, Melvill & Standen, Proc. Zool. Soc. London, 1906, p. 828. Mactra depressa, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 479, No. 29. — éd. 2, VI, p. lOG, No. 29. — — — Encyclop. method., II, 1830, p. 398. Coast of Lem Ngob (1 + ^/s). The strand off the MangroA'e at the station on Koh Chang, quite shallow water (6). Long. 7—48 mm. Distribution: — Bombay, extending southwards to Ratnagiri (Melvill & Standen). — Philippines. Melvill and Abercrombie write that dead specimens of the present species are common at Bombay; the two right valves from Lem Ngob are also from dead individuals, all the other individuals, which are small, were taken alive. ' R. Sturanv, Lamellibranchiata d. Rotlicn Meeres. Wien 1899, p 12, No. 10, pi. 3, figs. 1 ß. 129 225 Eastonia (Merope) Nicobarica, Gmel. Mactra niqosa Indiae orientalis, Chkmmtz, Coiicliyl. Cabin., VI, 1782, p. 238, pi. 24, fig. 237. nicobarica, Gmelin, Syst. Nat. ed. XIII, 1790, p. 3261, No. 24. Anaiinella Nicobarica, Gmelin, Tennant, Natural History of Ceylon, 1861, p. 389. Ltilrcirid Merope) Nicobarica, Gmelin, v. Martens, Journ. Linnean Society, Zoology, 1887, vol.21, p. 217, pi. 16, fig. 7. — — nicobarica, Gmelin, Thuhston, Ràmésvaram Island and Fauna of the Gulf of Manaar, 2 ed., 1895, p. 128. Mactra Aegyptiaca, Chemnitz, Conchyl. Cabin., XI, 1795, p. 218, pi. 200, figs. 1955— 56. Luiraria Eçjtjptiaca, Gray, Hanley, Catalogue of rec. biv. shells, p. 26, pi. 6, fig. 34. Mactra Ægyptiaca, Chemnitz, Reeve, Conchol. icon., VIII, 1854, Mactra, Sp. 112. Lutraria Aegiptiaca, — Issel, Malacologia d. Mar Rosso, 1869, p. 52. Merope Ægyptiaca, Gray-, Axgas, Proc. Zool. Soc. London, 1871, p. 100. Aegyptiaca, Chemnitz, Dunker, Index inolluscor. mar. Japon., 1882, p. 184. Mactra [Merope ægyptiaca, Chemnitz, Edg. Smith, Proc. Zool. Soc. London, 1891, p. 428, No. 222. Eastonia — aegyptiaca, — Pilsbry, Marine Mollusks of Japan, 1895, p. 120. Standella Ægyptiaca, Chemnitz, Shopland, Proc. Malacol. Soc. London, V, p. 177. Mactra reticulata, Spengler, Skrivter af Naturhistorie Selskabet, V Bd., 2 Hefte, 1802, p. 119. Lutraria Cheninitzii, Philippi, Zeitschr. f. Malakozool., 1849, p. 26, No. 99. Between Koh Riot and Koh Mesan, 3 — 5 fathoms, sand ('/a). Koh Kahdat, 1 fathom, sand ('/l'). Long. 18 — 43 mm. Distribution: — Singapore (shallow water, Sv. Gad), Mergui Archip., Nico- bars, Ceylon, Karachi, Aden, Red Sea (Chemnitz, Issel, Forskål (Mus. Univ. Hafn.), Sturany). — Java, Panay Isl. (Mus. Univ. Hafn.), Japan, Liukiu Isis., Lake Mac- quarie (New South Wales). As the original specimens of Chemnitz's "Mactra rugosa Indiae orientalis" and Mactra Aegyptiaca have been at my disposal, it has been possible for me to verify the reciprocal relation of these forms. Mactra rugosa Indiae orientalis has been described by Chemnitz from a specimen in Spenüler's collection, and was after- wards named Mactra reticulata by the latter. The figure given by Chemnitz is very bad, but Reeve's figure, Sp. 112, is an excellent illustration of the species, both as regards its form and its sculpture; the reticulata-îorm thus indicates the individuals with pointed posterior end and coarser radiating ribs, and the interstices between the ribs 2 — 3 times the width of the ribs. The other species M. Aegyptiaca has been figured fairly well by Chemnitz ; it comprises the forms with oval shells, and finer, more closely set radiating ribs; but between these two extremes there is an extensive series of intermediate forms, which I have before me, and which distinctly show that it is same species which varies. I have also at hand that small characteristic form which Ed. v. Martens describes and figures from "King Island, mud-bank ex- posed at spring-tide;" my specimen was taken at Singapore in shallow water, it is only a thin-valved, littoral, local form of E. Nicobarica Gm., ornamented with rather slight and delicate ribs. 1). K. I). ViilcnsU. Sclsk. .Skr., 7. Ilielilie. n:iliir\ insk. i)|; miithem. AW. V. 3. 29 226 130 Caecella Cumingiana, Desh. Cœcella Cumingiana, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 334, No. 78. — — -- Hidalgo, Fauna malacolog. d. I. isl. Filipinas, II, p, 60, No. 123. Koh Chang (14). Coast of Koh Chang (1). Long. 10—26 mm. Distribution:— Philippines. I have at my disposal some specimens of C. Cumingiana, Desh., from the Philippines which were contributed by Cuming himself; they are somewhat larger than the specimens from the Gulf of Siam, but otherwise exactly correspond with them. The epidermis in the small individuals (measuring as much as 23 mm. in length) is pale yellow, while in older individuals it is brownish. It will undoubtedly be proved in the future that the series of species established by Deshayes of the genus Caecella, can be considerably reduced. Fam. Veneridae. Cytherea (Meretrix) meretrix L. Venus Meretrix, Linné, Syst. Nat., ed. X, 1758, p. 686, No. 102. — ed. XII, p. 1132, No. 127. — Mus. Ludovicæ Ulricæ reg., p. 501, No. 60. Cytherea meretrix, Linné, Lischke, Japanische Meeres-Conchylien, I, pp. 122 — 26. Meretrix — — Dautzenberg et Fischer, Journ. de Conchyl., vol. 53, 1905, p. 216. Venus lusoria, Chemnitz, Conchyl. Cabin., VI, 1782, p. 337, pi. 32, fig. 340. Meretrix — — Römer, Monogr. d. Molluskengatt. Venus, 1, p. 30, pi. 12, fig. 1; pi. XI, flgs. 1—2. Cijtiierea petechialis, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 561, No. 2. — éd. 2, VI, p. 299, No. 2. Meretrix — — Römer, Monogr. d. Molluskengatt. Venus, I, p. 29, pi. 9, fig. 1. Venus zonaria, — Hist. nat. d. anim. s. vert., V, 1818, p. 562, No. 5. — éd. 2, VI, p. 299, No. 5. — impudica, — Hist. nat. d. anim. s. vert., V, 1818, p. 561, No. 3. - éd. 2, p. 299, No. 3. North coast of Koh Chang (1). Long. 51 mm. Islands in the Gulf of Siam (M. petechialis, Lam. — L. Morlet). "Siam" (M. impudica, Lam., M. zonaria, Lam. — E. v. Marten.s). Distribution:— Singapore, Salang (Malacca), Nicobars, Ceylon, Bombay, Aden. — Annam, Tonkin, China, Formosa, Japan, Liukiu Isis., Philippines, Borneo, Java, Timor, Moluccas. ("Mazatlan," Carpenter ; without doubt the determination is erroneous). The specimen from Koh Chang belongs to the form zonaria, Lam. The many different species which have been established by Lamarck and other authors on the basis of the present species, have for a long time rendered its determination difficult, and Lischke (loc. cit.) was the first to demonstrate, and that correctly, that all these forms belong to the same species. In spite of this, many later authors have persisted in maintaining the varieties as species, a view which is quite unten- able when larger series and specimens in various ages are at hand for investigation. 131 227 HiiJAi.r.o (Obras malncolôgicas, I, Toni. 2, 19((3, p. 182) has enuineraied 10 dUTerent colour-variations of Cijth. nieretrix from the Philippines. Dautzenbekg and H. Fischer (Journ. de Conchyl., vol. 53, 1905, pp. 216 — 20) enumerate the synonyms of this well-known species, which form a long list. Cytherea (Meretrix) lyrata, Sow. Cijlherœa lyrata, Sowerby, Thesaurus Conchj'l, II, 185.'), p. 621, pi. 129, fig. (il. Cytherea — — Keeve, Conchol. icou., XIV, Cytlierea, Sp. 13. — (Meretrix) lyrata, Sowerby, Römer, Monogr. d. Moll. Venus, I, p. 36, No. 11, pi. 11, fig. 3. Meretrix lyrata, Sowerby, Morlet, Journ. de Conchyl., vol.37, 1889, p. 168, No. 59. — — — Fischer, Catalogue de Moll, de I'lndo-Chine, p. 233. Islands in the Gulf of Siam. (Morlet, loc. cit.). Distribution:— Cambodge, Cochin China, Tonkin, Philippines. The present large species, strangely enough, was not collected by the Danish expedition. Cytherea (Caryatis) hebraea, Lam. Cytherea hehrira, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 568, No. 30. — éd. 2, VI, 1835, p. 308, No. 30. — — — Delessert, Recueil de coquilles décr. p. Lamarck, 1841, pi. 8, fig. 6. (Caryatis) hebraea, Lamarck, Römer, Monogr. d. Molluskengatt. Venus, I, p. 116, No. 44. Circe Hebrœa, Lamarck, Reeve, Conchol. icon., vol.14, 1863, Circe, Sp. 34. — hebrœa, — Morlet, Journ. de Conchyl., vol. 37, 1889, p. 169, No. 64. Cytherea (Caryatis) hebrœa, Lamarck, Edg. A. Smith, Laraellibranchiata of the Challenger Expedition, 1883, p. 138. Islands in the Gulf of Siam (Morlet, loc. cit.). It is with doubt that I refer a small (8 mm.) single valve from the coast of Koh Kahdat to the present species. Distribution: — Ceylon, Persian Gulf, Aden, Red Sea, Seychelles, Natal. — Philippines, Torres Strait, New South Wales. It is doubtful whether all the authors who have recorded the present species from the above-mentioned localities have had the true Cyth. hebraea, Lam., before them. It is recorded by several authors (e. g. H. Krebs, O. Mörch, C. T. Simpson, W. H. Dall, etc.) from the West Indies, but these records are due to its having been confounded with Cyth. varians, Hani. Cytherea (Caryatis) affinis, Gmel. var. inflata, Sow. Cytherœa inflata, Sowerby jun., Thesaurus Conchyl., II, 1855, p. 637, pi. 133, figs. 127—28. Dione — — - Reeve, Conchol. icon., XIV, Dione, Sp. 37. — — — - Deshayes, Catalogue of the Concliifera in Brit. Mus., 1853, p. 65, No. 28. Cytherea afßnis, Gmelin var. inflata, Sowerby, Pfeiffer in Martini u. Chemnitz, Conchyl. Cabin., XI, 1 Abth , pp. 24—25, — (Caryatis) affinis, Gmelin var. inflata, Sow., Römer, Monogr. d. Molluskengatt. Venus, 1, p. 105, pi. 33, figs. 6-7. Callisla inflata, Sowerby, Donker, lnde.\ moll. mar. Japon., 1882, p. 201. Pitaria — — Hedley, Proc. Liun. Soc. New Soutli Wales, vol. 31, 1906, p. 460. 29* 228 132 Between Koh Mesan and Koli Chuen, 25—38 fathoms, stones and stiells ('/a). S. of Koh Chuen, 30 fathoms, shells ('/a). Koh Mak, sandy coast ('/s). S. of Koh Mak, 5 — 6 fathoms (^/s). N. of Koh Kahdat, 4—5 fathoms, sand (1). Koh Kahdat, 1 fathom, sand (-/a). Long. 8 — 34 mm. Distrihution: — Nicobars, Andamans, Ceylon, Mauritius, Reunion, Rodriguez. — Philippines, Japan, Moluccas, Torres Strait, Mast Head Reef (Queensland), Port Curtis (Australia), Lifu. Cytherea (Caryatis) striata, Gray. Chione striata, Gray, The Analyst, VIII, 1838, p. :i06. Cytherica citrina (non Lamarck), Sowerby, Thesaurus Conchyl., II, p. 63(i, pi. 13"2, figs. 117 — 18. Dione striata, Gray*, Reeve, Conchol. icon., XIV, Dione, Sp. 44. Cytlterca {Canjatis) citrina, Römer, Monogr. d. Molluskengatt. Venus, I, p. 100, pi. 27, fig. 2. Callisia citrina, Rochebrune, Bull, de la Soc. Philomat. dc Paris 1881, (Reprint, p. 15, No. 48|. Mcretrix {Pitar) citrina, FrscHER, Catalogue d. Moll, de I'lndo-Chine, p. 233. North coast of Koh Chang ('/2). Long. 36 mm. Distribution: — Poulo Condor, Philippines, Formosa, Sulu Isis., Kei Bandan, Jobi Isl. (Geehvinck Bay). C. striata. Gray, has always been referred to C. citrina, Lam., but sufficient proof that it is not that species appears to me to be given by Lamarck's diagnosis ("testa cordata-trigona") and by Delessert's figure (PI. 8, Fig. 8) of Lamarck's original specimen. Hidalgo' has arrived at the same conclusion with regard to the speci- mens from the Philippines. H anle y's C. s/ria/a, Gray? ^ from the "River Gambia" is not Gray's species of that name, but is identical ^vith C. citrina, Lam. The indi- vidual from the Gulf of Siam which I have before me exactly agrees with Romer's description and figure (loc. cit.) of C. citrina (^ C. striata, Gray). The true C. citrina, Lam., occurs around Australia, and is easily distinguished from striata by its more triangular form and by its posterior end being considerably more pointed as com- pared with the more truncated form of striata. Cytherea (Caryatis) minuta, Koch. (PI. IV, Figs. 2.'')- 27). Cytljcrea minuta, Koch, Philippi, Abbild, u. Beschreib, neuer od. wenig gekannt. Conchylieu , I, 1845, p. 22 (200), Cytherea, pl. 3, fig. 8. — {Caryatis) minuta, Koch, Römer, Monogr. d. Molluskengatt. Venus, I, p, 124, pl. 33, fig. 1. Dions minuta, Koch, Deshayes, Catalogue of the Conchifera in Brit. iMus., I, p. 73, No. 58. Koh Kram, 30 fathoms (1). Koh Chuen, 10—15 fathoms (•■/a). W. of Koh Chuen, soft clay and mud (*»/:i). W. of Koh Chang, 30 fathoms (»/a). W. of Koh Chang, 20 fathoms, mud (3). The strand off the mangrove at the station on Koh ' Obras malacolôgicas, I, Tom. 2, 1003, p. 198. - Sowerby, Thesaurus Conchyl., I. p. (i37, pl. 132, tig. 113. 133 229 Chang {' .). Belween Fvoh Chuen and Koh Chang, 15 fathoms, nuul ('2). BeUveen Koh Kahdat and Koh Kiit, 6—10 fathoms, clay mixed with sand (fi). W. of Koh Kilt, 15 fathoms, mud (2). W. of Koh Kut, 30 fathoms, sand and mud ("/:!). S. of Koh Kut, 17-20 fathoms, mud (1). S. of Koh Kahdat, 8—10 fathoms, mud ('/:i). E. of Koh Mak, 20 fathoms, mud (4). W. of Koh Kut, 15 fathoms, mud (1). Long. 3— 16 mm. Distribution: — Meigui Archip. (E. v. Martens). The figure bj' Römer (loc. cit.) is not good, flierefore I have figured some of the specimens from the Gulf of Siam. E. v. Martens was the first (19, lie records T. radiata, Anton (Cheinn., VII, fig. 439), from Seychelles. I), K, I), Viilensk, Selsk. Skr., 7. Række, naturviilensk. ok matliem, AftI, V. 3. 31 242 146 Chione (Omphaloclathrum) marica L. (Sow.). (PI. V, Figs. 1-4). Venus marica, Linn.kus. Sowerby, Thesaurus Concliyl., II, p. 719, No. 47, pi. 157, fig. 108 Between Koh Riot and Koh Mesan, 3-5 fathoms, sand ('/a). N. of Koh Kalidal, 4 -5 fathoms, coarse sand (2). W. of Koh Kul, 15 fathoms, mud (1). Long. 8 — 19 mm. Distribution ? Edg. Smith says in the report on the Lamellibranchiata of the Challenger Expedition (p. 125) "This species {Venus (Chione) marica L.) is so well known that it is unnecessary to give further references than those above mentioned." This may be true as regards the name, because from as far back as the times of Linné and Chemnitz it has constantly been recorded and mentioned from many localities all over the globe; but a comparison of the descriptions and figures given by Linné, Chemnitz, Sowerby, Reeve and others leaves an impression of great uncertainty with regard to the characteristics and limits of the species. For instance, it appears to me that Linné-Chemnitz's species can scarcely be identical with Sowerby's Ch. marica, Thes. Conchyl. fig. 108 (Edg. Smith's species Ch. recognita is undoubtedly also frequently confused with Ch. marica). All the individuals from the Gulf of Siam agree precisely with Sowerby's figure 108, but how far that is identical with, or is a form of Linné's Ch. marica is perhaps doubtful. I have given a figure of the specimens from the Gulf of Siam to fix the form for future comparisons. The specimens from Moltke's collection, from which Chemnitz had his figures 282 — 84 made (PI. 27 in the "Conchylien Cabinet". Figs. 285— 86 scarcely belong here), exist no longer in the Moltke collection included in the Zoological Museum of the University of Copenhagen, so I have not been able to compare Chemnitz's specimens with mine from the Gulf of Siam. Sturany' is inclined to regard "Venus Romeriana, Issel," from the Red Sea, as a young form of Ch. marica L. Chione (Omphaloclathrum) recognita, E. Sm. Venus (Cliione) recognita, Eud. Smith, Keport on the Lamellibranchiata of the Challenger Expedition, 1885, p. 125, pi. 3, fig. 5. — Marica, Reeve p. p., Concholog. icon., XIV, 1863, Venus, fig. 104 a (non 104 b and c). Koh Kahdat, sand, 1—5 fathoms (70). N. of Koh Kahdat, 4-5 fathoms, sand (14). Koh Mak, sandy coast (-/a). S. of Koh Mak, 5-6 fathoms (2). W. of Koh Kut, 15 fathoms, mud (4). Long. 6-5 — 20 mm. Long. 20 mm., alt. 15 mm., crass. 10 mm. — 17 mm., — 135 mm., — 85 mm. Distribution:— Suvativa Atoll (Maldive Archip.), Philippines. — Mast Head Reef, Queensland (Hedley). ' Lamellibranchiaten d. Rothen Meeres, 1899, p. 27. 147 243 This beautiful species is doubtless often confused with Ch. marica L., which it somewhat resembles, and it is probably more widely distributed than is at present known. The specimens from the Gulf of Siam vary greatly both in outline and in colour, most of them are not as high as is shown in Smith's figure (but the measurements given in the text agree fairly well with those of my specimens), and resemble more closely Reeve's figure (loc. cit.), which I think ought to be referred to the present species. The coloration varies exceedingly, there are scarcely two specimens which are alike in regard to painting; pale-red, white, and yellow individuals occur, with brown or red zigzag-lines, spots and rays, and many other paintings. In the interior of the valves the colour varies from entirely white to dark lilac. As the lamellæ upon the posterior end ai-e often only slightly conspicuous, I think that Adams's and Reeve's species Venus cost elli fer a is nothing butan individual of Ch. recognita, Sm., with worn or only slightly developed lamellæ; the other distinguishing characters given for V. costellifera are also not very good. H. A. Pii.sBRY, ' under the name of Ch. bizenensis, has described a very closely allied form from Japan. Chione (Omphaloclathrum) subnodulosa, Hani. PI. V, Fig. 5). Venus subnodulosa, Hanlky, Proc. Zool. Soc. London, XII, 1844, p. 160. — — — Catalogue of rec. biv. shells, p. 3G0, pi. 16, fig. 19. Chione — — Dkshayks. Catalogue of the Conchifera in Brit. Mus.. I, 185.3, p. 143. Venus — — Reeve, Conchol. icon., XIV, Venus, Sp. 102. Off Koli Kam, 10 fathoms, gravel (-/i;). Between Koh Mesan and Cape Liant, 5—9 fathoms (8). Gulf of Rayong, 7 — 10 fathoms, sand, mud (13). S. of Koh Samit, 20 fathoms, mud (21). Off Tung Kaben, 6 fathoms, mud mixed with sand (2). S. of Koh Mak, 5 — 6 fathoms (^'a). N. of Koh Kahdat, 4—5 fathoms, coarse sand (8). Koh Kahdat, 1—5 fathoms, sand (5). Between Koh Kut and Koh Kahdat, 6 — 10 fathoms, shells, and clay mixed with sand (25). W. of Koh Kut, 15 fathoms, mud (4). W. of Koh Kut, 30 fathoms, sand, mud ('/a). Long. 3 — 19 mm. Long. 19 mm., alt. 13 mm., crass. 10 mm. Distribution:— Singapore (2—3 fathoms, coral-reef (^/s), Danish Exp. to Siam), Philippines (Han'ley), Thursday Island (v. Martens), Torres Strait (Melvill & Standen), Mast Head Reef, Queensland (Hedley). This species varies rather considerably, e. g. with regard to the distances between the concentric lamellæ. The coloration is also, as in Ch. recognita, Sm., very variable; usually the primary colour is light or yellowish, with brown rays or stripes; in the Gulf of Siam, however, entirely white specimens, with dark brown lunules, were taken. The interior of the valves is either quite white or ornamented with dark spots and rays. ' Proceed. Acad. Nat. Hist. Philadelphia, vol. 56, 1904, p. 553, pi. 41, figs. 1—2. 31* 244 148 Chione (Timoclea) imbricata, Sow. Ve;iiis imbricata, Sowerby, Thesaurus Conchyl., Il, 1855, p. 715, pi. 156, figs. 81-82. — — — Reeve, Conchol. icon., XIV, Venus, Sp. 118. Chione — — Römer, Malakozool. Blätter, XIV, 1867, p. 59, No. 46. Venus — — Fischer, Catalogue d. Moll. de I'Indo-Chine, p. 273. — Cochinensis, — Thesaurus Conchyl., II, 1855, p. 716, pi. 156, figs. 79—80. Chione — — Römer, Malakozool. Blätter, XIV, 1867, p. 60, No. 47. "Gulf of Siam" {L. Morlet). Distribution:— Mergui Archip., Ceylon, Red Sea (?). — Cochin China, China, Philippines. This species does not occur in the collections made by the Danish Expedition. Chione (Timoclea) scabra, Hani. Venus scabra, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 161. — Catal. of reo. biv. shells. Append., p. 361, pi. 16, fig. 24. _ _ _ Sowerby, Thesaurus Conchyl., II, 1855, p. 718, No. 45, pi. 157, figs. 101— 2. Venus — — Reeve, Conchol. icon., XIV, Venus, Sp. 97. Chione — — Römer, Malakozool. Blatter, XIV, 1867, p. 58. Venus (Chione) scabra, Hanley, Edg. Smith, Rep. on the Lamellibranchiata of the Challenger Exped., p. 124. — — — — Dautzenberg et Fischer, Journ. de Conchyl., vol.54, 1906, p. 217. Chione scabra, Hanley, Melvill & Standen, Proc. Zool. Soc. London, 1906, p. 835. — micra, Pilsbry, Proceed. Acad. Nat. Hist. Philadelphia, vol.56, 1904, p. 552, pi. 41, figs. 4 — 5. Very common; many specimens were taken everywhere between Koh si Chang and Koh Kong, in 3 — 20 fathoms, on a muddy and clayey bottom. Long. 2 — 16 mm. Distribution: — Poulo Penang ("Galathea" Exped.), Mergui Archip., Gulf of Manaar, Madras, Persian Gulf, Gulf of Oman. — Annam, Phiüppines, Japan, Mast Head Reef (Queensland). The present species varies considerably both in outline and in sculpture. Thus, Ch. micra, Pilsbry, is only a younger individual with fewer ribs; several specimens of similar forms (showing even transitional stages to the type-form) are at hand from the Gulf of Siam. Chione (Timoclea) Siamensis n. sp. (PI. V, Figs. 6-7i. This species is roundly trigonal, moderately convex, v^'hitish, longer than high, and the posterior end is elongated and rather pointed. The umbo is situated in the anterior half of the valve and the ventral margin is slightly convex. The sculpture consists of strong, parallel, concentric ridges crossed by close-set radiating ridges, and at the points of contact rounded, bead-like granules are formed. These radiating ribs differ in thickness and are placed at different distances apart; thus at the anterior end there are 3 — 4 strong and prominent ribs, then follow, over the 149 245 whole of the middle portion, numerous close-set, fine, regularly-arranged ribs, which fork towards the ventral margin; then, towards the posterior end, 6 — 9 strong ribs occur, which are less broad than the interstices between them; where these posterior radiating ribs meet the concentric ribs, the bead-like granules which occur upon the rest of the shell become strong scales. On the somewhat elongated lunule only slightly granulated, radiating ribs are found ; the large oblong area is quite smooth, without any ribs. The interior of the valves is white and somewhat glossy. There are three teeth in each valve, the central one in the left valve and the central and posterior in the right are tripartite at the top; the posterior tooth in the left valve is only slightly developed. The inner margin is finely crenulated all the way round, but most strongly at the ventral margin, and most finely and closely at the lunule-margin. The palliai sinus is short. Long. 8 mm., alt. 6 mm., crass. 45 mm. West of Koh Kut, 30 fathoms, sand and mud ("/s). This new species is most nearly allied to Ch. lionata. Smith, from which it is, however, easily distinguished by its peculiar sculpture. Chione (Timoclea) lionata, E. Sm. (PI. V, Figs. 8— l(t). I'eni/s [Chione] lionata, Edg. Smith, Report on the Lamellibranchiata of the Challenger Exped., 1885, p. V2G, pi. 3, fig. 7. Between Koh Rin and Cliff Rock, 15 fathoms f/s). Koh Kram, 30 fathoms (a/a). Off Koh Kam, 10 fathoms, gravel ('/a). E. of Cape Liant, 9 fathoms, shells (Va). S. of Koh Samit, 20 fathoms, mud ('/a). S. of Koh Chuen, 30 fathoms, shells (15). Between Koh Chuen and Koh Chang, 15 fathoms, mud (-'/a). S. of Koh Kahdat, 8—10 fathoms, mud (^/a). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (17). S. of Koh Kut, 17—20 fathoms, mud (*/a). W. of Koh Kut, 15 fathoms, mud (-/a). Long. 8 mm., alt. 65 mm., crass. 5 mm. Distribution: — Singapore, shallow water (Danish Exp. to Siam). — Amboina, S. of New Guinea (Challenger). I have compared my specimens with Edg. Smith's original types in the British Museum ; they exactly agree with his specimen from Amboina (which he regards as a variety), while his specimens from New Guinea are somewhat different. Judging from the large quantity of material at hand from the Gulf of Siam it appears, however, that the species varies considerably. As may be seen from the measurements given above, the specimens from the Gulf of Siam are larger than Smith's from the Challenger Expedition. As Smith's figure is not very good I have here given a new figure. Chione (Antigona) lamellaris, Schumacher. Antigona lamellaris, Schumachek, Essai dun nouv. systime d. habitat, d. vers testaces, 1817, p. 155, pi. 14, fig. 2. Venus — — MARTiNiu.CHi;MMTZ,Conchyl.Cabin.,XI,l Abth., p.l42. pl.8, figs. 10— 11. 246 150 Venus (Antigona) lamellarix, Schumachi:!!, Edo. Smith, Rep. on tlie Lamellibraiicliiata of the Challenger Exp., p. 121. — lamellaris, Schumacher, Crosse et Fischer, Journ. de Conchyl., vol. 4U, 1892, p. 7ü. Dosina Lamarckii, Gray, The Analyst, VIII, 1838. p. 308. Clüone — — RÖMER, Malakozoolog. Blätter, XIV, 1867, p. 39. Venus — — Reeve, Conchol. icon., XIV, Venus, Sp. 39. — — — SowERBY, Thesaurus Conchyl., II, p. 707, pl. 153, figs. 20— 21. — nodulosa, Sowerby jun., Thesaurus Conchyl., II, p. 708, pl. 153, fig. 10. — canceUata var., Chemnitz, Conchyl. Cabin., VI, 1782, p. 310, p. 29, figs. 300— 7. S. of Koh Chuen, 30 fathoms, shells (3). E. of Cape Liant, 9 fathoms, shells (2). Gulf of Rayong, 7—10 fathoms, mud (5). W. of Koh Kut, 15 fathoms, mud (1). Long. 11—40 mm. The Gulf of Siam, west coast of Cambodge (Pavie). Distribution: — Singapore, Tranquebar, Ceylon and Gulf of Manaar, Aden (Shopland). — Philippines, China, Japan, North, East and West Australia (Brazier), Viti Isis. Chione reticulata L. Venus reticulata, Linné, Syst. Nat., ed. X, 1758, p. 687, No. 110. — ed. XII, p. 1133, No. 134. — Mus. Ludov. Ulricæ reg., 1764, p. 503, No. 64. — — — Chemnitz, Conchyl. Cabin., VI, p. 367, pi. 36, figs. 382-83. — — — Sowerby, Thesaur. Conchyl., 11, p. 706, pl. 153, figs. 11 — 13. — — — Reeve, Conchol. icon., XIV, Venus, Sp. 34. — — — Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 1 Abth., p. 143, No. 15, pi. 10, figs. 1-2. Chione — — Römer, Malakozoolog. Blätter, XIV, 181)7, p. 30, No. 12. Venus {Antigona) reticulata, Linné, E. v. Martens, The Journal of the Linnean Soc, Zoology, vol. 21, 1887. p. 212. — corbis, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 585, No. 4. — éd. 2, VI, p. 337, No. 4. — — — MoRLET, Journ. de Conchyl., vol. 37, 1889, p. 170, No. 68. — — — Fischer, Catalogue d. Moll, de I'lndo-Chinc, p. 233. — reticulata, Linné, R. Bullen Newton, The Geological Magazine, New Ser., Dec. IV, vol. 7, 1900, p. 553, pl. 21, fig. 2. Islands in the Gulf of Siam (L. Morlet, loc. cit.). Distribution: — Mergui Archip., Nicobars, Ceylon, Addu Atoll and Hululu Isl. (Maldive Archip.), Persian Gulf, Aden, Red Sea, Madagascar. — Philippines, Japan, Moluccas, Torres Strait, New Caledonia, Marianne Isis., Lifu, Viti Isis., Society Isis., Marquesas Isis., Paumotu Isl. Strangely enough, the Danish Expedition to Siam collected no specimens of this species. Chione (Circomphalus) calophylla, Phil. Venus caloplxylla, Philippi, Archiv f. Naturgeschichte hisg. v. Wiegmann, Il Jahrg., 1 Bd., 1830, p. 229, pl. VIII, lig. 2. — calopliyla, Hanley, Sowerby, Thesaurus Conchyliorum, II, 18Ô5, p, 724, pl. 160, fig. 176. — calophylla, Philippi, Reeve, Conchol. icon., XIV, Venus, Sp. 114. — — — Martini u. Chemnitz, Conchyl. Cabin., XI, 1 Abth., p. 208, pl. 33, flgs. 13 — 15. — {Chione) calophylla, Philippi, Eno. Smith, Lamellibranchiata of the Challenger Exped., p. 122. Anaitis calophylla, Philippi, Hidalgo, Obras malacologicas, I, tom. II, 1903, p. 294, No. 387. 151 247 S. of Koh Samit, 20 fathoms, mud (1). W. of Koh Chuen, soft clay and mud (^/ä). Between Koh Chuen and Koh Chang, 15 fathoms, mud (1). N. and W. of Koh Chang, 10—20 fathoms, mud (6). S. of Koh Bidang, 9 fathoms, mud (4). Between Koh Kahdat and Koh Kut, fi- 10 fathoms, mud, clay mixed with sand, and shells (12). S. and W. of Koh Kut, 15-20 fathoms, mud (9). Long. 2 — 36 mm. Distribution:— Singapore (Danish Exp. to Siam : one specimen in 2 — 3 fathoms; Sv. Gad: 5 specimens in shallow water), Mergui-Archip., Andamans, Madras, Gulf of Manaar. — Philippines, China, Japan, Thursday Isl. (Semon), New- Guinea, Torres Str., North Australia, Sydney. Note. The Danish Expedition to Siam obtained two specimens, and Mr. Sv. Gad several specimens of Chione (Circomphalus) foliacea, Phil., at Singapore. Chione (Circomphalus) isabellina, Phil. Venus isabellina, Phii.iim'i, Zeitschr. f. Malakozoologie, V, 1848, p. 188 (it is due to a misprint, wliicli is corrected in tlie register, that tliis species is called isabillnia). — — — Abbild, u. Beschreib, neuer od. wen. gek. Conchyl., III, 1851, p. 83, No. 5, pl. X, flg. ö (Venus). — — — Mautini u. Chemnitz, Conchyl. Cabin., XI Bd., 1 Abtii., p. 194, pl. 'J.'i, fig. 9. — — — Reeve, Conchol. icon., XIV, Venus, Sp. 112. — — — P. Fischer, Catal. d. Moll, de I'Indo Chine, p. 233. — Dysera, Chemnitz, Conchyl. Cabin., VI, 1782, p. 297, pl. 28, figs. 291— 92. — — — SowERBY, Thesaurus Conchyl., II, p. 723, pl. 157, Hg. 119. Anuitis isabellina, Philii'fi, Hidalgo, Obras malacologicas, I, tom. II, 1903, p. 291, No. 385. The strand off the Mangrove at the station on Koh Chang, very shallow water (4). The coast of I-,em Ngob (2). Long. 16—26 mm. Distribution: — Bombay. — Annam, China, Japan, Philippines, Port Curtis, Sydney (W. Denison, Madras Museum). Melvill & Standen say regarding this species:' "Perhaps best treated as a varietj' of A. foliacea" {Anaitis foliacea, Philippi). Chione (Ventricola) toreuma, Gould. Venus toreuma, Gould, Proceed, of the Boston Soe. Nat. Hist, III, 1850, p. 277. — Otia Conchologica, p. 84. — — — Reeve, Conchol. icon., XIV, 1863, Venus, Sp. (i4. — — — LiscHKE, Japan. Meeres-Conchyl., I, 1869, p. 121, II, p. 108. — — — Report on the zool. collect, made during the voyage of "Alert," 1884, p. 93. — tourema, — Hidalgo, Obras malacologicas, I, tom. II, 1903, p. 288, No. 382. — Jukesi, Deshaves, Catalogue of the Conchifera in the Coll. of the British Mus., I, 1853, p. 100, No. 3. — — — Martini u. Chemnitz, Conchyl. Cabin., XI, 1 Abth., p. 217, pl. 35, figs. 7-9. Chione (Venlricola) Jukesi, Deshayes, Römer, Malakozool. Blätter, XIV, 1867, p. 123. Venus crebrisulca, Sowerhy, Thesaurus Conchyl., II, 1855, p. 728, pl. 161, figs. 187—89 (non LamarckI. — sculpta, Deshayes, Reeve, Conchol. icon., loc. cit., Sp. 5 (fide Edg. Smith). ' Proe. Zool. Soc. London, 1906, p. 834. 248 152 Koh Kram, 30 fathoms ('/s). North side of Koh Mesan, 10—15 fathoms, stones (2). Koh Chueii, 10—15 fathoms (Va). Long. 10 — 29 mm. Distribution: — Ceylon and Gulf of Manaar, Huluki Isl. (Maldive Arcliip.). — Philippines, Japan, Torres Strait, North and East Au.stralia, Funafuti (Ellice Isis.), Mangsi Isl., Sooloo-Sea. The present species is recorded (with doubt) from Mauritius and Cargados, and probably erroneously by J. G. Cooper from California. I doubt whether Chione embrithes, Melvill and Standen, ' can be maintained as a distinct species. Dosinia trigona, Reeve. Artemis trigona, Reeve, Conchol. icon., VI, 18.50, Artemis, Sp. 4'2. Cythercea — — Soweuby, Thesaurus Conchyl., II, p. 033, pi. 133, fig. 120. Artemis — _ _ loc. cit., II, p. O,");), pi. 141, fig. 2U. Dosinia — — Römer, Monographie d. Molluskengatt. Dosinia, 186'2, p. 20, pl. 4, fig. 5. The strand off the Mangrove at the station on Koh Chang (2). Coast of Lem Ngob (-'/a). Long. 20—39 mm. Long. 35 mm., alt. 37 mm., crass. 27 mm. — 31 mm., — 32 mm., — 20 mm. Distribution: — Gulf of Manaar (Thurston). Reeve's statement (repeated by Deshayes, Sowerry, Römer and others) that this species was found in the Red Sea has not hitherto been confirmed. Dosinia laminata, Reeve. Artemis laminata. Reeve, Conchol. icon., VI, 1850, Ailemis, Sp. 41. — — — SowEiiBY, Thesaur. Conchyl., II, p. 674, No. 71, pl. 144, figs. 80 — 87. Dosinia — — Römer, Monogr. d. Moll. Dosinia, 1862, p. 62, No. 72, pi. 16, fig. 2; pl. 10, fig. 3. — — — Martini u. Chemnitz, Conchyl. Cahin., XI, 1 Abth., p. 104, pl. 26, figs. 10 — 12. — — — Hidalgo, Obras raalacologicas, I, tom. II, 1903, p. 305, No. 398. Off Tung Kaben, 6 fathoms, mud mixed with clay (1). W. of Koh Chang, 20 fathoms, mud (2). S. of Koh Kahdat, 8-10 fathoms, mud (5). Koh Kahdat, 1 — 5 fathoms, sand (1). Between Koh Kut and Koh Kahdat, G— 10 fathoms, clay and sand (2 + »/2). S. of Koh Mak, 5-6 fathoms (1). East of Koh Mak, 20 fathoms, mud (3 + 1/2). W. of Koh Kut, 15 fathoms, mud (20). Long. I'/a- 34 mm. (Long. 34 mm., alt. 34 mm., crass. 18 mm.). Distribution: — Andamans, Red Sea (pleistocene). — Philippines, China, Japan. Almost all the individuals from the Gulf of Siam were full of clay between the transverse ribs owing to the clayey soil in which they had been living. ' Journal of the Linnean Society, Zoology, vol. XXVII, p. 195. 153 249 Dosinia exasperata, Phil. Cytherea iArtemis) e.vasperata, Phii.ippi, Abbild, u. Beschreib, neuer od. wen. gelt. Conchyl., Ill, 1847, p. 24 (36), pi. 8, fig. 4. Artemis e.vasperata, PHii.ii'Pt, Sowerby, Thesaur. Conchyl., 11, p. R70, No. 55. pi. 143, fig. 62. — — — Reeve, Conchol. icon., VI, Artemis, Sp. 21. Dosinia — — Hidalgo, Obras malacologicas, 1, tom. 11, 1903, p. 311, No. 407. The sound of Koh Chang, 5 fathoms, soft clay (/:!). W. of Koh Kut, 15—30 fathoms, mud (•''a). Long. 8 — 30 mm. Distribution:— Coromandel Coast (?), Karachi, Mekran Coast. — Philippines. Several authors have connected Dosinia prostrata with the present species; but, as far as I can see, the two species have nothing to do with each other. In the Zoological Museum of the Universitj' of Copenhagen Spengler's specimen of Dos. prostrata L. is labelled: "Venus prostrata Lin. Sp. 137. Chemn. Tom. 6, fig. 29S, Tranquebar." It exactly agrees with the figures in Hanley's Ipsa Linnæi Conchyl., PI. 1, Fig. 7; in Encyclop. method., PI. 277, Fig. 1; in Reeve, Conchol. icon., Sp. 23; in • Hanley, Monogr. (Sowerby, Thes. Conchyl.), PI. 144, f^ig. 80, and with the description in Chemnitz, Conchyl. Cabin., VI, p. 302. ' It may probably be assumed that Spengler's specimen is correctly determined, at any rate it undoubtedly corresponds with Chemnitz's view of prostrata;'- but Spengler's prostrata and Philippi's exasperata diiïer widely, the outline in prostrata being angular, which (especially in full-grown individuals) gives a squarish appearance to the shell; this is compressed (like Circe scripta L.), and the lunule is elongated: v.'hile in Dos. exasperata the outline is almost circular, the shell is more arched, and the lunule is smaller and cordate; and as regards the sculpture, the transverse ribs are more close-set and much finer. Dosinia exasperata, Phil., should therefore be regarded as a distinct, well-characterized species. Römer's Dos. prostrata L. is certainly not Spengler's (Chemnitz's) species of that name; the latter Römer has determined as Dos. Bruyiiieri, Gray. Dosinia dilecta, A. Ad. (PI. V, Figs. 11— 13|. Dosinia dilecta, A. Adams, Proc. Zool. Soc. London, 1855, p. 224, No. 15. — — — RÖMER, Monogr. d. Molluskengatt. Dosinia, 1862, p. 66, No. 77. The sound of Koh Chang, 5 fathoms, soft clay (I'/a). Long. 40 mm., alt. 41 mm., crass. 21 mm. ' The figure on PI. 29, Fig. 298 is not good, and does not agree with the description; the phrase "testa orbicular! valde compressa et complanata" suits the figure but badly; so also tlie synonyms given by Chemnitz unquestionably do not all refer to this form; liow far on the whole Linné and Chemnitz have had the same form before them I am not prepared to saj-, - Spengler and Chemnitz were in daily communication with each other; see Malakozool. Blätter, XVU, 1870, p. 99. D. K. D. VIdensk. Selsk. Ski-.. 7. Ra-kke, natuiviilensk. og mathem. Afd. V. :i. 32 250 154 Distribution: — Malacca (Dr. Traill), Pulo Bidang, N. of Penang (Skeat, Brit. Mus.). On the label of the specimens of D. dilecta, A. Ad., in the British Museum, D. striatissima, Sowerby, is given as a synonym ; I very much doubt whether this is correct, as Sowerby in "Thesaurus Conchyliorum" (p. 673) refers his species to "Sect. 6: Edge of the dorsal area raised above the circumscribing line," a feature which is not to be found at all in D. dilecta, A. Ad. Dosinia cretacea, Reeve. Arlemis cretacea, Reeve, Conchol. icon., VI, 1850, Artemis, Sp. 35. — — — SowiiRBY, Thesaur. Conchyl., II, p. 667, No. 46, pi. 142, fig. 51. Dosinia — — Römer, Monogr. d. Moll. Dosinia, 1862, p. 34, No. 32, pi. 6, fig. 8. — — — L. MoRi.ET, Journ. de Concliyl., vol. 37, p. 169. — — — Hidalgo, Obras malacologicas, I, torn. II, 1903, p. 3(19, No. 4U2. "lies du golfe de Siam" (L. Morlet). Distribution: — Persian Gulf (v. Martens), Red Sea (P. Fischer, ^ Sturany^). — Annam, Philippines. The Danish Expedition to Siam brought home no specimens of this species. Dosinia Hanleyana, H. & A. Ad. Dosinia simplex, A. Adams, Proc. Zool. Soc. London, 185r>, p. 224, No. 14 (non Artemis simplex, Hanley, Proc. Zool. Soc, 1845, p. 11). — — — Römer, Monogr. d. Gatt. Dosinia, 1862, p. 75, No. 90. — Hanleyana, H. &A. Adams, The Genera of recent Mollusca, II, 1858, p. 431. — Singaporensis, — MS., British Museum. The strand ofT the Mangrove at the station on Koh Chang (1). Long. 85 mm., alt. 8 mm., crass. 4 mm. Distribution: — Singapore (Cuming). By comparisons in the British Museum I have convinced myself that the small specimen from the Gulf of Siam corresponds with Adams's species Singa- porensis; Mr. Edg. Smith kindly tells me that that species is identical with simplex, A. Ad., a name which H. and A. Adams afterwards altered to Hanleyana, owing to its having previously been used by Hanley. Dosinia contusa, Reeve. Artemis contusa. Reeve, Conchol. icon., VI, 1850, Artemis, Sp. 38. — — — Sowerby, Thesaur. Conchyl., II, p. 672, No. 62, pi. 143, fig. 70. Dosinia — — Römer, Monogr. d. Moll. Dosinia, p. 57, No. 65, pi. 11, fig. 2. — — — L. Morlet, Jouin. de ConchjI., vol. 37, p. 170, No. 67. — — — J. Brazier, Proc. Linn. Soc. N.S.Wales, vol. 9, 1884, p. 801, No. 36. ' Catalogue d. Moll, de I'Indo-Chine, p. 231. '' Nachrichtsblatt d. Deutschen Malakozool. Gesellsch., 1905, 138. 155 251 "Iles du golfe de Siam" (L. iMüui.ktI. Distribution: — New Guinea, North and North-west Australia. This species does not occur among the material brought home by the Danish Expedition to Siam, and Dautzenberg and Fischer think' that probably it is Dosinia Gruneri, Phil., which Morlet records from the Islands in the Gulf of Siam under the name of U. contusa. Reeve. Dosinia pubescens, Phil. Cylherea {Artemis) pubescens, Philipim, .\l)bild. a. 15eschieil). neuer od. wenig gekannt. Conchyl., Ill, 1847 (1851), p. 24 (36), pi. 8, fig. 3. Artemis puljescens, Phimppi, Süwerby, Thesaurus Conchyl., II, p. 672, No. 64, pi. 143, fig. 72. Dosinia — — Römer, Monogr. d. Moll. Dosinia, p. 7!l, No. 96, pi. 15, fig. 1. Koh Kahdal, 1 — 5 fathoms, sand (1). North of Koh Kahdat, 4—5 fathoms, coarse sand ('j). Koh Mak, sandy coast ('-■). West of Koh Kut, 30 fathoms, sand and mud ('/ä). Long. 5 — ^20 mm. Distribution: — Bombay, Mekran Coast, Aden, Madagascar, Durban. — Philippines, Labuan (N. Borneo), New Holland. All the specimens from the Gulf of Siam are young, and the lamellæ which limit the convex area are therefore not so well-developed as in older individuals. In one of the specimens from Koh Kahdat the apices are red and the umbones are ornamented with reddish-brown zig-zag lines and spots. Melvill and Abeh- crombie- say also "Young specimens are nearly circular, silky in appearance and often tinged with pink." Edg. Smith'' unites with this species the following: — D. scfibriuscula, Reeve (? of Philippi), D. ovalis, Römer, D. eiinice, A. Adams, and D.bisecta, Reeve (?) (i.e. biscocta, Reeve), the last species is recorded from Japan. Cyclina elegans, H. Ad. (PI. V, Figs. 14-15). Liicina elegans, H.Adams, Proc. Zool. Soc. London, 1870, p. 791. Gulf of Rayong, 7 — 10 fathoms, sand, mud, shells (2). Long. 7 mm., alt. 7 mm., crass. 5 mm. Distribution: — Red Sea (M' Andrew). By examining H. Adams's original specimens in the British Museum I have convinced myself that my specimens from the Gulf of Siam are identical with Lucina elegans, H.Adams.' It is, however, incorrect when Adams refers that species to the genus Lucina, it being a Cyclina; as his diagnosis is deficient and also par- tially misleading, I give here a description and figures of my individuals:— Valves ' Journal de Conchyliologie, vol.54, 1906, p. 216. - Memoirs and Proceed, of the Manchester Lit. and Phil. Soc , 4 .Ser., vol. 7, p. 45. ' Proc. Zool. Soc. London, 1891, p. 421. * Mr. Edg. A. Smith has kindly verified my determination. 32- 252 156 circular, convex, white, rather thin; umbones high and situated at the middle of the axis of the shell. Apex turning towards the anterior end. The whole surface covered with a network of close-set, fine, parallel lines, which cross each other; they proceed from the umbones and from the upper sides and radiate outwards towards both ends and towards the ventral side. Upon each valve there is a large, elongated, crescent-formed lunule, circumscribed by a groove; it is glossy, destitute of network sculpture, and striped only by the lines of growth; the brown ligament is external. The interior of the valves is glossy, milky white; in the right valve there are two diverging cardinal teeth of which the posterior is bifid; in the left valve there are three cardinal teeth of which the central and largest is bifid. The margin is smooth. The sinus is high and widely triangular. Note. Clementia papyracea, Gray, has been taken at Singapore in shallow water (by Sv. Gad). Venerupis Irus L. Donax Irus, Linné, Syst. Nat., ed. XII, 1767, p. 1128, No. 111. Venenipis Irus, Linné, L. Pfeiffer in Martini u. Chemnitz, Conchyl. Cabin., XI Ud , 1 Abth., 1869, p. 245, pi. 31, figs. 17-19. — irus, — BucguoY, Dautzenberc, et Doli.fus, Moll. mar. de Roussillon, II. p. 438, pi. 67, figs. 9 — 18. — macropbylla, Deshayes, Catal. of the Concliifeia in tlie coll. of the British Museum, I, 1853, p. 193. — Proc. Zool. Soc. London, 1853, Moll. pi. XVIII, fig. 8. — — — SowERBY, Thesaur. Conchyl., II, p. 763, No. 2, pi. 165, fig. 20. — — — SowERBY in Reeve, Concliol. icon., XIX, Venerupis, Sp. 23. Rupellaria — — Pagenstecher, lieber d. v. Kossmann am Rothen Meere ges. Moll. 1877, p. 42, No. 35. — — — Rochebrune, Mater, pour la faune de l'Archipel du Cap Vert. Nouv. Arch, du Muséum, 2 Sér., Mémoires, IV, p. 255, No. 34. Venerupis — — A.H.Cooke, Ann. and Mag. Nat. Hist., 1886, p. 103. Irus — -, — Mei-vii.l and Standen, Journ. of Conchol., IX, p. 84. Venerupis — — Hidalgo, Fauna malacol. de I. Isl. Filipin., II, p. 321, No. 417. — derelicta, — Proc. Zool. Soc. London, 1853, p. 4, No. 17. — — — Sowerby. Thesaur. Conchyl., II, p. 765, No. 9, pi. 164, fig. 16. — — — — in Reeve. Conchol. icon., XIX, Vencrupis, Sp. 8. — — — Hidalgo, Fauna raalacol. de I. Isl. Filipin., II, p. 320, No. 415. — fimhriata, Sowerby, Thesaur. Conchyl., II, 1855, p. 766, No. 12, pi. 165, fig. 23. — — — in Reeve, Conchol. icon., XIX, Venerupis, Sp. 25. attenuata, — Reeve, Conchol. icon., XIX, Venerupis, Sp. 7. Koh Mesan, 15 fathoms, stones (%). Between Koh Mesan and Cape Liant, 5—9 fathoms, sand ('/a). Coast of Lem Ngob, low tide, stones {■'h). North end of Koh Chang, 1 fathom, coral blocks (1). Koh Chang, 1—2 fathoms, old coral blocks (6). Koh Kahdat {Va). Long. 1 — 14 mm. Distribution: — Singapore (shallow water, Sv. Gad), Madras, Bombay, Persian Gulf, Karachi, Aden, Red Sea, Suez, Mediterranean, Black Sea, Atlantic Ocean (the coast of Europe from England and Ireland to Cape Vert), Mauritius. — Annam (V. attenuata, Sow.), Philippines, Japan, Aru Isl. {V. attenuata, Sow.), Funafuti Atoll. 157 253 It is iiol possible for me to distinguish between specimens from the Gulf of Siam and European individuals, e. g. from the Mediterranean. Besides the synonyms above enumerated several more can undoubtedly be added, thus, e. g. V. semi- purpurea, Dunk.,' mitis, Desh. , '^ planicosta, Desh., etc."' Fam. Petricolidae. Naranio lapicida, Chemn. Venus Lapicida, Chemnitz, Concliyl. Cabin., X, 1788, p. 356, pi. 172, figs. 1664—65. — - - Gmelin, Syst. Nat., ed. XIII, p. 32(i!l, No. 148. Naranio lapicida, — Deshayk.s, Catalogue of the Concliifera in the coll. of the Brit. Mus., I, 1853, p. 216, No. 2. Petricola ~ — Sowerby, Thesaur. Conchyl., 11, 1855, p. 776, No. 20, pi. 166, fig. 26. ~ — — Krebs, West-Ind. mar. shells, 1864, p. 108. — — — Sowerby in Reeve, Couchol. icon., XIX, Petricola, Sp. 24. — — — EuG. Smith in Zoolog. Collect, of H. M. S. Alert, 1884, p. 98, No. 22. Choristodon lapicidum, Chemnitz, Phitchaiu) and Gatliff, Proceed. Roy. Soc. Victoria, vol. 16, 1903, p. 121. Venus divaricata, Chemnitz, Conchyl. Cabin., X, 1788, p. 357, pi. 172, figs. 1666—67. Petricola - d'Orbigny, Mollusques de I'ile de Cuba, II, 1853, p. 265, No. 463. Naranio — Chemnitz, Deshayes, Catal. Conchif. Brit. Mus., I, 1853, p. 216, No. 1. Petricola — — Sowerby, Thesaur. Conchyl., II, p. 776, No. 19, pi. 166, figs. 24— 25. — — Deshayes, Mabille et Le Mesi.e, Journ. de Conchyl., vol. 14, 1866, p. 117. — — Chemnitz, v. Martens in v. d. Decken's Reisen in Ost-Afrika, 111, 1869, p. 66, pi. 3, fig. 3. — — — Sowerby in Reeve, Conchol. icon., XIX, Petricola, Sp. 22. Choristodon divaricatum, Chemnitz, H. & A. Adams, Genera of rec. Moll., II, 1858, p. 442, pl. 110, fig. 2. Venus divergens, Gmelin, Syst. Nat., ed. XIII, 1790, p. 3269, No. 147. Petricola coslata, Lamarck, Systeme d. anim. s. vert., 1802, p. 121. Naranio — — Gray, Ann. and Mag. Nat. Hist., 1853, XI, p. 38. Petricola lucinalis, — Hist. nat. d. anim. s. vert., V, 1818, p. 504, No. 4. — éd. 2, VI, p. 157, No. 4. Koh Chang, 1 fathom, old coral blocks (12). Koh Kahdat, 1 fathom, sand (1). Long. 7—23 mm. Distribution: - Gulf of Manaar, Maldive Archip., Persian Gulf, Gulf of Oman, Aden, Red Sea, Mauritius, Zanzibar, Mozambique, Querimba Isis. — Poulo Condor, Aru Isl., Torres Strait, Mast Head Reef (Queensland), St. Vincent's Gulf (South Australia), Victoria, Yap, Pelew Isis., Funafuti Atoll. — East coast of America: Florida, Greater and Lesser Antilles (to Martinique, Dall). Fam. Cardiidae. Cardium (Acanthocardium) setosum, Redf. Cardium setosum, Redfield, Ann. Lyceum Nat. Hist. New York, IV, (18461 1848, p. 168, pl. XI, fig. 1. — — — Edg. Smith, Rep. Challenger Lamellibranchiata, 1885, p. 158. ■ Dunker, Index moll. mar. Japon., p. 2Ü8. - Pilsbry, Catal. of the Mar. Moll, of Japan, 1895, p. 129. - Taken at Botany Bay (Angas) and Tasmania (Tate & May). ^ That V. Irus may also occur ornamented with vivid colours has been stated by Dautzenbekg (loc. cit. p. 443) and Pallary (Journ. de Conchyl., 1900, pp. 403-4); it then recalls V. exotica, Hani. 254 158 Cardiiim setosiim, Ri;i)i-iei,i), Hidalgo, Obras malacologicas, I, tom. II, lildS, p. ;t29, No. 4'J8. — latum. Chemnitz, Conch)!. Cabin., VI, 1782, p. 197, pi. 19, figs. 192-93. — — Autorum (Reuve, Römkh e. a. non Boün fide F. Bh.ueh' et Edg. A. Smith; loc.cit.l. Islands in the Gulf of Siam (L. Morlet, Journ. de Conchyliologie, vol. 37, 1889, p. 168). The Danish Expedition to Siam collected no specimens of this species. Distribution: — Mergui Isis., Nicobars, Madras, Ceylon, Bombay, Persian Gulf, Gulf of Aden. — Hong Kong, Philippines, Java, Sulu Isis. Cardium (Acanthocardium) Sueziense, Iss. Carditim Sitezicnsix, I.s.sel, Malaco!, d. Mar Rosso, 18(i9, p. 7(1, pi. 3, fig. 4. — sueziense — Edg. Smith, Lamellibianciiiata of the Challenger Exped., p. 158, pi. VIII, figs. 2— 2 b. — fragiim, Linné var. sueziense, Issel, Ch. Hedley, Australian Museum, Sydney. Memoir 111, 1896 - 1900, p. 504. Between Koh Mesan and Cape Liant, 5 9 fathoms, sand (2). Between Koh Riol and Koh Mesan, 3—5 fathoms, sand (12). Koh Kahdat, 1 fathom, sand (2). West of Koh Kut, 15 fathoms, mud (15). Long. 4—10 mm. Distribution: — Ceylon, Gulf of Manaar, Angrias Bank, Laccadive and Maldive Archip., Persian Gulf, Mekran Coast, Red Sea (Stubany), Gulf of Suez (common, IssEL and M' Andrew). — Torres Strait, Levuka, Vili Isis., 12 fathoms (Challenger), Funafuti (Ellice Isis.). Edg. a. Smith (loc. cit. p. 159) is quite right in thinking that the present species may become larger than his specimens (7 mm.) from the Viti Islands; in the Gulf of Siam thej' attain, as stated above, 10 mm. Issel gives as the maximum for the specimens from the Gulf of Suez 0 mm., Sturany^ mentions the following measure- ments for specimens from Massaua : — alt. 725 mm., long. 75 mm., crass. 575 mm. Several of the individuals from tlie Gulf of Siam were ornamented with distinct intercostal sculpture, and both entirely white individuals and also forms with red dots and spots occur; in the latter the red colour is also seen upon the white interior of the valves. Valves are often found which are vivid yellow upon the interior of the umbonal region. Ch. Hedley (loc. cit.) is of opinion that the species under consideration is a variety of Hemicardinm fragum L. Upon the basis of the material collected at Funafuti Atoll (Ellice Isis.) he says: "The four dozen odd valves before me exhibit much variation in contour, and they a|)pear to pass by gradual transition into tyi)ical C. fragrum" but I doubt whether he is right in this supposition. (I do not understand the reason why Hedley always in his paper gives "C. fragrum L." for C. fragum L.). • F. Brauer, Sitzungsber. d. k. k. Akad. d. Wiss. Wien. Matheniat. naturw. Classe, Bd. 77, 1 Abth., p. 127. - Nachrichtsblatt d. Deutseh. Malakozool. Gesellsch., 1905, p. 139. 159 255 Cardium (Bucardium) Asiaticuni, Brug. Cardiiim Asiaticiim, Bhuciière, Eiicyelop. method. Vers, Totn. I, 17i(2, p. 224, No. 19, pi. 293, lig. 2. — — — Reeve, Conchol. icon., 11, Cardium, Sp. yo. — — — Martini u. Chemnitz, Coiichyl. Cabin., X, 2 Abth., p. (i(i, pi. 2, ligs. 4 — .'). — — — BÜLOW, Nachrichtsbl. d. Deutsch. Malakozool. Gesellsch., 1905, p. 81, pi. 2, fig. 7. — lima, Si'iiNGi.ER, Schröter, Einleit. in d. Conchylienkeniitn., 111, 178(i, p. 53. — — Gmelin, Systeraa Naturae, ed. XIII, p. 3253, No. 31). — lamellatiim, Spengler, Skrivter af Naturhistorie Selskabet, V, 1799, p. 8. North ot Koh Kam, 5 fathoms, gravel. Koh Chuen, 30 fathoms. Long. 30—46 mm. Distribution: — Nicobar Isis., Ceylon arid Madras, South Africa (Natal, Port Elisabeth). — China. Dunker ' undoubtedly erroneously records Guinea as the locality for the present species. Spengler's original specimens in the Zoological Museum of the University of Copenhagen are labelled "Card, lamellatiim Spengl., Niquebar." Cardium (Bucardium) coronatum, Spengl. Cardium coionalum, Spkngler, ,1. S. Schröter, Einleit. in d. Conchylienkenntniss, 1786, 111, p. 53, pi. Vll (in II Bd. , fig. 13 a, b. — — — Skrivter af Naturliistorie-Selskabet, 1799, V, p. 9, pi. 1, fig. 1. — — — Römer in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 2 Abth., p. 08, pi. 12, figs. 3-5. — — — BÜLOW, Nachrichtsbl. d. deutsch. Malakozool. Gesellsch., 1905, p. 81, pi. 2, fig. 6. — — — Daiitzenberg et Fischer, Journ. de Conchyl., vol. 54, 1906, p. 214. — fimbriatum, Woou, General Conehology, 1835, p, 235, pi. 56, ligs. 4— 5. — — — Reeve, Concliol. icon., II, Cardium, Sp. 91. — — P. Fischer, Catal. d. Moll, de llndo-Chiiie, p. 229. Commonly distributed from Koh Chang to Koh Samit, 3—30 fathoms, clay, mud and sand. Long. 4—39 mm. Pavie in 1884 took it at the islands in the Gulf of Siam (Journ. de Conchyl., vol. 37, p. 168). Distribution: — Mergui Archip. (v. Martens), Bay ofBengal (Madras, Aracan coast), from Goa to Bombay, Karachi. — Annam (Crosse, Fischer, Boutan), China (Hong Kong). Spengler's original specimens in the Zoological Museum of the University of Copenhagen are labelled "aus Niquebar." Melvill and Standen (Proc. Zool. Soc. London, 1906, p. 838) write: "After detailed examination of many examples in all stages of growth, it is the opinion of Mr. Alexander Abercrombie that coronatum Spengler is synonymous (with Cardium Asiaticum, Chemn.);" at present I cannot agree with this opinion. ' Index molluscor. quae in itinere ad Guineam infer, coll. G. Tams, 1853, p. 50, No. 134. 256 160 Cardium (Bucardium) multispinosum, Sow. Cardium multispinosum, G. li Sowerby, Proc. Zool. Soc. London, 1840, p. 106. — — — Concliol. Illustrations, figs. 38— 38 a. — — — Rkeve, Concliol. icon., II, Cardium, Sp. 10. — — — Martini u. Chemnitz, Conchyl. Cabin., X Bd., 2 Abtli., p. 67, pl. 12, figs. 1-2. — — — BiiLow, Nachrichtsbl. d. Deutsch. Malakozool. Gesellsch., 1905, p. 81, pi. 2, fig. .'■>. Taken in different localities between Koh Chang and Koh Kut, 6—20 fathoms, mud and clay (5). Long. 21 — 41 mm. Distribution: — Mozambique (v. Martens). — Philippines (Cuming, Hidalgo), China (J. Reeves), north and east coasts of Australia (Angas, "Challenger"-Exped., "Alerf'-Exped.). Cardium (Bucardium) Sinense, Sow. Cardium Sinense. G. B. Sowerby, Proc. Zool. Soc. London, 1840, p. 10,^. — — — Conchol. Illustrations, fig. 35. — — — Reeve, Conchol. icon., II, Cardium, Sp. 3. — — — RÖMER in Martini u. Chemnitz, Conchyl. Cabin., X Bd., 2 Abth., p. 73, pl. 12, figs. 11-12. — — — P. Fischer, Catalogue d. Mollusques de I'lndo-Chine, p. 229. — — — Dautzenberg et Fischer, Journ. de Conchyl., vol. 54, 1906, p. 214. Commonly distributed from Koh Chuen to Koh Kong in 3—30 fathoms, mud, clay and shells. Long. 1 — 40 mm. Distribution: — Annam (Crosse et Fischer, Boutan), Hong Kong, China (Sowerby), Philippines (Sowerby, Hidalgo), Java (Reeve). The number of the ribs varies greatly; G. B. Sowerby states 23, Römer 21 - 23, and Reeve 24. In my collection there are three specimens from "China" with 25 ribs, but all the specimens from the Gulf of Siam have 21 — 22 ribs. Cardium (Trachycardium) flavum L. Cardium flavum, Linné, Systema Naturae, ed. X, p. 680, No. 71. — ed. XII, p. 1123, No. 87. — — — Martini u. Chemnitz, Concliyl. Cabin., X, 2 Abth., p. 56, pl. 7, figs. 7-8; pl. 5, fig. 10. — magnum, Chemnitz, Conchyl. Cabin., VI, p. 196, pl. 19, fig. 191. — pectiniforme, Born, Test. Mus. Caesar. Vindob., 1780, p. 49, pl. Ill, fig. 10. — — — P. Fischer, Catalogue d. Moll, de I'Indo Chine, 1891, p. 230. — rugosum, Lamarck, Hist. nat. d. anim. s. vert, VI, p. 400, No. 23. — — — Reeve, Conchol. icon., II, Cardium, pi. XIV, No. 68. — Dupuchense, (Reeve), Morlet. Journ. de Conchyl., vol. 37, 1889, p. 168. — — — P. Fischer, Catalogue d. Moll, de I'Indo Chine, 1891, p. 229. Koh Mak, dead specimens on the coast. Koh Kahdat, 1 — 5 fathoms, sand, stones (1). North end of Koh Chang, 1 — 2 fathoms, old coral blocks, several dead specimens. Coast of Koh Kahdat (^l-i). 161 257LjlLIBRAi»1 \^\ ^.^ Long. 8 — 35 mm. Pavie in 1884 took it at the islands in the Gulf of Siam (Morlet, Journ. de Conchyl., vol. 37, p. 168). Distrihut ion : — "Bangkok" (Dautzenberg), ' Bay of Bengal, Ceylon, Arabian Sea, Persian Gulf, Gulf of Aden, Red Sea, Suez Canal, Madagascar and Rodriguez, Mozambique and Zanzibar, Natal (Sowerby), Malay Archip. (the most commonly occurring species, v. Martens), Philippines, north and east coasts of Australia. Card. Diipuchense, Reeve, is recorded to have been taken at the "Island of Dupuch, Torres Straits (found on the reefs at low water); Dring, H. M. S. Beagle." Melvill & Standen" do not record it from Torres Strait, but C. rugosum, Lam. is recorded from "Boydong Cays." Ed. Römer ' regards, and undoubtedly correctly, C. Dupiichense, Reeve, as a variety of C. flavum. Cardium (Trachycardium) impolitum, Sow. Cardium impolitum, G. B. Sowerby, Proc. Zool. Soc. London, 1840, p. 107. — — — Conchol. Illustr., Sp. 49, figs. 6 and 66. — — — Reeve, Conchol. icon., II, Cardium, Sp. 80. — — — Martini u. Chemnitz, Conchj'l. Cabin.. X, 'i Abth., p. 62, pi. XI, fig. 12. Koh Chuen, 30 fathoms (1). Between Koh Kut and Koh Kahdat, 10 fathoms, shells {'I2). Between Koh Mesan and Cape Liant, 5 — 9 fathoms (^/a). Long. 10 mm., alt. 12 mm. (long. 27 mm., alt. 33 mm.). Distribution:— Karachi (Melvii.l & Standen). — China (Sowerby), Tahiti (Frauenfeld). Cardium (Trachycardium) arenicolà, Reeve. Cardium arenicolum, Reeve, Conchol. icon., II, 1843, Cardium, Sp. 78. — arenicola, — Lischke, Japanische Meeres Conchyl., II, p. 125. — maculosum, Sowerby, Conchol. Illustr., Sp. 48, fig. 63 (non Wood). Koh Kram 20—30 fathoms (2 + '12). Around Koh Mesan and Koh Chuen, 5 — 38 fathoms, stones and shells (8). Koh Kahdat, 1 — 2 fathoms ('2). Long. 3 mm., alt. 35 mm. (long. 32 mm., alt. 38 mm.). Distribution: — Red Sea (Sturany). — Philippines (Cuming), Nagasaki (Lischke). The specimens from the Gulf of Siam have about 52 — 55 ribs, and as Reeve for his species states only 46 ribs, I thought, at first, that the specimens were per- haps Card, transcendens, Melvill & Standen, ' in which species there are 58 ribs. But J. Cosmo Melvill, to whom I sent a few specimens, kindly tells me that the}' ' According to a written communication from Ph. Dautzenberg these specimens must most properly be referred to C. Dupuchense = pectiniforme , Born. The locality "Bangkok" is certainly due to a mistake. - Journ. Linnean Soc. Zool., vol. XXVII, p. 191. ^ Martini u. Chemnitz, Conchyl. Cabin., Cardiacea, p. 58. * Journal of the Linnean Soc, Zoology, vol. 27, 1899, p. 199, pi. 11, fig. 21. D. K. D. Vidensk. Sclsk. Skr , 7. Hække, naturvidensk. ou math Afd V. 3. 33 258 162 exactly agree with specimens of Card, arenicola, Reeve, from Ticao (Philippines) in his collection. Lischke's five specimens from Nagasaki have also only 46 — 47 ribs. Cardium (Papyridea) rugatum, Gron. CartUum niyatum, Gronovius, Zoophylacium Groiiovianuni, 1781, fasc. Ill, p. 266, No. 1125, pi. 18, fig. 5. — - — Martini u. Chemnitz, Conchyl. Cabin., X Bd., 2 Abth., p. 77, pi. 3, figs. 1—3. — — — Reeve, Conchol. icon., II, Cardium, Sp. 63. — apertum, Chemnitz, Conchyl. Cabin., 1782, VI, p. 189, pi. 18, figs. 181-83. North of Koh Kam, 5 fathoms, gravel (2). Long. 35—40 mm. Distribution:— Singapore, Mergui Archip. (v. Martens), Gulf of Manaar (Thurston). — Philippines (Cuming, and others), Hong Kong (Frauenfeld), Gulf of Yedo (Lischke), Java and Flores (Dunker), Amboina (Tapparone Canefri), New Britain (v. Martens). Ed. v. Martens ' thinks that Solen bullaius L. is undoubtedly synonymous with the present species. Cardium (Papyridea) papyraceum, Chemn. Cardium papyraceum, Chemnitz, Conchyl. Cabin., VI, 1782, p. 190, pi. 18, fig. 184. — — — Reeve, Conchol. icon., II, Cardium, Sp. 9. — — — Martini u. Chemnitz, Conchyl. Cabin., X Bd., 2 Abth., p. 78, pi. 3, fig. 4 ; pi. 12, figs. 19-20. Papyridea papyracea, — Hidalgo, Obias malacologicas, 1, tom. II, 1903, p. 344, No. 444. Cardium muticum, Reeve, Conchol. icon., II, Cardium, Sp. 32. Koh Kahdat, 1 fathom, sand ('/2). Long. 28 mm. Distribution: — Singapore (Sv. Gad), Ceylon, Gulf of Manaar, Karachi, Mekran Coast, Persian Gulf, Gulf of Tadjourah (Gravier), Suez Canal (Bavay), Mauritius, Natal. — Philippines, Japan (northwards to Hakodate), Blitong (post-tertiary), north and east coasts of Australia. Cardium (Papyridea) Annae, Pilsbry. Cardium annœ, Pilsbry, Proc. Acad. Nat. Sc. Philadelphia, vol. 56, 1904, p. 557, pi. 40, fig. 20. From Cape Liant to Koh Kut, common, 1 — 30 fathoms, sand, mud, gravel, and shells. Long. 3 — 11 mm. Distribution: — Japan (Pilsrry). Among the individuals from the Gulf of Siam there are several in which the valves are almost quite white excepting the umbones which are purple in colour. ' Ruinphius Gedenkboek, 1902. Mollusken, p. 127 (19). 163 259 Cardium (Papyridea) Hungerfordi, Sowb. Cardiiim {Papyridia) hungerfordi, Sowerby, Journal of Malacology, vol. VIII, IflOl, p. 103, pi. IX, fig. 5. — hungerfordi, Sowerby, Pil.sbry, Proc. Acad. Nat. Sc. Philadelphia, vol. .')G, 1904, p. ,')55, pi. 41, fig. 17. Commonly distributed at Koh Chang, Koh Kut, Koh Kahdat and Koh Bidang, 3 — 30 fathoms, soft clay, sand and mud. Largest specimen: Long. 95 mm. Distribution: — Japan (Sowerby, Pilsbry). This species may easily be confounded ^vith the young of Card, coronatum, Spgl., from ^vhich it is, however, distinguished by a stronger gloss, the absence of ribs at the middle, and by its often being ornamented with two reddish-brown tints at the middle on each side of the umbones (young specimens of C. coronatum have often reddish-brown wavy lines transversely across the valves), the valves are more tumid, and the posterior side somewhat prolonged in a rostrum-like manner. Pilsbry, however (loc. cit. p. 556), describes two varieties of C. Hunger- fordi, to which some of these characters cannot be applied. Cardium (Laevicardium) Australe, Sow. Cardiiim Australe, Sowehby, Proc. Zool. Soc. London, VIII, 1840, p. 105. — Conchol. Uliistr., part 48, Cardium, figs. 12— 12* (1834). — australe. — Martini u. Chemnitz, Conchyl. Cabin., X, 2 Abth., p. 70, pi. 12, figs. 8—9. — — — Reeve, Conchol. icon., II, Cardium, Sp. 97. — IBucardium) australe, Sowerby, Edg. Smith, Rep. on the Lamellibranchiata of the Challenger Exped., p. 160. — {Laevicardium) — — Edg. Smith, Moll, of the Maldive and Laccadive Archipelagoes, 1903, II, pi. II. p. 625, No. 343. — pulchrum, Reeve, Conchol. icon., II, 1845, Cardium, Sp. 98. — (Papyridea • pulchrum. Reeve, Ed. v. Martens, Mollusken d. Maskarenen u. Seychellen, 1880, p. 148. — — — — Edg. Smith, Rep. Zool. Collect. Voyage "Alert, ■ 1884, p. 507, No. 11. West, of Koh Chang, 20 fathoms, mud (2). Long. 11 — 12 mm. Distribution:— Salang, Mergui Isis., Andamans, Ceylon, Gulf of Manaar, Maldive Archip., Gulf of Oman, Aden, Red Sea, Seychelles, Amirantes, Mascarenes, Zanzibar, Cape of Good Hope (Jay). — Poulo Condor, Philippines, China Sea, "Coasts of Australia," Lifu, Viti Isis , Samoa Isis. As neither Sowerby nor Edg. Smith mention Card. Australe, Sow., in their lists of the Mollusca of South Africa I think that Jay's record of the occurrence of the species at the "Cape of Good Hope" should be regarded as open to doubt. It is a mistake when Edg. Smith in his report on the Lamellibranchiata of the Challenger Expedition writes regarding this species that "it is not apparently adorned with an epidermis, judging from the series of specimens which I have examined," because already in 1878, in the "Proc. Zool. Soc. London," p. 819, he had written concerning this same species "The Andaman examples are rather young and bear the remains 33* 260 164 of their epidermis, which takes the form of very thin, short, irregular yellowish lamellæ arising from the radiating striæ." In the specimens from the Gulf of Siam this epidermis is found especially upon the front and hinder sides of the valves; in addition, there is present especially upon the posterior end, slight remnants of epidermis between the radiating ribs. Melvill and Standen '■ consider C. tenui- costatum, Lam. to be a variety of C. Australe, Sow. Cardium (Laevicardium) lobulatum, Desh. (PI. V, Figs. 16-19). Cardium lobulatum, Deshayes, Proc. Zool. Soc. London, XXII, 1854, p. 332, No. 08. At Koh Kahdat, 1-10 fathoms, sand and mud (14). South of Koh Mak, 5 6 fathoms (2). Long. 23 mm., alt. 26 mm. Distribution: — Mnldive Archip. — Philippines. I owe thanks to Mr. Edg. Smith for the determination of the present species. Hemicardium (Lunulicardia) retusum L. Cardium retnsum, Linné, Systema Naturae, ed. XII, 1767, p. 1121, No. 75. — ~ Martini u. Chemnitz, Conchyl. Cabin., X, 2 Abth., p. 118, pi. VI, figs. 1 — 4. — — Linné, Reeve, Concliol. icon., II, Cardium, Sp. 103. — subretusum, Sowerby, Reeve, Conchol. icon., II, Cardium, Sp. 100. Several (23) specimens taken between Cape Liant and Koh Kut, 1—15 fathoms, sand, gravel and mud. The specimens are all small, the largest specimen is 23 mm. broad. Distribution: — Bay of Bengal, India (Madras), Ceylon, Gulf of Manaar, Bed Sea, Suez Canal ("rare" M' Andrew, Cooke), Seychelles, Béunion, Zanzibar. — Philippines, Torres Strait. The records of the different authors concerning the distribution of this species to China (v. Martens, Beeve, and others) and Japan (Dunker, and on his authority Pilsbry) are open to doubt, neither Lischke (Japan. Meeres Conchylien) nor P. Fischer (Catalogue d. Moll, de ITndo Chine) mention this species from these regions. Hemicardium (Fragum) unedo L. Cardium unedo, Linné, Syst. Nat., ed. X, 1758, p. 680, No. 68. — — — Mus. Ludovicæ Ulricæ reg., 1764, p. 488, No. 40. — — — Reeve, Conchol. icon., II, Cardium, Sp. 13. — — — Martini u. Chemnitz, Conchyl. Cabin., X, 2 Abth., p. 101, pi. 4, figs. 11-12. Hemicardia unedo, Linné, L. Morlet. Journ. de Conchyl., voL 37, 1889, p. 168, No. 58. At Koh Kahdat, 1—5 fathoms, sand (14). Islands in the Gulf of Siam (Morlet). Long. 6—8 mm. ' Proc. Zool. Soc. London, 1906, p. 837. 165 261 Distribution:— Singapore, Mergui A rchip., Nicobars, Madras, Ceylon, Mauritius. — Poulo Condor, Cochin China, Philippines, Moluccas, Java, Malay Archip., New Guinea, Torres Str., Port Molle (Queensland), West Australia, Lifu Isl., Salomon Isis., Viti Isis. The Danish Expedition obtained only quite small specimens of this species from the Gulf of Siam. Mr. Ph. Dautzknberg writes to me that his Hemicard. tegulatum ' must be regarded as a variety of Hemicard. unedo L. Hemicardium (Fragum) fragum L. Pl.V, Fig. 20). Cardiiim fragum. Linné, Syst. Nat., ed. X, 1758, p. 679, No. (i7. — ed. XII, p. 1123, No. 83. — — — Mus. Ludov. Ulricæ reg., p. 488, No. 39. — — — Reeve, Conchol. icon., II, Cardium, Sp. 23. — — — Martini u. Chemnitz. Conchyl. Cabin., X, 2 Abtli.. p. 1U5, pi. 4, figs. 9 — 10. Between Koh Kahdat and Koh Kut, 6 fathoms, clay mixed with sand ('2). Koh Kahdat at the strand, numerous specimens. Koh Mak, sandy coast ('/s). Long. 4—10 mm. Distribution:— Andamans, Nicobars, Gulf of Tadjourah, Mauritius, east coast of Africa, Querimba Isis. — China Sea, Philippines, Amboina, Java, Borneo, Sulu Isis., Liukiu Isis., Torres Strait, Port Curtis and Mast Head Reef (Queensland), New Zealand, New Caledonia, Gilbert Isis., Funafuti (EUice Isis.), Paumotu Isis. The specimens which have been obtained are all very small. According to O. FiNSCH this species is used as food in the Gilbert Islands. Several specimens of a peculiar variety (var. carjna/a m.), with a decidedly prominent keel extending from the umbo down towards the hinder angle of the ventral side, produced by the strong" development of the two ribs at that place, have been taken on the strand of Koh Kahdat and at Koh Chang; this variety is figured on Pl.V, Fig. 20. Hemicardium (Fragum) carditaeforme, Reeve. (Pl.V, Figs. 21-22). Cardium Carditœforme, Reeve, Conchol. icon., II, Cardium, Sp. 127. Between Koh Mesan and Koh Chuen, 15 — 38 fathoms, stones with shells (7). Koh Chuen, 10 — 15 fathoms (1). Between Koh Mesan and Cape Liant, 5 — 9 fathoms, sand CI2). Strand of Koh Kahdat ('/:;). West of Koh Kong, 10—15 fathoms (1). Long. 4—9 mm. Distribution:— Andamans, Gulf of Suez ("rare" M'Andrew, Cooke). As the figure by Reeve is not good, I give a new figure of the species. Hemicardium (Ctenocardium) fornicatum, Sow. Cardium fornicatum, Sowerby, Proc. Zool. Soc. London, 1840, p. 110. — — — Conchol. Illustr., Sp. 84, fig. 50. — — — Reeve, Concliol. icon., II, Cardium, Sp. 110. ' Journal de Conchyliologie, vol. 48, 1900, p. 5. 262 166 Hemicardittm (Ctenocardium) fornicatum, Sowerby, Melvim. & Standen, Proc. Zool. Soc. London, 1906, p. 840. Cardium Adamsii, Reeve, Voyage of "Samarang," p. 77, pi. 22, fig. 2. — Virgo, Reeve, Concho), icon., 1845, II, Cardium, Sp. 120. Commonly distributed from the Gulf of Rayong and Cape Liant to Koh Kut, 1—15 fathoms, sand, mud, and gravel (26). Long. 6—26 mm. Distribution: — Andamans (Edg. Smith), S. Nilandu and N. Male Atoll (Edg. Smith), Persian Gulf (Melvill & Standen), Red Sea (Sturany), Providence Isl., Mascarenes ("Alert"). — Borneo ("Samarang"), Tizard Bank, southern China Sea (Edg. Smith), Tonga Isis. ("Challenger"). The present species is often difficult to distinguish from Hemicardium imbri- catum, Sow. The number of the ribs is variable; the intercostal sculpture (at any rate in the material before me) is the same in both the species. Sowerby says regarding fornicalam that the ribs are set with "vaulted imbrications," while Edg. Smith ' states regarding the same species that they are ornamented with "short hollow spines." In younger and well-preserved specimens these "spines" may be as well-developed as in imbricatum. The specimens from the Gulf of Siam are quite white on the outer side of the valves and precisely resemble Card, virgo, Reeve, which is synonymous with C. fornicatum, Sow. Hemicardium (Ctenocardium) imbricatum, Sow. Cardium imbricatum, Sowerby, Proc. Zool. Soc. London, 1840, p. 110. — — — Conchol. Illustr., Sp. 85, fig. 48. — — — Reeve, Conchol. icon., II, Cardium, Sp. 28. Several (22) specimens taken at Koh Chang, Koh Mak, Koh Kahdat, Koh Kut, Koh Samit and several places in 5—30 fathoms, mud, gravel, and clay mixed with sand. Long. 6 — 27 mm. Distribution:— Torres Strait (Murray Isl.), off Cape York (North AustraHa), West Australia (Swan River). Card, hystrix, Reeve, from the Philippines and the Andamans, with strongly developed spines, approaches somewhat Card, imbricatum, Sow. Fam. Tridacnidae. Tridacna squamosa, Lam. Tridacna squamosa, Lamarck, Hist. nat. d. anim. s. vert., VI, 1 p. 1819, p. 106. — éd. 2, VII, 1836, p. 10. — - — QuoY et Gaimard, Voyage de l'Astrolabe, H, 1833, p. 487, pi. 79, fig. 1. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 4 Abth., p. 5, pi. 1, figs. 1—3; pi. 2, figs. 1—2. ' Report on the Lamellibranchiata of the Challenger Expedition, p. 164. 167 263 Tridacna sqiiumosa, Lamarck, Reeve, Conchol. icon., XIV, Tridacna, Sp. 3. — — — SowERBY, Thesaurus Conchy!., V, 1887, p. 180, pi. 485-489*, figs. 2, 7, 15, 17. — — — L. MoRLET, Journ. de Conchyl., vol. 37, 1889, p. 168. — — — P. Fischer, Catal. de Moll. de I'Indo Chine, p. 228. — — — Hidalgo, Obras nialacolôgicas, I, tom. Il, 1903, p. 386, No. 489. — gigas L. var. squamosa, Lamarck, Cli. Hedley, Australian Museum, Sydney, Memoir III, 1896 — 1900, p. 504. Koh Kahdat, 1 — 2 fathoms, coral (1). Islands in the Gulf of Siani (Morlet). Long. 245 mm. Distribution: — Singapore, Mergui Isis., Nicobars, Ceylon, Seychelles. — Poulo Condor, Annam, Philippines, Loo Choo Isis., Japan, Moluccas, Sulu Isis., Java, Timor, New Guinea, Torres Strait, North and East Australia, New Caledonia, South Sea Islands ("What information we have, suggests that the range of this species is almost co-extensive with that of the reef-building corals." Ch. Hkdley loc. cit.). Edg. Smith says ^ "I should not be surprised if Tridacna squamosa or Tridacna rudis should prove to be the early stages of this colossal form {Tridacna gigas)." A. H. Cooke- and Ch. Hedley' have arrived at a similar conclusion; Hedley thinks that "No characters of permanent value separate T. squamosa from T. gigas." Tridacna crocea, Lam. Tridacna crocea, Lamarck, Hist. nat. d. anim. s. vert., VI, 1 p. 1819, p. 106. — éd. 2. VII, 1836, p. 10. — — — QuOY & Gaimahd, Voyage de l'Astrolabe, II, 1833, p. 488, pi. 79, figs. 2 3. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 4 Abth., p. 6, pi. 1, fig. 6. — — — Reeve, Conchol. icon., XIV, Tridacna, Sp. 9 (incl. varr. Sp. 7 and 8). — — - SowERBY, Tliesaurus Conchyl., V, 1887, p. 181, pi. 486-87, figs. 5— 6, 8-10. North end of Koh Chang, 1 fathom, boring in old coral blocks (2). Koh Kahdat, in coral blocks (1). Long. 115 mm., alt. 84 mm. Distribution: — Singapore, Mergui Isis., Andamans, Nicobars, Persian Gulf, Aden, Madagascar. — Philippines, Loo Choo Isis., Moluccas, Cape York (N. Australia), Lifu, New Ireland, Rarotonga. Fam. Chamidae. Chama multisquamosa, Reeve. Chaîna multisquamosa. Reeve, Conchol. icon., IV, 1846, Chama, Sp. 12. — — - Martini u. Chemnitz, Conchyl. Cabin., VIII, 5 Abth , p. 33, pi. 14, figs. 1—2. Many specimens taken in 23 different localities between Koh Rin and Koh Kut, 1 — 30 fathoms, sand, shells, clay and mud. ' Lamellibranchiata of the Challenger Expedition, p. 171. - Annals & Magaz. Nat. Hist, Ser. 5, vol. 18, p. 97. ' ^ Australian Museum, Sydney, Memoir III, 1896 — 1900, pp. 504 — 5. 264 168 Largest specimen: Long. 31 mm., alt. 26 mm. Distribution: — Singapore (low water, Sv. Gad), Poulo Condor, Philippines. It is very disheartening to look through the literature of the species of the genus Chama, and of their distribution, because of the uncertainty and casuality which prevail in it ; this is of course for the greater part due to the bad diagnoses and figures in which the characteristic marks of distinction, e. g. in the sculpture, are disregarded, and instead are given long descriptions of insignificant and usually individual details pertaining to colour and outline; but certainly authors are often too careless in determining solitary specimens without having a large quantity of material at their disposal for comparison — better no determination than an erroneous one. It is very characteristic when Ed. v. Martens' says "Die Arten dieser Gattung sind sehr schwer gegeneinander abzugrenzen, daher ihre Bestimmung und Benennung oft etwas willkürlich," and A. H. Cooke ; '-' "It would be impossible here to enter into a discussion of the facts in the case of a genus notoriously so variable as Chama, when Reeve has made fifty-five species out of material prob- ably better represented by ten." Chama fragum, Reeve. Chama fragum, Reeve, Conchol. icon., IV, 1847, Chama, Sp. 48. — — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 4 Abtli., p. 22, pi. 10, figs. 2-3. — — — Crosse & Fischer, Journ. de Concliyl., vol. XL, 18Ü2, p. 76. Koh Kram, 30 fathoms (Vi). S. of Koh Chuen, 30 fathoms, shells (2). Koh Chang, at low tide (1). North end of Koh Chang, 1 fathom, old coral blocks (2). The sound between the stations, 3— 5 fathoms, soft clay (1). Coast of Lem Ngob C/s). West coast of Cambodge in the Gulf of Siam (Pavie). Long. 27 mm., alt. 31 mm. Distribution:— Persian Gulf (Melvill & Standen), Aden (Shopland), Red Sea (Sturany). — Philippines, Hong Kong, Spencer's Gulf, South Australia? (Angas), Samoa and Cook's Isis.'? (Mus. Godeffroy). Chama granulata, Clessin, ' is probably nothing else but the present species. Chama cristella. Lam. Chama cristella, Lamarck, Hist. nat. d. aniin. s. vert., VI, 1819, p. 96. — éd. 2, 1835, VI, p. 585. — — — Reeve, Conchol. icon,, IV, 1847, Chama, Sp. 42. — Reeveana, Clessin, Martini u. Chemnitz, Conchj'I. Cabin., VIIl, 4 Abth., p. 38, pi. 16, figs. 3 — 4. Between Koh Mesan and Koh Chuen, 15 fathoms, stones (2). S. of Koh Chuen, 30 fathoms, shells (1). Long. 21 mm., alt. 28 mm. Distribution:— Mergui Archip., Moluccas (Clessin). — Java, Celebes, Spencer's Gulf? (South Australia, Angas). ' Die Mollusken d. Maskarenen u. Seychellen, 1880, p. 147. , - Annals and Magaz. of Nat. Hist., Ser. 5, vol. 18, p. 96. ' Martini u. Chemnitz, Conchyl. Cabin., loc. cit., p. 4U, pi. 17, fig. 4. 169 265 Clessin, in his deficient Monograph of the genus Chama fin Martini u. Chem- nitz's Conchyl. Cabin.), states that the species, described by Reeve under the name of Ch. cristella, ditîcrs from Lamarck's species, as Lamarck's diagnosis does not at all agree with Reeve's form; therefore Clessin gives Reeve's species a new name (Reeveana, Clessin) and applies Lamarck's name to a West Indian species which does not at all agree with Lamarck's diagnosis. The whole of this change is un- necessary and incorrect; Reeve's and Lamarck's forms are undoubtedly identical; besides Reeve expressly says: "the example here figured has been satisfactorily identified with Lamarck's original specimen in the collection of M. Delessert." Chatna pulchella, Reeve. Chama pulchella. Reeve, Conchol. icon., IV, 1846, Chama, Sp. 10. — — - Report Zoolog. Collect. Voyage "Alert," 1884, p. 102, No. 35. Koh Mak, sandy coast (Va). Long. 35 mm., alt. 30 mm. Distribution: — Torres Strait (Melvill & Standen), Port Molle, Queens- land (Coppinger), Cape Upstart, New Holland (Jukes). The exterior of the somewhat worn shell collected at Koh Mak is of a pretty pink colour. Note. A small, solitary valve, which somewhat recalls Chama cornuta, Chem- nitz, has been taken at Koh Tulu. Chama cornuta, Chemnitz (var), Conchyl. Cabin., VII, 1784, pp.150 and 154, pi. 5'i, fig. 518. — — — Der Naturforscher, XX, 1784, p. 13, pi. 1, fig. 3. Lamarck' was correct in doubting whether Chemnitz's Ch. cornuta was identical with his Ch. florida from St. Domingo (therefore in the list of synonyms belonging to that species he has queried the citation). Clessin,- however, in his Monograph of Chama has, as a matter of course, put Chemnitz's species as a synonym of C. florida, Lam., which is entirely wrong. Chemnitz's original specimen, which has been at my disposal, is from the Nicobars, and is a young individual which, because it has not been attached to any other object, has developed its umbones into a pair of twisted horns ; as it is somewhat worn, it is not easy to form any definite opinion regarding this species. Fam. Myidae. Corbula (Aloidis) crassa, Hinds. Corbula crassa, Hinds, Proc. Zool. Soc. London, XI. 1843, p. 55. — — — Zoology of the voyage of H. M. S. "Sulphur." Mollusca, p. 67, pi. 20, figs. 1- — — — Reeve, Conchol. icon., II, Corbula, Sp. 8. — — — Hanley, Catal. of recent biv. shells, p. 344, pi 12, fig. 29. — — — var., Edg. Smith, Lamellibranchiata of the Challenger Exped., p. 30. ' Hist. nat. d. anim. s. vert., 2 éd., VI, p. 583. '^ Martini u. Chemnitz, Conchyl. Cabin., VIII, 5 Abth., p. 12. D K. I). Vidensk. Selsk. Ski-., 7. H.iîkke, naturvidensk. og mathem. Aid. V. .■!. 34 266 170 E. of Cape Liant, 9 fathoms, shells (5). Gulf of Rayong, 7 — 10 fathoms, sand and mud (2). S. of Koh Saniit, 14—20 fathoms, mud (6). S. of Koh Tulu, 10 fathoms, mud (2). W. of Koh Chang, 20 fathoms, mud (Ws). N. of Koh Kahdat, 4—5 fathoms, coarse sand (1). Koh Kahdat, 1 — 5 fathoms, sand (1). Between Koh Kahdat and Koh Kut, 6 — 10 fathoms, mud mixed with sand (■''/2). Koh Mak, sandy coast (^/s). S. of Koh Mak, 5—6 fathoms (2). W. of Koh Kong, 10—15 fathoms (1). Long. 8 — 24 mm. Distribution: — Singapore, Strait of Malacca, Mergui Archip., Andamans, off Port Blair, Andaman Isls., 100 fathoms (Edg. Smith), Gulf of Manaar. — Poulo Condor, Philippines, Formosa, Strait of Macassar, New Guinea, Torres Str., Mast Head Reef (Queensland), Port Essinglon, Dampier'sLand (NW. Australia), NE. Australia. The specimens, for the most part, are thick-valved and vary greatly in form, but quite thin-valved specimens also occur; thus, for example (from Singapore) a left valve of the following dimensions:- long. 19 mm., alt. 7 mm., crass. 4 mm.; it is very thin-valved, and without a trace of the denticulation upon the dorsal and ventral margins characteristic of the species; it greatly resembles Edg. Smith's species C. Macgillivrayi, and like the latter it has a shallow depression down the middle (which C. crassa also very frequently has); the hinge characters are also less pronounced than in the thick-valved specimens of C. crassa of the same size, from which it appears to differ greatly, but it is, in reality, only an unthickened individual. Corbula (Aloidis) tunicata, Hinds. Corbula tunicata, Hinds, Proc. Zool. Soc. London, 1843, p. 5.5. — — — Reeve, Conchol. icon., II, Corbula, Sp. 5. — — — Zoology of the voyage of "Sulphur," Mollusca, p. fiS, No. 281, pi. 20, figs. 4 — .'5. — — — Edg. Smith, Lamellibianchiata of the Challenger Exped.. p. 29. — — — Pritchard and Gatliff, Proc. Roj'. Soc. Victoria, vol. 16, 190;^, p. 101. — scaphoides, — Proc. Zool. Soc. London, 1843, p. 5(). — — — Reeve, Conchol. icon., 11, Corbula, Sp. 24. — — — Edg. Smith, Lamellibranchiata of the Challenger Exped., p. 32, pi. 7, fig. 3. — — — Pritchard and Gatliff, Proc. Roy. Soc. Victoria, vol. 16, 1903, p. 101, NW. of Koh si Chang, 10 fathoms, mud (1). Gulf of Rayong, 7—10 fathoms, mud ('/ä). Sound of Koh Chang, 5 fathoms, soft clay ('/a). West coast of Koh Chang, 10 fathoms, mud (V2). S. of Koh Bidang, 9 fathoms, mud (1). S. of Koh Mak, 5 — 6 fathoms (4). Between Koh Kahdat and Koh Kut, 6-10 fathoms, mud mixed with sand ("/a). N. of Koh Kut, 10 fathoms, mud (-/a). W. of Koh Kut, 15 fathoms, mud (3). Long. 7 — 25 mm. (long. 25 mm., alt. 17 mm., crass. 14 mm.). Distribution: — {t. = tunicata, Hinds; s. = scaplwides, Hinds). Singapore (s.), Mergui Archip. (t.), Ceylon (s.), Cape of Good Hope (/.). — Philippines (/. s.), China Sea (t.), Hong Kong Harbour (s.), Amboina (/.), Strait of Macassar (f.), Arafura Sea (/. ), Torres Strait (t.s.), Cape York (s.). Port Jackson, Sydney (t. s.), Mast Head Reef, Queensland (s.), Port Molle, Queensland (/. s.), Victoria (/. s.). Port Darwin, NW. Australia (/.), Tasmania (s.). 171 267 I cannot find sufficient reason for separating the two forms funicala and scaphoides as distinct species, the differences are entirely individual. Among the rather large quantity of material which I have at my disposal, are several transitional forms. The vivid coloration which Hinds has given in his figure of tiinicata in the report of the "Sulphur" Mollusca, was not found by me in any of the indi- viduals I have had for examination. Corbula (Aloidis) erythrodon, Lam. Corbula erythrodon, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 49(j. No. 3. ~ éd. 2, VI. p. 138, No. 3. — — — Reeve, Conchol. icon., II, Corbula, Sp. 4. — — — LiscHKE, Japan. Meeres-Conchj'l., I, p. 136. E. of Cape Liant, 9 fathoms, shells (Vs). N. of Koh Kam, 5 fathoms, gravel (2). Between Koh Riot and Koh Mesan, 3—5 fathoms, sand (1). Between Koh Mesan and Cape Liant, 9 fathoms (1). Koh Kalidat, 1 — 5 fathoms, sand (2 -|- *;2). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (Vs). Long. 7 — 20 mm. Distribution: — Poulo Condor, China, Japan, New Zealand. Corbula pallida, Hinds (recorded from Singapore and the Nicobars), is certainly synonymous with the present species. Corbula lineata n. sp. (PI. V, Figs. 23—24). This species is oblong-triangular in form, somewhat inequivalve (the right valve being somewhat larger than the left), moderately convex, the valves thick and solid, and whitish in colour with slight indication of pale red. The umbo is situated at about the middle, often nearer to the front end. The apices of the umbones are placed close together and they curve over towards the front. From the umbo a sharp keel extends over each valve down towards the posterior ex- tremity, which is prolonged in a rostrum-like manner. The dorsal margin slopes gradually down towards the front end, from whence it is continued in a curve down to the straight ventral margin. Towards the pointed posterior end the dorsal margin slopes in a straight line. In both valves, when the animal has reached a certain size, the ventral margins turn back and grow inwards towards each other. The portion of the posterior end which is bounded by the two keels forms an oval; towards the central line (the opening between the valves) of this oval there occurs on each side a smaller keel, by which another oblong oval is formed. The surface of the valves is covered with close-set, concentric, raised thread-like lines, the interstices between which are finely striped transversely with close-set radiating lines. The interior of the valves is white, the muscle impressions and the palliai line are yellow; a narrow depression extends from the umbonal region down towards the ventral margin. The solitary cardinal tooth in the right valve is large, strong and curved upwards; it fits into a corresponding pit in the left valve, behind which there is a large denticle supporting the ligament. 34* 268 172 Long. 85 mm., alt. 5 mm., crass. 45 mm. Between Koh Mesan and Cape Liant, 9 fathoms (3). The present species, which somewhat resembles the West Indian species Corb. Kjaeriana, C. B. Adams,' is very characteristic and can easily be distinguished by its form and beautiful sculpture. Corbula subquadrata, Melvill. Corbula subquadrata, Melvill, Proc. Zool. Soc. London, 1906, p. 843, pi. 56, fig. 7. Koh Chuen, 30 fathoms (1). Coast of Lem Ngob, low tide, stones (9). Koh Chang, low tide ('/a). North of Koh Kut, 10 fathoms, mud ('/a). Long. 25— 6 mm. (long. 5 mm., alt. 35 mm., crass. 25 mm.). Distribution: — Bombay, Persian Gulf, Gulf of Oman. This species varies greatly both in regard to outline and convexity, several of the specimens from the Gulf of Siam agree exactly with Melvill's figure, while others differ in outline and are oblong (long. 6 mm., alt. 4 mm., crass. 3'5 mm.); but the peculiar hanging rostrum and the strong sculpture are found in all the individuals. Melvill, in his diagnosis, does not mention that the concentric folds upon the whole surface and also the interstices between them, seen under magnifica- tion, are transversely closely striped; this ornamentation is very characteristic, and occurs in all my specimens. In full-grown specimens there are usually more than "about 12 concentric ribs" (as stated by Melvill), and although in the umbonal region their prominence is extremely slight, yet often at least fourteen fully deve- loped folds may be counted. Corbula arcaeformis n. sp. (PI. V, Figs. 25—26). The shell is oblong, very convex, clear-white, thin and dully pellucid; it is twice as long as it is high, rounded at the anterior end and drawn out into a point at the posterior end. From the beak a keel extends to the point of the posterior end; the space thereby formed between the dorsal side and the keel, is divided into two halves by a groove which originates at the beak. The middle portion of the shell, especially towards the ventral side, is depressed, and this makes the ventral margin concave. The surface is covered with fine, irregular lines of growth, which towards the ventral side are coarser; these are most pronounced upon the space mentioned above limited by the keel. Under magnification may be seen in the shell-substance a great many fine, white lines, which radiate from the umbones down towards the ventral margin; in quite young individuals and in the umbonal region of well-preserved, older specimens, these lines may be seen as small, fine, irregular, slightly raised stripes. The beaks are situated in the front third of the ' Dall, Report on the Mollusca coll. by the Steamer "Blake," I, 1886, p. 316, pi. I, fig. 6. The American couchologists erroneously name this species C. Kjoeriana. 173 269 shell and curve over towards the front. In the right valve there is one cardinal tooth, which fits into a corresponding pit in the left valve, behind which is a stout process or denticle supporting the ligament. The interior of the valves, like the exterior, is clear-white in colour. Long. 95 mm., alt. 5 mm., crass. 55 mm. Between Koh Kut and Koh Kahdat, 10 fathoms, shells (^/a). Koh Kahdat ("a). South of Koh Kahdat, 8—10 fathoms, mud (^/a). This small characteristic species, which in form recalls an /Irca (ßarfca/ia), stands nearest Corbula tenuis. Sow., from which it differs, however, in many points. The specimens which I have before me are not well-preserved, no trace of epidermis is seen upon any of them ; also, I cannot, unfortunately, state anj'thing about the reciprocal size of the two valves. But in all probability, the difference in size is not very great, as both right and left valves are at hand, but of different individuals. Corbula rugifera, A. Ad. (Smith). Corbula rugifera, A. Adams, MS. in Coll. Cuming. Brit. Mus. — — — Edg. Smith, Proc. Malacolog. Soc. London, V, isms, p. 399, No. 373, pi. 15, figs. 9—10. — — H.Adams, Melvill and Standen, Proc. Zool. Soc. London, 1906, p. 843. Koh Kram, 20 fathoms (-/a). Long. 35 — 8 mm. Distribution: — Singapore (Sv. Gad, Zoolog. Mus. Copenhagen). Karachi (Hindustan, Melvill). Umkomaas (South Africa, Burnup). After Edg. Smith in 1903 had published the description of the present charac- teristic species from South Africa, Melvill, in 1906, recorded that it had been taken at Karachi. Its occurrence at Singapore and in the Gulf of Siam, renders it probable that later on it may also be found in the interjacent waters. Corbula Taheitensis, Lam. Corbula taïtensis, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 496, No. 5. — Taïtensis, — — — — éd. 2, VI, p. 139, No. 5. — Taheitensis, — Reeve, Conchol. icon., 11, Corbula, Sp. 15. — Taliitensis, — Hanley, Catal. of rec. biv. shells, p. 46, pi. 12, fig. 30. — Taitensis, — Hidalgo, Fauna malacol. de 1. isl. Filip., II, 1903, p. 31, No. 59. Koh Chuen, 30 fathoms ('/a). Between Koh Mesan and Koh Chuen, 25—38 fathoms, stones and shells (1 -|- ^/a). North end of Koh Chang, 12 fathoms, old coral blocks ('/a). Long. 6—8 mm. Distribution— Aden. — Philippines, New Guinea, Torres Str., Tahiti, Funafuti Atoll (Hedley). 270 174 Corbula sulcata, Lam. Corhnla sulcata, Lamahck, Systeme d. anim. s. vert., 1801, p. 137. — Hist. nat. d. aniiii. s. vert., V, 1818, p. 495, No. 2. — éd. 2, VI, p. 138, No. 2. — — — Encyclop. method. Hist. nat. d. vers, II, 2, 1830, p. 8, No. 1. — Tableau encycl. et méth. Moll, test., pi. 230, fig. 1. — — — Hanley, Catal. of rec. bivalve shells, p. 45, pi. 13, fig. 48. — — — Reeve, Conchol. icon., II, Corbula, Sp. 2. NW. of Koh si Chang, 10 fathoms, mud (1). North of Koh Kut, 10 fathoms, mud (»*'/2). W. of Koh Kut, 10-15 fathoms, mud (1 + ^2/3). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (i^/s). Koh Kahdat ('/s). Long. 5 — 14 mm. (alt. 125 mm., long. 14 mm.). Distribution:— Lamarck records: l'Océan indien? Hanley and Reeve: Senegal. Rochebrune: Porto-Praya (Rang). Corbiila fortisnlcata. Smith, is very closely allied to the present species. In the British Museum there is a specimen labelled "Corbiila fortisnlcata, Smith var." from "Jack's Island, South Sea," which agrees completely with some of the specimens from the Gulf of Siam, and these cannot possibly be separated from C. sulcata, as there are evenly transitional forms between them and the typical C. sulcata. Lam. Corbula monilis, Hinds. (PI. V, Figs. 27-30). Corbula monilis, Hinds, Proe. Zool. Soc. London, XI, 1843, p. 58. — — — Reeve, Conchol. icon., II, Corbula, Sp. 35. — — — Edg. Smith, Laraellibranchiata of the Challenger Expedit., p. 34. — — — HiDAi.GO, Fauna malacol. de 1. isl. Filipinas, II, p. 33, No. 64. Many specimens taken in 19 different localities between Koh Kram and Koh Kut, 1 —30 fathoms, sand, mud and shells. Long. 1'5 — 3 mm. Distribution: — Singapore (2 — 3 fathoms, coral reef, Sv. Gad). — Philippines, Torres Strait, Mast Head Reef (Queensland), Corbula solidula, Hinds. (PL V, Figs.31-34 and 42-44!. Corbula solidula, Hinds, Proe. Zool. Soc. London, XI, 1843, p. 58. — — — Reeve, Conchol. icon., II, Corbula, Sp. 41. — - - Mollusca of the voyage of H. M. S. "Sulphur," 1845, p. (ii). No. 288. — — — Hidalgo, Fauna malacol. de 1. isl. Filipinas, II, 1903, p. 34, No. 66. — ebnrnea, — Proe. Zool. Soc. London, XI, 1843, p. 58. — — — Reeve, Conchol. icon.. II, Corbula, Sp. 42. — — — Mollusca of the voyage of H. M. S. "Sulphur," 1845, p. (i'J, No. 2!I0, pi. 20, fig. 14. — — — Hidalgo, Fauna malacol. de 1. isl. Filipinas, II, 1903, p. 34, No. 07. Many specimens taken in 26 different localities between Koh si Chang and Koh Kut, 1—30 fathoms, mud, sand, shells and clay. Long. 2 — 45 mm. 175 271 Distribution: — Philippines, Strait of Macassar, New Guinea. Hinds says regarding eburnea "This shell closely approaches C. solidula, but is distinguished by its somewhat more triangular shape, polished, ivory-like, flattened valves, and the slightly sulcate sculpture." All these characters are however not constant; among the large quantity of material at my disposal, in which both forms occur, there are evenly transitional forms between the polished, almost smooth eburnea, ornamented with only a few slight transverse ribs towards the ventral margin, and the strongly ribbed, thick-valved solidula. The outline varies some- what, the colour is clear-white in almost all the specimens from the Gulf of Siam. Cuming's specimens of eburnea from the Philippines are of a yellowish colour, but otherwise agree entirely with my individuals from the Gulf of Siam. Corbula (?) mirabilis n. sp. (PI. V, Figs. 35—37). The shell is squarish-oblong in form, flat, thin-valved and white. The umbones are situated towards the posterior end. The prodissoconch is clear, smooth and glossy. Anteriorly the upper margin is straight and passes bj' a gentle arch into the front margin, which forms a semi-circle. The ventral margin is straight, and parallel with the upper margin. The posterior margin passes in an almost straight line obliquely down from the umbo; a rugged keel extends right across the posterior part of the shell from the umbo down to the point at which the ventral and the posterior margins meet. The surface is rough and the lines of growth are coarse and irregular. The interior of the valves is somewhat glossy and the roughness of the surface can here be seen owing to the thinness of the valves. In the hinge there is anteriorly a crater-like depression (probably for the reception of a tooth in the left valve). The margins of this depression have, at the back, a small, pointed tooth and at the front a larger tooth which is continued anteriorly into a long lamella immediately under the upper margin of the valve; beside and somewhat in front of the larger tooth mentioned there are, in addition, upon the upper margin, two tooth-like nodules which project beyond the margin and are visible outside of the shell. Behind the circumscribed depression named is a triangular excision al- most immediately under the apex; upon the upper edge of the thickened posterior margin there is a shallow groove in which, no doubt, the ligament is placed; this groove is limited above by a tooth-like process upon the upper margin which, upon the surface of the shell, resembles a small ear. The front muscle-impression is distinctly visible, but the palliai line only partially; the palliai sinus appears to be wanting. Long. 11 mm., alt. 55 mm., crass, (test, dextr.) 1 mm. North of Koh Kut, 10 fathoms, mud ('/s). The above diagnosis is based upon the solitary (probably right) valve obtained, and I refer the specimen, but with great doubt, to the genus Corbula. In spite ol 272 176 the dental peculiarities, I am of opinion that it ought most properly to be placed under the family Corbnlidae. It will be of interest, when complete specimens are at hand, to ascertain accurately the systematic place of this characteristic form. Sphenia quadrangularis n. sp. (PI. V, Figs. 38—41). This shell is squarish-oblong in form, flat, white, very thin, hyaline, and glossy. The unibones, which are not very prominent, are situated at about the middle, slightly towards the posterior end. The protoconch is circumscribed as a small, clear, smooth vesicle. The upper side rounds evenly into the anterior end which is continued in a curve to the ventral side which is quite straight. From the umbo a sharp keel extends over the shell down to the posterior part of the ventral side ; the ventral margin meets, almost at a right angle, the posterior margin which ascends steeply towards the upper side into which it passes with rounded outline. The surface is rough and the lines of growth are coarse, especially upon the flat middle part of the shell where the surface towards the ventral side has numerous grooves and stripes. The interior of the valves is glossy, and owing to their thinness the roughness of the surface also occurs on the interior. In the left valve there is a pointed, somewhat triangular cardinal tooth, which is situated in front of and below the apex; this tooth fits into a pit in the hinge-plate of the right valve; this hinge-plate is situated in the front of the apex and there also occurs upon it, in front of the above-mentioned pit, a small nodule, like a rudimentary tooth. The front part of the upper margin in the right valve rises along a short distance, so that it protrudes somewhat above the margin of the left valve. The ligament is internal, the impressions of the ad- ductor muscles, the palliai line, and the palliai sinus cannot be seen. Long. 10 mm., alt. 5 mm., crass. 3 mm. The coast of Koh Kahdat (1). I refer this highly characteristic species with some doubt to the genus Sphenia; when a larger quantity of material is at hand (unfortunately only a single dead specimen has been obtained) its place will be ascertained with greater certainty. When Edg. Smith ' writes regarding Sphenia perversa, Blanford, that: — "Mr. Blanford makes a curious mistake with regard to the hinge. He says, "In every respect, ex- cept the position of the lamellar tooth in the hinge of the left valve instead of the right, the shell appears to be a true Sphenia." In Mr. Blanford's figure the "lamellar tooth" is properly depicted in the left valve; in specimens of this species in the British Museum it is also in the left, and in every other species and specimen examined by the writer it is in the same valve," — the reason for this must undoubtedly be sought in the fact that Blanford'-^ has seen, in several text-books (e. g. by ' Annals and Mag. of Natural History, vol. XII, 6 Ser., 1893, p. 279. ■ Journ. of tlie Asiatic Soc. of Bengal, vol. 30, II, 18G7, p. 08. 177 273 H. & A. Adams, ' Tryon, - P.Fischer,' and others), the erroneous statement that the characteristic cardinal tooth occurs in the right valve, while, in reality (as correctly stated by Turton, ' Forbes & Hanley, "' Edg. Smith, " and others), it is found in the left valve. Sphenia perversa, Blanf. Sphenia perversa, Bi.anpord, Journ. of the Asiatic Society of Bengal, vol. 36, p. 11, 1867, p. 68, pi. 3, figs. 4 — 6. — — — Edg. Smith, Annals and Magaz. Nat. Hist., vol. 12, 6 Ser., 1893, p. 279, No. 6, pi. 15 A, fig. 6. Between Koh Mesan and Koh Chuen, 25 — 38 fathoms, stones and shells (1). Koh Chuen, 10 — 15 fathoms (1). Between Koh Mesan and Cape Liant, 5 — 9 fathoms ('/s). Coast of Lem Ngob, low tide (4). Koh Chang, low tide (1). North end of Koh Chang, 1 — 12 fathoms, old coral blocks (12). Gulf at the south end of Koh Chang (6). North of Koh Kahdat, 4 — 5 fathoms, coarse sand (1). Koh Kahdat, 1 — 2 fathoms, corals (1). Long 2 — 11 mm. Distribution:— Delta of the Irawady, Pegu. Like all Mollusca that live in holes and tunnels, which they themselves have made or which were made in other ways, S. perversa, Blanf., varies greatly in form according to the locality which it inhabits; I think it will scarcely be possible to maintain Edg. Smith's species S. inaequalis from Singapore; I have specimens of S. perversa Blanf., before me with Hat left valves and which otherwise almost com- pletely agree with Smith's figure and description of S. inaequalis, but the flat left valve is certainly an individual character only. Cryptomya elliptica, A. Ad. Sphænia elliptica, A. Adams, Proc. Zool. Soc. London, XVUl, 1850, p. 88. Cryptoimiu - — Annals & Mag. Nat. Hist., 1868, p. 366. — — — Angas, Proc. Zool. Soc. London, 1871, p. 99. — — — Dunker, Index moll. mar. Japonici, 1882, p. 178, pi. 7, figs. 17— 19. — truncata, Gould, Otia Conchol., p. 163. Koh Kahdat (Va). S. of Koh Kahdat, 8—10 fathoms, mud (Va). N. of Koh Kut, 10 fathoms, mud (2 + V2). W. of Koh Kul, 15 fathoms, mud ('72). Long. 4—12-5 mm. Distribution. — Japan, Sydney. 1 The Genera of recent Mollusca, 11, 1858, p. 357. '■' Structural and systematic Conchology, III, 1884, p. 140. 3 Manuel de Conchyliologie, 1887, p. 1122. * Conchylia insul. Britannicarum, 1822, p. 36. ^ A history of British Mollusca, I, 1853, p. 192. '' loc. cit. p. 279. D. K n. Vlilensk Selsk. SUr.. 7. Rakke, nnlurvidciisU. oi; niiilhem. Afd. V. 3. 35 274 178 Farn. Solenidae. Solen grandis, Dunk. Sulen (/randis, DuNKEn, Proc. Zool. Soc. London, 1861, p. 418, No. 1. — — — Novitates Concliol., 11, Meeres Conchy]., p. 71, No. 77, pi. 24, fig. 5. — — — LiscHKE, Japanische Meeres-Conchyl., I, 1869, p. 141. — — — SowERBY in Reeve, Conchol. icon., vol. XIX, Solen, Sp. 5. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 18, No. 20, pl. 7, fig. 1. — — — E. V. Martens, Süss- u. Biackwasser-Moll. d. hid. Archipels, p. 274. Off Koh Kam, 10 fathoms, gravel (Vs). Long. Ö6 mm. Distribution: — Philippines, China, Japan. S. Ceylonensis, Leach (= S. intermedins, Koch = S. trnncalus, Wood (Sow.)), S. cartas, Desm. (= S. abbreviatus, Phil. = S. brevis, Reeve), and S. regalaris, Dunk., come exceedingly near S. grandis, Dunk. Solen corneus, Lam. Sulen corneus, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 451, No. 2. — éd. 2, VI, p. 54, No. 2. — — — Delesskrt, Recueil de coquilles décr. p. Lamarck, 1841, pl. 2, fig. 2. — — — Philippi, Abbild, neuer od. wen. gek. Conchyl., III, p. 44, No. 3, pl, 2, fig. 2. — — — SowERBY in Reeve, Conchol. icon., XIX, Solen, Sp. 19 (non pl. 7, fig. 18 b). — • — — Dunker, Index moll. mar. .lapon., 1882, p. 173. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI lid., 3 Abth., p. 9, pl. 2, figs. 8-9. — — — E. v. Martens, Süss- u. Brackwasser-Moll. d. Ind. Archip., p. 276, No. 5. — — — Hidalgo, Fauna mal. de 1. isl. Filipinas, II, 1903, p. 16, No. 32. — — — Edg. Smith & Bloomer, Proc. Zool. Soc. London, 1906, II, p. 856. The strand off the Mangrove at the station on Koh Chang (1 + '/s). Long. 31—38 mm. Distribution: — Karachi, Gulf of Manaar, Gulf of Aden, Red Sea, Chuaka Bay (Zanzibar Island), Durban. — Philippines, Tschifu (Gulf of Petschili), Japan, Java, Borneo. This species is recorded with doubt by K. Martin ' from "the stream-tin- deposits" of Blitong (a post-tertiary formation). Solen linearis, Spengl. Solen linearis, Spengler, Skrivter af Naturhistorie- Selskabet, III, 2 H., 1794, p. 87, No. 3. — — - Chemnitz, Conchyl. Cabin., XI, 1795, p. 198, pl. 198, figs. 1931-32. — — Chemnitz, Sowehby in Reeve, Conchol. icon., XIX, Holen, Sp. 22, — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth,, p. 23, No, 29, pl. 9, fig. 4. — — Spengler, E. v. Martens, Süss- u. Brackwasser-Moll. d. Ind. Archipels, p. 277, No. 6. — — Chemnitz, Hidalgo, Fauna malacol. de I. isl. Filipinas, 19U3, 11, p. 16, No. 31. ' Notes from the Leyden Museum, III, 1881, pp. 20 and 22. 179 275 Between Koh Rin and Cliff Rock, 15 fathoms (1 + '/a). Between Koh Mesan and Cape Liant, 5—9 fathoms (%). Koh Chuen, 30 fathoms (V2). West of Koh Kut, 15 fathoms, mud (1). Long. 15 — 66 mm. Distribution:— Nicobars, Ceylon. — Philippines, Japan, Borneo, Java. Solen vaginoides, Lam. Solen vaginoides, Lamarck, Hist. nat. d. anini. s. vert., V, 1818. p. 451, No. 3. — éd. 2, VI, p. 54, No. .3. — — — Delesseht, Recueil de coquilles décr. p. Lamarck, 1841, pi. 2, fig. 3. — — — Philippi, Abbild, u. Beschreib, neuer od. wen. gekannt. Conchylien, I, p. 36, No. 3, Solen, pl. 1, fig. 3. — — — SowERBY in Reeve, Conchol. icon., XIX, Solen, Sp. 23. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 16, No. 17, pl. 7, fig. 2. — — — Pritchard and Gatliff, Proc. Roy. Soc. Victoria, vol. 16, 1903, p. 99. Between Koh Mesan and Cape Liant, 5—9 fathoms (Va). South of Koh Chuen, 30 fathoms, shells (Vs). Sound of Koh Chang, 5 fathoms, soft clay (^/->). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (Vs). West of Koh Kut, 30 fathoms, sand and mud (Va). Long. 6 — 38 mm. Distribution:— Singapore, shallow water (Sv. Gad, *;2). "Habite au canal d'Entrecastaux, et à toutes les îles de la Nouvelle Hollande" (Lamarck). South Australia, Tasmania. The specimens from the Gulf of Siam exactly agree with Philippi's figure and description. CulteUus scalprum, Gould. Solen scalprum. Gould, Proc. Boston Soc. Nat. Hist., Ill, (1849) 1850, p. 214. — Expedition Sliells, p. 74. — Unit. States E.\])lor. Exped., Mollusca, p. 388. pl. 33, fig. 502 (non Solen scalprum, King . Pharus — — Conrad, American Journ. of Conchol., Ill, Append., p. 26. CulteUus — — E. V. Martens, Suss- u. Brackwasser-Mollusken d. Ind. Archipels, 1897, p. 265, No. 2. — subellipticus. Dünker, Proc. Zool. Soc. London, 1861, p. 421, No. 15. — — — SowERBY in Reeve, Conchol. icon., vol. 19, CulteUus, Sp. 9 (non fig. 9, pl. IlL. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 43, No. 10, pl. 16, fig. 3. Siliqua subelliptica, — P. Fischer, Catalogue d. Moll, de I'lndo Chine, p. 273. Golfe de Siam (L. Morlet). The Danish Expedition to Siam collected no specimens of this species. Distribution: — Singapore, Strait of Malacca, Poulo Penang, Salang, Mergui Archip. — Java. Note. CulteUus vitreus, Dunker, was taken in 2—3 fathoms at Singapore. 35' 276 180 Cultellus (Pharella) ovalis, Dunk. Plmrella oualis, Dunker, Proc. Zool. Soc. London, 1861, p. 423, No. 24. — — — Novitates Conchologicae, MoU. mar., p. 118, No. 134, pi. 39, flg. 4. Cultellus — — SowERBY in Heeve, Conchol. icon., XIX, Cultellus, Sp. 24. Pharella — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abtli , p. 56, No. 7, pl. 10, flg. 5. — — — P. Fischer, Catalogue d. Moll, de I'Indo-Chine, p. 273. Cultellus (Pharella) ovalis, Dunker, E. v. Martens, Süss- u. Brackwasser-Moll. d. Ind. Archipels, p. 269, No. 7. Sound of Koh Chang, 3—4 fathoms, soft clay (V2). Coast of Lem Ngob ('/a). I^ong. 13 — 68 mm. "Golfe de Slam" (Morlet). Distribution: — Singapore. Dunker's and Sowerry's figures of this species differ rather considerably; my specimens correspond exactly with Sowerry's figure, which also agrees best with the diagnosis. Cultellus (Ensiculus) cultellus L. Solan Cultellus, Linné, Syst. Nat., ed. X, 1758, p. 673, No. 27. — ed. XII, p. 1114, No. 37. — Mus. Ludov. Ulricæ reg., 1764, p. 474, No. 15. — cultellus, — ' Chemnitz, Conchyl. Cabin, VI, 1782, p. 52, pl. 5, figs. 36—37. — — — Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 453, No. 8. — éd. 2. VI. 1835, p. 56, No. 8. Ensiculus cultellus, Linné, H. Adams, Proc. Zool. Soc. London, XXVIII, 1860, p. 360. Cultellus — — Sowerby in Reeve, Conchol. icon., XIX, 1874, Cultellus. Sp. 23. Ensiculus — — Dunker, Index moll. mar. Japon., 1882, p. 174. Cultellus — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 40, No. 6, pl. 3, figs. 7-8, pl. 14, fig. 2. — — — E.V.Martens, Süss- u. Brackwasser-Moll. d. Ind. Archipels, 1807, p. 270, No. 8. — — — Hidalgo, Fauna raalacol. de 1. isl. Filipinas, II, 1903, p. 23, No. 44. — cumingianus, Dunker, Proe. Zool. Soc London, 1861, p. 422, No. 19. — Cumingianus, — Sowerbv in Reeve, Conchol. icon., XIX, Cultellus, Sp. 7. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 39, No. 4, pl. 14, fig. 5. — lividus, — Proc. Zool. Soc. London, 1861, p. 423, No. 21. — — — SowERBY in Reeve, Conchol. icon., XIX, Cultellus, Sp. 1. — — — Clessin in Martini u. Chemnitz, Conchj'l. Cabin.. XI Bd., 3 Abth., p. 40, No. 5, pl. 14, fig. 4. — concinnus, Dunker, Proc. Zool. Soc. London, 1861, p. 423, No. 23. — {Ensiculusi Philippianas, Dunker, Malakozool. Blatter, 1877, p. 68, No. 4. Ensiculus Philippianus, Dunker, Index moU mar. Japon., p. 174, pl. 7, fig. 23. (Ensiculus Philippii, Dunk.). Cultellus — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 36, No. 1, pl. 4, fig. 5. £;isis asperus. Dunker in schedis. Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 45, No. 13, pl. 14, fig. 3. Off Koh Kam, 10 fathoms, gravel (1). N. of Koh Kam, 5 fathoms, gravel ('/a). Between Koh Mesan and Cape Liant, 5 — 9 fathoms (1). S. of Koh Chuen, 30 fathoms, 181 277 shells ("2). W. of Koh Chang, 20 fathoms, mud (1). S. of Koh Mak, 5-6 fathoms (1). Koh Kahdat, 1 fathom, sand and corals (3). Long. 22—56 mm. Distribution:— Singapore (Danish Exped. to Siam, 2—3 fathoms, coral reef, 2 specimens), Andamans, Tranquebar, Ceylon, Mekran Coast, Persian Gulf, Aden, Red Sea, Suez (50 m., Sturany). — Philippines, China, Japan, Amboina, Java, New Guinea, Torres Strait. Cultellus (Ensiculus) cultellus L. var. marmoratus, Dunk. Ciiltellus marmoratus, Dunker, Proc. Zool. Soc. London, 1861, p. 423, No. 22. Ensiculus — — Index raolluscor. mar. Japon., 1882, p. 174, pi. 7, fig. 24. Cultellus — — E. V. Martens, Süss- u. Brackwasser-MoU. d. Ind. Archipels, 1897, p. 271, No. 9. — — — Hidalgo, Fauna malacol. de I. isl. Filipinas, II, 1903, p. 23, No. 45. — {Ensiculus) maculatus, Preston, The Journal of Malacology, vol. XII. 1903, p. 8, pi. 2, fig. 36. N. of Koh Kahdat, 4—5 fathoms, coarse sand (1). Koh Kahdat, 1 fathom, sand and corals (2). Long. 45 —52 mm. Distribution: — Cej'lon, Red Sea, Suez. — Japan, Philippines (?). I am convinced that C. marmoratus, Dunk., can scarcely be kept distinct from the highly variable C. cultellus (even as a variety), but as the three specimens which I have before me from the Gulf of Siam precisely agree with Dunker's diagnosis and figure, I have given them as varieties. The specimens from Koh Kahdat were taken under the same conditions and in the same locality as C. cultellus; in all the three specimens from the Gulf of Siam, the valves, towards the posterior end, are compressed in the middle, so that when viewed from the gaping, posterior end, the latter has a placentiform outline. The darker colour and the concave dorsal margin are also some of the characteristics of this form. Siliqua radiata L. Solen radiatus, Linné, Syst. nat., ed. X, 1758, p. 673. No. 28. - ed. XII, p. 1114, No. 38. — Mus. Ludov. Ulricæ reg., 1764, p. 474, No. 16. — — — CHEMNrrz, Conchyl. Cabin., VI, p. 54, pi. 5, figs. 38—39. Cultellus — — Sowerbv in Reeve, Conchol. icon., XIX, Cultellus, Sp. 13. Machaera radiata, Linné, Chenu, Manuel de Conchyl., II, 1862, p. 23, fig. 102. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 3 Abth., p. 59, No. 3, pi. 5, figs. 9-11. Siliqua — — Mori.et, Journ. de Conchy]., vol. 37, 1889, p. 172, No. 8«. — — — Ed. v. Martens, Süss- u. Brackwasser-Mollusken d. Ind. Achip., 1897, p. 260. — — — Dautzenberg et Fischer, Journ. de Conchyl., vol. 54, 19U6, p. 220. Kampot (Golfe de Siam, L. Morlet). The Danish Expedition to Siam collected no specimens of this species. Distribution:— Madras, Tranquebar, Ceylon, Gulf of Manaar, Bombay to Ratnagiri, Mekran Coast. — Annam, Sumatra, Java, Flores, Celebes, Moluccas. 278 182 Siliqua minima, Gmel. Miniitissima legiiminiim, Chemnitz, Conchyl. Cabin., VI, 1782, p. 48, pi. 5, fig. 31. Solen minimus, Gmelin, Syst. Nat., ed. 13, 1790, p. 3227, No. 14. Aulas — — DuNKEH, Index molluscor. maiv Japon., 1882, p. 175. Machaera minima, — Cle.ssin in Mautini u. Chemnitz, Conchyl. Cabin., XI, 3 Abtli., p. 68, pi. 5, figs. 1—2. Siliqua — — E.V.Martens, Süss- u. Brackwasser-Moll. d. Ind. Archip., p. 262, No. 3. Machæra — — Hidalgo, Fauna malacol. de I. isl. Filipinas, II, p. 25. Solen pellncidus, Spengler, Skrivter af Naturhistor. Selsk., III, 2 H., 1794, p. 97, No. 13. — albida. Adams & Reeve, Zoology of the voyage of H. M. S. "Samarang," 1848, p. 84, pi. 23, fig. 15. Cultellus albidus, Dunker, Sowerby in Reeve, Conchol. icon., XIX, 1874, Cultellus, Sp. 16. Machaera albida, — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI, 3 Abth., p. 65, No. 13, pl. 18, fig. 3. The sound of Koh Chang, 3—5 fathoms (fragment). Distribution:— Malacca, Tranquebar, Bombay. — Philippines, China, Korea, Japan. Although I am almost convinced of the correctness of the determination, yet, on the basis of the small fragment of a young individual which is at hand, it cannot be settled with complete certainty, if the specimen does not possibly belong to the nearly allied species Sil. Winteriana, Dunk. Novaculina Siamensis, Mori. Novaculina Siamensis, L. Morlet, Journ. de Conchyl., vol. 37, 1889, p. 198, pl. 9, fig. 4. Solenocurliis (Novaculina) Siamensis. L. Morlet. P. Fischer, Catalogue d. Mollusques de I'lndo-Chine, p. 242. Noi'aciilina Siamensis, L. Morlet, Mission Pavie Indo Chine, 1879-1895, 111, 1904, p. 385, pl. 22, fig. 7. "Marais de Chanlakam" (Siam, Pavie). The Danish Expedition to Siam collected no specimens of this species. Solecurtus (Macha) rhombus, Spengl. Solen strigilatas var., Chemnitz, Conchyl. Cabin , VI, 1782, pp, 60—62, pl. 6, fig. 44. — Rhombus, .Spengler, Skrivter af Naturhistorie Selskabet, III Bd., 2 H., 1794, p. 1Ü2, Nr. 17. Solecurtus rhombus, Spengler, E. v. Martens, Süss- u. Brackwasser-Moll. d. Ind. Archip., p. 257, No. 2. Macha Quoyi. v. Martens, E. v. Martens u. B. Langkavel, Donuin Bismarckianum, 1871, p. 61, pl. 4, fig. 6 (non S. Quoyi, Deshayes = S. albas, Quoy & Gaim.). North of Koh Kahdat, 4—5 fathoms, coarse sand ('/a). Long. 35 mm., alt. 18 mm. Distribution: — Nicobars, Moluccas, Viti Isis., Kingsmill Isis. The figure in "Donum Bismarckianum" is not quite good; the outline both in Spengler's original specimen and in the specimen from Koh Kahdat is more squarish-oval, the anterior and posterior margins being almost rectilinear, obtusely truncated, and forming rounded angles with the dorsal and ventral margins. 183 279 Solecurtus (Mâcha) Philippinarum, Dunk. Mat-ha Philippiniinim, Dunkkh, I'roc. Zool. Soc. London, 1861, p. 424, No. 26. Holecurtus — — Sowerby in Rekve, Conchol. icon., XIX, Solecurlu.i, Sp. 12. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI, 3 Abtli., p. 90, No. 7, pi. 21, fig 8. Solenociirtus (Macha) Philippinarum, Du.nker, H. Crosse et P. Fischer, Jouni. de Conciiyl., vol. 40, 1892, p. 76, No. 25. Solecurtus Philippinarum. Dinker, E. v. Marte.ns, Süss- u. Brackwasser-Moll. d. Ind. Arcliip., 1897, p. 256. — — Hidalgo, Fauna nial. de 1. isl. Filipinas, II, 190.3, p. 26, No. 50. Macha — Dunker, Edg. Smith & Bloomer, Proc. Zool. Soc. London, 1906, II, p. 855. Golfe de Siam ("sur le littoral occidental du Cambodge," Pavie). The Danish Expedition to Siam collected no specimens of this species. Distribution: — Andamans, Wasin Isl. (East Africa). — Java, Philippines. In mentioning the genus Macha Edg. Smith (loc. cit.) says "Hermannsen (Indicis Gen. Malac. Vol. II p. 1) quotes Macha as de.scribed by Oken in 181Ô ; but I have searched in vain in the "Lehrbuch" (Lehrbuch d. Naturg. Vol. Ill) for any mention of this genus, which should therefore date from 1835." Herrmannsen himself had alreadv in the Supplement to "Indie, gen. Malacozoor." 1852, p. 78, corrected the date, in his statement concerning Oken's description of Macha, from 1815 to 1835. Solecurtus (Azor) emarginatus, Spengl. Solen anyustior constrictus etc., Chemnitz, Conchyl. Cabin., VI, 1782, p. 62, pi. 6, fig. 45. — coarctatus, Gmelin, Syst. Nat., ed. 13, 1790, p. 3227, No. 16 partim). Solecurtus (Azor) coarctatus (GmelinI, Edg. Smith, Report on the Lamellibranchiata of the Challenger Exped., 1885, p.. 79. Solen emarginatus, Spengler, Skrivter af Naturhist. Selskabet, III, 2 H., 1794, p. 105, No. 21 (non Synon. Pennant, Brit. Zool., IV, pi. 46, fig. 25 = i'. antiquatus, Pult.). Macha Scheepmakeri, Dunker, Zeitschr. f. Malakozool., 1852, p. 56, No. 11. Azor (Macha) Scheepmakeri, Uvnkkr, Novitates conchol., II, 1869, p. 121, No. 137, pi. 39, figs. 10 — 11. Solecurtus Scheepmacheri, — Sowerby in Reeve, Conchol. icon., XIX, Solecurtus, Sp. 14 — Scheepmakeri, — E. v. Martens, Suss- u. Brackwasser-Moll. d. Ind. Archip., p. 259, No. 3. Azor — — Hidalgo, Fauna raalacol. de 1. isl. Filipinas, 1903, II, p. 28, No. 53. Solecurtus abbreviatus, Gould, Proe. Boston Soc. Nat. Hist., VIII, 1861, p. 26. — — — Sowerby in Reeve, Conchol. icon., XIX, Solecurtus, Sp. 6. — — — J. DE Morgan, Bull, de la Soc. de France, X, 1885, p. 366, No. 24. Azor oblongus, Dunker, Proc. Zool. Soc. London, 1861, p. 425, No. 30. Solecurtus oblongus, "Dorhn," Sowerby in Reeve. Conchol. icon., XIX, Solecurtus, Sp. 2. Azor — Dunker, Hidalgo, Fauha malacol. de 1. isl. Filipinas, II, p. 27, No. 52. — solidns, Dunker, Proc. Zool. Soc. London, 1861, p. 425, No. 31. Solecurtus solidus (non Gray), Sowerby in Reeve, Conchol icon., XIX, Solecurtus, Sp. 3. W. of Koh Chuen, soft clay and mud (-/s). Sound of Koh Chang, 3—5 fathoms, soft clay C'/L'). W. of Koh Chang, 20-30 fathoms, mud and clay (5 + Vs). E. of Koh Mak (-/s). S. of Koh Kahdat ('/a). Between Koh Kahdat and Koh Kut, 6—10 fathoms, clay mixed with sand (1 + 's). North, west and south of Koh Kut, 10—30 fathoms, mud {^k). Long. 6—36 mm. 280 184 Siam (J. DE Morgan). Distribution: — Malacca, Poulo Penang, Andamans, Nicobars, Birma, Kaiikal (Coromandel, Dautzenberg), Mekran Coast, Gulf of Oman, (Gulf of Suez, Mac Andrew?) — Hong Kong, Philippines, Moluccas, New Guinea, Torres Strait. S. coarctatus, Gmelin, which in the course of time has indicated various species, viz. both tlie European S. antiquatiis, Pult., and the East Indian form, and has therefore caused some confusion, ought, in my opinion, to give place to Spengler's name emarginatus. Gmelin was evidently not clear with regard to his species, both his diagnosis (true, he says "medio coarctata," but does not mention more closely the characteristic depressed rays upon the middle of the valves), and his statement that "Solen anatinus, Linné" (non S. anatinus L. ^ Anatina subrostrata, Lam.), in Schröters's "Flussconchylien'" was synonymous with his species, show his uncer- tainty and that he has confused several species with the species in question, which he evidently did not know by personal observation. Spengler, in whose collec- tion the specimen was contained which Chemnitz^ in 1782 described and figured, gave in 1794 an exhaustive and accurate diagnosis of it under the name of S. emarginatus, and I think that this should be preferred to Gmelin's name. I rely upon Edg. Smith's authority in giving S. Scheepmakeri, Dunk., as a synonym of the species under consideration, though it attains a size that is probably not attained by S. emarginatus, Spengl. typ. As far as I can judge from the figure and the brief diagnosis Novaculina andamanensis, Preston,^ is nothing else but the present species. Fam. Gastrochaenidae. Gastrochaena gigantea, Desh. Fistulana gigctntea, Deshaves, Éncyclop. niéth. Hist. nat. d. vers., II, 1830, p. 142. Gastrochœna — — Traité élém. de Concliyl. (1834), pi. 2, figs. 6-8. lixplic. d. planches, p. 2. Tome 1, 2 part., p. 34. — — — SowERBY in Reeve, Conchol. icon., XX, 1878, Gastrochœna, Sp. 15. _ — — — Thesaur. Concliyl., V, 1887, p. 128, No. 4, pi. 470, fig. 12. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI, 4 Abtli. a, p. 13, No. 22, pi. 4, figs. 8— 9. Rocellaria — — Edg. Smith in The Fauna and Geography of the Maldive and Laccadive Archipelagoes, ed. by Stanley Gardiner, II, p. 626, No. 362. Gastrochaena — - Lamy, Bull, du Mus. d'Hist. Nat. Paris, 1906, p. 207. Gastrocluena lamellosa, Edg. Smith (non Deshayes), Report on the Lamellibranchiata of the Challenger Expedition, p. 28, pi. 7, fig. 2. Koh si Chang (1). Koh Chang, low tide (1). North end of Koh Chang, old coral blocks, 1 — 12 fathoms (13). South end of Koh Chang, 1 fathom, corals (1). Koh Kahdat, 1 fathom Ç/â). ' Schröter, Geschichte d. Flussconchylien. Halle 1779, p. 185, pi. 9, fig. 17. - MÖRCH, both in Malakozool. Blatter, 1870, p. 110, No. 21, and upon the label attached to Spengleh's original specimen, has given the name Solen constrictns, Chemn. 3 Records of the Indian Museum, II, Calcutta 1908, p. 209, pi. 16, tig. 40. 185 281 Long. 5—36 mm. Distribution: — Singapore, low water, boring in corals (Sv. Gad), Nancowry (Nicobars, Mus. Zool. Havn.), Maldive Archipelago (Edg. Smith). — Sorong (Tappa- RONE Canefri), Cape York (Challenger). Funafuti Atoll (Hedley as G. lamellosa, Desh., and with a reference to Edg. Smith, Challenger Lamellibr. loc. cit. Hedley adds that the Museum in Sydney has this species from Viti Isis., New Caledonia, Moreton Bay (Queensland) and St. Vincent's Gulf, Lord Hood's Isl. and Mangareva (Lamy). The specimens from Singapore were found in coral, in which they had made a bottle-shaped hole which was smooth interiorly, and only the narrow part of it which leads to the exterior is partially lined with a thin layer of chalk.' The form which Edg. Smith figures in Rep. Challenger Lamellibr. (loc. cit.) under the name of lamellosa, Desh., does not correspond with Deshayes's diagnosis of lamel- losa; some confusion must certainly, somehow or other, have taken place, I scarcely think I am wrong in putting Smith's form as a synonym of G. gigantea, Desh. Edg. Smith says, in his list of the Mollusca from Aden,- regarding Gastro- chaena dubia, Penn., "This species undoubtedly occurs in the Red Sea (ruppellii)^ at Singapore (indistimia, Desh.) and the Philippines (lamellosa, Desh.).^ On com- paring the types of the three Deshayesian species with specimens of G. dubia, I fail to discover any essential differences." I do not quite agree with Edg. Smith in this; G. gigantea from the Gulf of Siam and from Singapore differs from G. dubia, Penn., in the stronger and more prominent longitudinal striation over its whole surface, and gigantea attains a larger size than G. dubia, which has been recorded to reach only about 20 mm. Gastrochaena cymbium, Spengl. Gastrochœna cynihiiim, Spengler, Nye Saml. af d. kgl. danske Vidensk. Selsk. Skrifter, II, 1783, pp. 180— 82, figs. 12—17. — Beschäftig, d. Berlin. Gesellsch. Naturf. Freunde, II, 1776, p. 569, pi. IX A, figs. 3-5. Chœna Cymbium, — Retzius, Diss. sist. nova testaceor. genera, 1788, p. 20. — — — Skrivter af Naturliist.-Selskabet, III, 1 H., 1793, p. 24, No. 4, pi. 2, fig. 4. Lagenula — — Beck, MS. Mus. Univ. Hafn. Cucurbitala cgmbia, — Tryon, Proc. Acad. Nat. Sc. Philadelphia, 1861, p. 54. Fistulana /ajenu/a, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 436, No. 4. — éd. 2, VI, 1835, p. 31, No. 4. — — — Hanlev. Catal. of rec. biv. sliells, p. 3, pi. 13, fig. 59. Chœna {Cuciirbitnla) lagenula, Lamarck, Gould, Proc. Boston Soc. Nat. Hist., vol. 8, 1861, p. 22. Gastrochœna lagenula, Lamarck, Sowerby, Thesaur. Conchyl., V, 1887, p. 130, No. 24, pi. 470, fig. 18. ' The cave which G. dubia. Penn., forms is described and figured in: Magazin de Zoologie p. GuÉHiN-MÉNEViLLE, 1843 (par F. Caillaid), pi, 69 — 71, and in: Bucquoy, Dautzenberü et Dollfus, Moll, mar. du Roussillon, II, 1896, p. 607. - Proc. Zool. Soc. London, 1891, p. 395. = Comp.: Sturany, Lamellibranchiaten d. Rothen Meeres, 1899, p. 21. * As Edg. Smith apprehends this species in the Challenger-E.xped. Lamellibr. UK n. Viilensk. Selsk.Skr., 7. RæliUe, niiturvidensli. oK matheni. AW. V. 3. 3(i 282 186 Gastrochœna lageniila, Lamarck, Sowerby in Reeve, Conchol. icon., vol. 20, Gastrocbœna, Sp. 18, pi 3, fig. 16 (not fig. 18 = G. ouata, Sow.).' — pupina. Deshaves, Proc. Zool. Soc. London, XXII, 1854, p. 326, No. 39. — — — Sowerby, Thesaur. Conchyl., V, 1887, p. 130, No. 25, pi. 470, fig. 16. — — — — in Reeve, Conchol. icon., vol. 20, Gastrochœna, Sp. 17. Gastrocliaena destiayesi, Sturanv, Lamellibranchiateii d. Rothen Meeres, 1899, p. 19, pi. 5, figs. 1 — 7. NW. of Koh si Chang, 10 fathoms, mud (4). Between Koh Mesan and Cape Liant, 5 — 9 fathoms (6). Between Koh Mesan and Koh Chuen, 25 — 38 fathoms (4). S. of Koh Chuen, 30 fathoms, shells (1). W. of Koh Chang, 20 fathoms, mud (1). E. of Koh Mak, 20 fathoms, mud (3). W. of Koh Kut, 15 fathoms, mud (3). Coast of Koh Kut (1). Long. 12 mm. Distrihution: — Coromandel Coast, Ceylon, Red Sea, Suez. — Hong Kong, Moreton Bay. Gastrochaena aequabilis, Sluiter,' from Krakatau is closely allied to the present species. As Spengler's original specimens of G. cymbiuin have been at my disposal I am certain of the correctness of the determination. Fam. Pholadidae. Pholas (Monothyra) orientalis, Gm. Pbolas orientalis, Gmelin, Systema Naturae, ed. XIII, 1790, p. 3216, No. 7. — — — Lamarck, Hist. nat. d. anim. s. vert, V, 1818, p. 444, No. 2. — éd. 2, VI, p. 44, No. 2. Dactglina — — Gray, Ann. & Mag of Nat. Hist., 2 ser., VIII, 1851, p. 382. Pilotas Orieiitalis, — Sowerby, Thesaur. Conchyl., II, p. 486, No. 4, pi. 102, figs. 3-4. Monotliyra orientalis, ÜxMelin, Thyon, Proc. Acad. Nat. Sc. Philadelphia, 1862, p. 205. — Catalogue of rec. Moll. Plioladacea, p. 3. Pilotas — — Reeve, Conchol. icon., XVIII, Pholas, Sp. 5. Phragmopholas orienlalis, Gmelin, Morlet, Journ. de Conchyl., vol.37, 1889, p. 173, No. 91. Pholas {Dactylina) — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd , 4 Abth., p. 12, No. 6, pL2, figs. 3-4. — Indiae Orientalis, Chemnitz, Conchyl. Cabin., VIII, 1785, p. 35G, pi. 101, fig. 860. ' On PI. 3 in "Conchologia iconica" the numbers of No. 16 (G. ovata from Panama) and No. 18 (G. lagenula from Ceylonl, have been interchanged bj' a misprint; this has misled Sturany (who did not discover the error), so that he (loc. cit.) has established his species G. Deshayesi upon typical specimens of G. cgmbium, Sp. {lagenula. Lam.). It is not surprising that Clkssin should copy this error in his Monograph, without comparing the diagnoses with the figures, when we recall the uncritical character of his Monographs of Bivalves in: Martini u. Chemnitz, Conchyl. Cabinet. Hedi.ey (Australian Museum, Sydney. Memoirs III, 1896—1900, p. 508) characterizes Clessin's Monograph of "The Teredinidœ" as follows: "Even worse is an alleged Monograph bj' Clessin in the Conchylien Cabinet, of which the te.\t and illustrations disgrace that serial. The latter memoir is absolutely the worst zoological mono- graph I have read." -' C. P. Sluiter, lieber d. Bildung d. Kalkröhren von Gastrochaena. Natuurk. Tijd.schrift v. Nederl. Indie, 50 Bd., 1890, pp. 45-60, pi. 1. 187 283 Pholas Siamensis, Si'engler, Nye Saml. af Danske Vidensk. Selsk. Skrivter, III, 1788 (1784), pp. 128—38 with pi. (without Latin name). — Skrivter af Naturhistorie-Selskabet, II, 1 H., 1792, p. 88, No. 3. "Den Siamske Havbugt, for Udløbet af Strømmen Queda, hvor den gaaer op til Alaslav" (Spengler). Islands in the Gulf of Slam (Morlet). The Danish Expedition to Slam brought home no specimens of this species. Distribution: — Tranquebar, Gulf of Manaar, Mouths of the Indus (Karachee, Scinde), Oman. — China Sea. MÖRCH ' has shown that Sciitus {^) abnormis, G. and H. Nevill,- from Penang and Chandpur (Bay of Bengal) is nothing else but the accessory dorsal plate ("Protoplaxe") of P. orientalis, Gm. Pholas (Barnea) Australasiae, Gray. Barnia Atistrahisiir, Gray, Annals and Mag. Nat. Hist, 2 Ser., VIII, 1851, p. 38L Pholas — — SowEKBY, Thesaur. Conchyl., II, p. 488, No. n, pi. 107, fig. 73. Barnea — — Tryon, Proc. Acad. Nat. Sc. Philadelphia, 1862, p. 207. Pholas .— — Reeve, Conchol. icon., XVIII, P7io/as, Sp. 11. — — — Morlet, Journ. de Conchyl., vol.37, 1889, p. 173, No. 89. — (Barnea) Australiasae, Sowerby, Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 4 Abth., p. 21, No. 18, pi. 6, fig. 2. Barnea australasiae, Sowerby, Pritchard and Gatliff, Proc. Roy. Soc. Victoria, vol. Ki, p. 98. Between Bangkok and Kampot (Gulf of Siam), Morlet. The Danish Expedition to Siam brought home no specimens of this species. Distribution:— "Abundant in Australia" (Sowerby), Victoria (Pritchard and Gatliff), Spencer's Gulf (South Australia, Angas), Tasmania (Tate and May). A nearly allied species from Mergui has been described by Philippi under the name of Ph. birmanica.-^ On considering the distribution of P. Australasiae, a doubt arises as to the correctness of Morlet's determination. Pholas (Barnea) sp. ? The shell of a small Barnea (long. 5 mm.) has been obtained at Koh Kahdat which in form and sculpture somewhat resembles B. parva, Penn. On account of its small size and bad state of preservation I cannot determine it with any certainty. Pholas (Martesia) striata (L.), Sow. Pholas striatus, Linné, Syst. Nat., ed. X, 1758, p. 669, No. 12. - ed. XII, 1767, p. 1111, No. 22. — striata, — Sowerby, Genera of rec. and foss. shells, No. XXIII, Pholas, fig. 2. — Thesaur. Conchyl., II, 1855, p. 494, No. 29, pi. 104, figs. 40-42; pi. 105, figs. 43-44. — — — Forbes & Hanley, British Mollusca, I, p. 120. ' Journal de Conchyliologie, vol. 24, 1876, p. 367. - Journal of the Asiatic Soc. Bengal, vol.43, pt. II, 1874, p. 28, pi. 1, fig. 12. ' Abbild, u. Beschreib, neuer od. wen. gekannt. Conchylien, III, p. 51, pl. 1, fig. 1. 36- 284 188 Afar/esiasfri'afa, Linné, H. & A. Adams, Genera of rec. Moll., II, p. 330, pi. 90, fig. 5. Pholas — — P. Fischer, .Journ. de Conchyl., VIII. 1860, p. 337. Martesia — — Tryon, Proc. Acad. Nat. Se. Philadelphia, 18ti2, p. 220. — Catal. of rec. Moll. Ord. Pholadacea, p. 10, No. 13. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 4 Abth., p. i5. No. 13, pi. 10, figs. 2—3 and 7-8. Pholas {Marlesia) striata L., E. v. Martens, Süss- u. Brackwasser-Moll. d. Ind. Archip., 1897, p. 281. Martesia striata, Linné, Hedley, Australasian Assoc. Adv. Science, VIII, 1901, p. 249, pi. 10, figs. 10—11. Pholas pusillus, — Syst. Nat., ed. X, 1758, p. 070, No. 14. — Lignorum, Spengler, Beschäft. d. Berl. Gesellsch. Naturf. Freunde, IV, 1779, p. 167, pi 5, figs. 1 — 5. — Skrivter af Naturh. Selsk., II, 1 H., 1792, p. 95, No. 9 Pholas pusillus;. ^- nana, Pulteney, Catal. of the Birds, Shells, etc. of Dorsetshire, 1799, p. 27. — clavata, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 446, No. 9. — éd. 2, VI, p. 46, No. 9. — conoides, Fleming, History of Brit, animals, 1828, p. 457. — falcata, Wood, Gener. Conchology, 1835, p. 84, pi. 16, figs. 5 — 7 (fide Tryon). — semicostata. Lea, Proc. Boston Soc. Nat. Hist., 1, 1844, p. 204 (pi. 24, fig. 1). — terediniformis, Sowerby, Proc. Zool. Soc. London, XVII, 1849, p. 161, No. 5. — Thesaur. Conchyl., II, p. 490, No. 18, pi. 108, figs. 97— 98, P. Teredinœformis (fide Tbyon). Near Koh Samit and Koh Tulu (boring in the swampy layer of cocoanuts which float upon the surface of the water). West of Koh Chang (boring in the fruits of Terminalia Catappa L., which float upon the surface). Only small specimens as much as 5 mm. in length. Between Bangkok and Kampot in the Gulf of Siam (Morlet). Distribution: — Singapore, Pulo Penang, Mergui Archip., Burma (in the trunks of the teak-tree), Madras, Tranquebar, Gulf of Manaar, Bombay, Aden, Ins. Zanzibar, Mozambique. — Annam, southern China Sea, Japan, Philippines, Borneo, Batavia and Molluccas (in piles), Arafura Sea, Cape York, Cooktown (Queensland), Sydney, New Caledonia. — East coast of America: South Carolina, Florida, Bermuda Isis., Texas, Greater and Lesser Antilles (Guppy and Gabb record it from pliocene formations on Trinidad and in Costa Rica), South America as far as Rio de Janeiro. — The coasts of Europe, e. g. along England and France and in the Mediterranean it has been taken in floating timber and boring in ships. Spengler's original specimens' of P. lignorum from Tranquebar agree precisely with the specimens of P. striata L. from St. Thomas. Several other boring forms such as Naranio lapicida, Chemn., Coralliophaga coralliophaga, Chemn., Modiolaria coralliophaga (Chemn.) Gmel., Lithodomus cinnamomea, Chemn., and others have almost the same wide and peculiar geographical distribution as the present species. In the above-mentioned cocoanut from Koh Samit many quite young, living specimens, 3 — 5 mm. in length, were found, without Galium, and of the accessory plates only a "Protoplaxe" is found, which in form differs from those of the full-grown individuals." ' In the Zoological Museum of the University of Copenhagen. ^ See P. Fischer: "Études sur I. Pholades," Journ. de Conchyliologie, VIII, 1860, p. 340. 189 285 Pholas (Martesia) multistriata, Sow. Pholas muUistriata, Sowehby, Thesaurus Conchyl., II, 1849 (1855), p. 494, No. 28, pi. 104, figs. 35- 36. - Proc. Zool. Soc. London, 1849, p. 162, No. 8. Martesia — ^ Tryon, Proc. Acad. Nat. Se. Philadelphia, 1862, p. 218. Pholas — — Reeve, Conchol. icon., XVIII, Pholas, Sp. 37. Martesia — — Morlet, Journ.de Conchyl., vol. 37, 1889, p. 173, No. 92. — — — P. Fischer, Catalogue d. Moll, de I'lndo-Chine, p. 244. — — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Ud., 4 Abth., p. 42, No. 8, pi. 7, flgs. 6-7. Mékong, Gulf of Siam (Morlet). The Danish Expedition to Siam did not collect any specimens of this species. Distribution: — Cua-Quen, Annam (Crosse & Fischer), Turtle's Island, N. coast of Australia (Sowerby). Pholas (Martesia) Gray ana, Leach. Photas Grayana, Leach, MS. Brit. Mus. — — — Reeve, Conchol. icon., XVIII, Pholas, 1872, Sp. 46. Martesia — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 4 Abth., p. 45, pi. 11, fig. 2. North end of Koh Chang, old coral blocks, 1 — 12 fathoms (^/s). Long. 5 — 10 mm. Distribution unknown. My specimens, which are all small and were taken dead, are without "Callum" upon the anterior end. The striped sculpture upon the front end is very regular, close-set and fine ; it is slightly wavy, owing to several grooves which radiate from the umbones. Pholas (Martesia) rivicola, Sow. Pholas rivicola, Sowerby, Thesaurus Conchyl., II, 1848 (1855), p. 496, No. 33, pi. 108, figs. 90— 91. — — — A. Adams and Reeve, Mollusca of the vojage of H. M. S. "Samarang," 1848, p. 84, No. 98, pi. 23, fig. 5. Martesia — — Tryon, Proc. Acad. Nat. Sc. Philadelphia, 1862, p. 219. Pholas — — Reeve, Conchol. icon., XVIII, Pholas, Sp. 22. Martesia — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 4 Abth., p. 44, No. 11, pi. 11, figs. 5-6. Pholas — - Morlet, Jouin. de Conchyl., vol. 37, 1889, p. 173, No. 90. — [Martesia] rivicola, Sowerby, E. v. Martens, Süss- u. Brackwasser-Moll. d. Indischen Archipels, 1897, p. 282. Martesia Ihtminalis, Blanford, Journ. Asiat. Soc. Bengal, 1867, vol. 36, p. 67, pi. 3, figs. 1—3 (fide E. v. Martens). Parapholas — — Stoliczka, Palæontologia Indica. Cretaceous Fauna of South-India, III, Pelecypoda, 1871, pp.20 and 24. — ? — — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 4 Abth., p. 50, No. 2, pi. 13, figs. 4-5. Between Bangkok and Kampot (Gulf of Siam, Morlet), Petshaburi in the Gulf of Siam (v. Martens). 286 190 The Danish Expedition to Siam brought home no specimens of this species. Distribution:— Mouths of the Irawadi (Blanford), Port Canning (Delta of the Ganges, Stoliczka), Orissa coast, Ceylon (Stoliczka). — Southern China Sea (8° N. lat., V. Martens), Borneo (A. Adams), Port Cuming (Australia, Collect. Rolle). Pholas (Parapholas) quadrizonatus, Spengl. Pholas quadrizonatus, Sfenülkr, Skrivtcr af Naturhistorie-Selskabet, II, 1 H., 1792, p. M'A, No. 8, pi. 1, figs. 1—3. — quadrizonalis, — Sowerby, Thesaurus Conchyl., II, 1855, p. 492, No. 23, pi. 1U8, figs. 88—89. Parapholas - — H. & A. Adams, Genera of rec. Moll., II, p. 330, pi. 90, fig. 4. - — — Tryon, Proc. Acad. Nat. Sc. Philadelphia, 1862, p. 215. Pholas quadrizonalus, — Mörch, Malakozoolog. Blätter, XVII, p. 104. ' — quadrizonalis, — Reeve, Conchol. icon., XVIII, Pholas, Sp. 38. Parapholas — — Clessin in Martini u. CuEMNrrz, Conchyl. Cabin., XI Bd., 4 Abth., p. 55, No. 7, pi. 14, fig. 1. Pholas Incii, Sowerby, Proc. Zool. Soc. London, XVII, 1849, p. 161, No. 7. — — — Thesaurus Conchyl., II, 1855, p. 491, pi. 105, figs. 45 46. — Incei, — Reeve, Conchol. icon., XVlII, Pholas, Sp. 30. Parapholas Incei, — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 4 Abth., p. 52, No. 4, pi. 12, figs. 9-10. Pholas striaius, Chemnitz (non Linné), Conchyl. Cabin., VIII, 1785, p. 364, pi. 102, figs. 864—66 [Pholas clavata, Lam. c). South-west end of Koh Chang, 1 fathom, coral (1). North end of Koh Chang, old coral blocks, 1 fathom (1). Long. 13 mm. Distribution: — Mergui Archip. (v. Martens), Aden (Shopland). — Torres Strait (Sowerby). One of the specimens from Koh Chang is a young individual; it is entirely without "Callum" and resembles therefore most nearly a Zirphaea." Fam. Teredinidae. Teredo Manni, Wright. Kuphus ?) mannii, Wright, Transact. Linn. Soc, vol. 25, 1866, p. 565, pi. 65, figs. 1 — 8, Nausitoria manni, — Hedley, Australasian Assoc. Advancem. Science, VIII, 1901, p. 248. Sound of Koh Chang, 5 fathoms. Several very small specimens (about 0"7 mm.) boring in a piece of wood. Distribution: — Singapore, Cooktown (Queensland). ' It is due to a mistake that Mörch (loc. cit.) says "Spengler citirt mit Unrecht Chemn. f. 864 — 66, die eine Martesia ist," as it is the same specimens from the collection of Spengler, which Chemnitz 1785 describes and figures (under the name of P. striatus L. ?) and Spengler afterwards (1792) de- scribes as P. quadrizonatus. These specimens are still in existence in the Museum of the University of Copenhagen. ^ vide: P. Fischer, Études sur 1. Pholades, Journ. de Conchyliologie, VII, pp. 173 — 74. 191 287 On account of the small size of the specimens the determination is somewhat uncertain. The "palettes" bear a great resemblance to the figures by Whight (loc. cit.). Note. At Singapore in shallow water a solitary valve of a Nattsitora has been taken (by Sv. Gad), probably N. edax, Hedley (Proc. Linn. Soc. New South Wales, IX, 1894, p. 501, pi. 32, figs. 1—5), but as its palettes were not found, the determination is uncertain. Fam. Pandoridae. Coelodon elongatus, Carp. Coelodon elongatus, Carpenter, Proc. Zool. Soc. London, 1864, p. 600, No. 3. — — — Edg. Smith, Rep. Lamcllibranchiata of the "Challenger" E.xped., p. 62. Pandora elongata, — G. B. Sowerby in Reeve, Conchol. icon., vol. 19, 1874, Pandora, Sp. 4. Sound of Koh Chang, 5 fathoms, soft clay (1 + ^h). Long. 11 — 16 mm. Distribution: — China, Borneo, Flinders Passage (North Australia). The present species is very characteristic on account of its flatness, but like all the species belonging to the genus Pandora it varies considerably in form. Hedley evidently does not know Sowerbv's figure in Reeve's Conchol. icon, as he calls it (Proc. Linn. Soc. New South Wales, vol. 31, 1906, p. 473) an "unfigured species" and (loc. cit. pi. 37, fig. 16) gives a figure of a form from Mast Head Reef, Queensland, under the name of C. elongatus, Carp., which, however, scarcely is Carpenter's species. Note. Myodora trigona, Reeve, has been taken (by Sv. Gad) at Singapore in shallow water. Fam. Anatinidae. Anatina anatina L. Solen anatinus, Linné, Syst. Nat, ed. X, 1758, p. 673, No. 30. — ed. Xll, 1766, p. 1115, No. 40. - ed. XIU, p. 3225, No. 8. — Museum Ludov. Ulrica; reg., 1764, p. 475, No. 18. — — — CHEMNrrz, Conchyl. Cabin., VI, 1782, p. 62, pL 6, figs. 46-48. Anatina subrostrata, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 463. — éd. 2, 1835, VI, p. 78. — — — Reeve, Conchol. icon., XIV, Anatina, Sp. 0. — ■ — — Savigny, Descript. de I'Egj'pte. Mollusques, pi. 7, fig. 8. — siplionata. Reeve, Conchol. icon., XIV, Anatina, Sp. 2. — — — Edg. Smtfh, Lamellibranchiata of the "Challenger" Exped., p. 76. — flexuosa. Reeve, loc. cit., Sp. 5. amphora, Reeve, loc. cit., Sp. 23. — eximia. Reeve, loc. cit., Sp. 30. N. of Koh Kam, 5 fathoms, gravel (1). Koh Chuen, 30 fathoms (2). Between Koh Mesan and Cape Liant, 9 fathoms (2). S. of Koh Tulu, 10 fathoms, mud mixed with sand (1). Off Tung Kaben, 6 fathoms, mud mixed with sand (2). Sound of Koh Chang, 3 — 5 fathoms, soft clay (many fragments). Between Koh Kahdat 288 192 and Koh Kut, 6 fathoms, clay mixed with sand (1). W. of Koh Kut, 15 fathoms, mud (2). Off Koh Kut, 5 fathoms (fragments). Long. 26 mm. (several of the fragments have belonged to larger specimens). Distribution: — Singapore (Danish Exp. to Siam, 2 specimens), Nicobars, Ceylon, Mekran Coast, Aden, Red Sea, Suez, Suez Canal. — Philippines, Japan {A. flexuosa), Borneo, Flores. The species here under consideration varies considerably, especiallj' with regard to the form and the development of the rostrum; and many species of the gen. Anatina will certainly in the course of time be withdrawn owing to their having been based upon entirely individual characters. The greater part of the specimens from the Gulf of Siam resemble most nearly Reeve's figure of A. eximia. Fam. Clavagellidae. Brechites dichotomus, Chenu. Asperyilliim dicbotomum, Chenu, Illustrations couchvliologiques il813- 45), Aspergillum, p. 3, pi. 2, fig. 6. Brechites dichotomus, — H. & A. Adams, Genera of rec. Moll., II, 1858, p. 339. Aspergillnm dichotomutn, — Reeve, Conchol. icon., XII, ISOO, Aspergillum. Sp. 9. Penicillus dichotoma, — Tryox, Proc. Acad. Nat. Sc. Philadelphia, 1861, p. 59, No. 2. Aspergillum dicholomum, — Clessin in Martini u. Chemnitz, Conchyl. Cabin., XI Bd., 4 Abth. A, p. 30, No. 9, pi. 12, fig. 2. Koh Lan, 30 fathoms, mud (1). Koh Chuen, 30 fathoms (3). N. of Koh Kahdat, 4—5 fathoms, coarse sand (1). Koh Kahdat, 1 fathom, sand (1). S. of Koh Mak, 5-6 fathoms (2). All the specimens collected were fragmentary. Distribution: — Singapore (Cuming), Gulf of Manaar (Thurston). Tryon (Ioc. cit.), undoubtedly correctly, considers B. disjunctus, Desh., to be synonymous with B. dichotomus, but several other of those species which have been established ought probably also to be abolished; thus Gray^ has united under the name of Penicillus aquaria, Burr. : — Aspergillum dichotomum, Chenu, semißmbriatum, Chenu, sparsum, Sow., javaniim. Gray (non Lam.). Order Septibranchiata. Fam. Cuspidariidae. Neaera Singaporensis, Hinds. Neœra Singaporensis, Hinds, Proc. Zool. Soc. London, XI, 1843, p. 77. W. of Koh Chuen, soft clay and mud ('/a). W. of Koh Chang, 30 fathoms (1/2). Koh Kahdat (''/s). N. of Koh Kut, 10 fathoms, mud (%). Between Koh Kahdat 1 Proc. Zool. Soc. London, 1858, p. 312. 193 289 and Koh Kut, 6—10 fathoms, clay mixed witli sand and shells (-/^). W. of Koh Kut, 15 fathoms, mud (1). Long. 4—9 mm. Distribution: — Singapore. NeaeraiCardiomija) pulchella, H. Ad., ' and N. Gouldiana, Hinds," are closeh' allied to . ' 'r^ the present species. Neaera Singaporensis, Hinds. Neaera rosea, Hinds. Necera rosea, Hinds, Proc. Zool. Soc. London, XI. 1843, p. 78. — — — Mollusca of the Voyage of H. M. S. "Sulphur," 18i5, p. 70, No. 296, pi. 20, fig. 20. — — — HiuALGo, Fauna malacol. de I. isl. Filipinas, 1903, p. 43, No. 88. West of Koh Kut, 30 fathoms, sand and mud (V2). Long. 5 mm., alt. 3 mm. Distribution: — Philippines, New Guinea. I do not doubt that the small left valve which I have before me should be referred to N. rosea, Hinds, in spite of the fact that the beak is not of a rose-colour. ' Proc, Zool. Soc. London. 1870, p. 789, pi. 48, fig. 4, - Proc. Zool. Soc. London, 1843, p. 77. ERRATA Page 45, line 6, for Busch read Bush. - 128, - 42, - Lamellibranchiata - Lamellibranchiaten. - 134, - 9, - perofnata - personata. - 144, - 34, - T. variegatus. Sow. - T. variegatus, Hani. D. K. D. Viclonsk. Selsk. Skr., 7. I\;ikkc. nalur vidcnsk. og nl.^lllenl. Afd. V. 3. 37 Index. Page Abra alba, Wood 84 Acanlhocardium sec Cardium. Acar see Area. Aeiiigma see Anomia 11 Aloidis see Corbula. Amphideswa amabilis. A. Ad. . 117 — casta, A. Ad 118 Amussium Balloti, Bern 62 — pauciliiata, H.A.Sm. 61 — pleuronectes, Linné 62 Amygdale see Tapes . . 143, 144 Anadara see Area. Anaitis calophjlla, Phil 150 — foliacea, Phil 151 — isabellina, Phil 151 Anatina amphora, Reeve . 191 — anatina, Linné 191 — eximia, Reeve 191 — flexuosa, Reeve.. 191, 192 — siphonata. Reeve .... 191 — subrostiata. Lam. 184, 191 Anatinella Nicobarica, Gm. . 129 AnguUis see Tellina. Anodontia see Lucina 71 — globosa. Forsk 79 Anomalocardia see Area. — oblonga, Phil. & Dunk. . . 17 Anomia aenigmatica, Ch 11 — aniabaeus. Gray . . 10, 11 — convexum, Koch 11 — coiTugatum, Koch .. . . 11 — dryas, Gra3' 10, 11 — placenta, Linné 11 — plenilunium, Reeve. . . 10 — reticulatum, Koch . . 11 — roseum. Gray 11 Sella, Gmel 12 ~ sol, Reeve 10 Page Anomiidae 10 Antigona lamellaris, Schum. . 149 — reticulata, Linné 150 Area aceraea, Mel v. & Stand. . 17 — afra, Gmel. var. solida, Sow. 19 — americana, Graj' 31 — Americana, d'Orb 14 — antiquata, Linné var. sub- rubra. Dunk . 23 — Arabica, Forsk. (Phil.) . 14 — attenuata. Dunk 18 — auriculata, Lam 25 — auriculifera, Lam 32 — bicarinata. Sow 14 — bicolorata, Ch. 15 — Brandti, Phil 26 — campechensis. Gm 31 — Candida, Gmel 16 — Cecillei, Phil 24, 25 - chalcanthum. Reeve 30 — clathrata. Reeve 27 — complanata, Ch 15, 18 — concamerata. Mart 32 ~ congenita, E. A. Sm 21 — consociata, E. A. Sm 28 — cornea, Reeve var. Cecillei (Phil.), Lamy 24, 25 — crebricostata. Reeve 27 — cruciata, Phil 15 — cucullata. Mart 32 — Cucullus, Gm 32 — cunealis. Reeve 14 — cuneata. Reeve 14 — decussata, Lischke 19 — — Sow. ... 15, 16, 17 — dichotoma, Desh 29 — — — var. gra- tiosa m 29 — disparilis, Reeve 26 Page Area divaricata. Sow. 20, 21 — Domingensis, Lam. . . 20, 21 — donaciformis, Reeve 21 — dubia, Baird 21 — foliata, Forsk 16 — fusca, Brug. . . 15 — fusco marginata. Dunk. 13 — globosa. Reeve 26 — gradata, Brod. & Sow. 20, 21 — granosa, Linné 22, 23 — granulata, Phil 17 — granulosa, Linné var. mi- nuta, M. v. Neumayer 22 — granulosa, Jonas 32 — gubernaculum, Reeve... 29 — Helblingi, Ch 16 — hispida, Phil 26 — holoserica. Reeve 24, 25 — imbricata, Brug 14 — — Poli 23 — inaequivalvis. Brug 26 — Indiae Orientalis, Ch. ... 30 — indica. Gm. 30 — Kraussi, Phil 14 — lactea, Linné 17, 19 — — — var. ery- thraea, Issel 17 — laminata, Angas 21 — lima. Reeve 17 — Unter. Jonas 13, 14 — Luzonica, Reeve 30 — M'Coyi, Ten.-Woods 21 — maculata. Sow 14 — mollis. Dunk 21, 22 — Mortenseni, n. sp. ..... 24 — multistriata, Forsk 33 — mutabills. Sow 14 — navicularis. Brug 13 — nivea, Ch 16, 17 195 291 Page Area nodifera, v. Martens 23 — oblonga, Dunk 17, 23 — — Phil 22, 23 — obliquata, Gray 19 — olivacea, Reeve 19 — parva, Sow 18 — paucigranosa. Dunk 23 — pectunculiformis, Dunk. . 19 — pectunculus, Linnc' 32 — Petersi, Dunk 16 ^ pholadiformis,C. B.Adams 21 — pisolina. Lam 19, 20 — plicata, Ch 20, 21 — pulchella. Dunk 23 — — Reeve 23 — pusilla. Sow 21 — pygmaea, H. Adams .... 27 — reticulata, Cli 21 — revelata, Desh 16 — rhomboidalis, Ch. . 26 — Rodatzi, Dunk. 15 — rotundicostata, Reeve . 28 — Sabinae, Mori. 29 — scapha, Ch 24 — sculptilis. Reeve 16, 19 — semitorta. Lam 31 — Siamensis, n. sp. 18 — signata. Dunk 14 — solida. Sow. 19, 20 — squamosa. Lam 20, 21 — subquadrangula. Dunk. . 13 — subi-ubra, Dunk 23 — tenebrica. Reeve 20 — tenella. Reeve 21 — torta, Steenstr 31 — tortuosa, Linné 31 — trapezina. Lam 17 — Troscheli, Dunk 28 — umbonata, Lam 14 — uropygomehina, Bory ... 24 — velata, Sow 16, 17 — •vellicata, Reeve 26 — Zebuensis, Reeve 19, 20 Arcidae 13 Arcopagia see Tellina. Argina see Area 30 Artemis contusa. Reeve 154 — cretacea, Reeve 154 — exasperata, Pliil 153 — lamlnata, Reeve 152 — pubescens, Phil 155 — simplex, Hani 154 Page Artemis trigona, Reeve 152 Asaphis arenosa, Rumph. 114 — coccinea, Marty n .... 113 — deflorata. Linné 113 — dicliotoma, Anton .... 114 — rugosa, Lam 114 — violascens, Forsk 113 /Ispergi'/Ziimdicliotomum, Chenu 192 Astartidae 68 Atactodea see Mesodesma 122 Aldus minimus, Gm 182 Avieula see Pleria. Azor coarctatus. Gm 183 — emarginatus, SpengI 183 — oblongus, Dunk 183 — Scheepmakeri, Dunk. ... 183 — solidus. Dunk 183 Barbatia see Area. Barnea sp. '? 187 — Australasiae, Gray .... 187 — parva, Penn 187 Belhicina 78 Botula see Lithodomus 42 Brachyodontes emarginatus, Bens. (Reeve) 39 — subramosus, Hani 38 Brechites dichotomus, Chenu. . 192 — semifimbriatum, Chenu 192 — sparsum. Sow 192 — javanum. Gray 192 — disjunclus, Desh 192 Bacardium see Cardium. Byssoarca see Area. Caeeella Cumingiana, Desh... 130 Callianassa 85 Callista citrina, Rochebr 132 — guttata, Rom 133 — inflata. Sow 131 Calloeardia Desliayesi, Pfr. var. 133 — guttata, A. Ad 133 Capsa deflorata, Linné 113 — ellorata, d'Orb 113 — rugosa, Lam 113 Capsella violacea, Reeve 117 Capsula rugosa, Lam 113 Cardiidac 157 Cardilia inermis, Desli 121 Cardiliidae 121 Cardiomya pulchella. H. Ad. .. 193 Cardita calyculata. Lam 67 — dactylus, Brug 70 Page Cardita radula. Reeve 67 — subaspera, Lam 67 — variegata. Brug 67 Carditella infans, E. A. Sm. . . 68 — pulchella, n. sp 68 — pusilla, n. sp 68 — Torresi, E. A. Sm. . . 69 Carditidae . 67 Cardium Adamsi, Reeve 166 — amboinense. Gm 32 — Annae, Pilsbry 162 — apertum, Ch 162 — arenieola, Reeve 161 — Asiaticum, Brug 159 — Australe, Sow 163 — Carditaeforme, Reeve 165 — coccinea, Marty n .... 113 — coronatum.Spengl. 159, 163 — Dupuchense, Reeve 160, 161 — fimbriatum, Wood... 159 — flavum, Linné 160 — fragum, Linné 165 — — — var. carinata m. 165 — — Linné var. Sueziense, Issel ... 158 — Hungerfordi, Sow. ... 163 — hystrix, Reeve 166 — imbricatum. Sow. . . 166 — impolitum, Sow 161 — lamellatum, Speugl. . 159 — latum, Ch 158 — lima, Spengl 159 — lobulatum, Desh 164 — maculosum, Sow 161 — magnum, Ch 160 — multispinosum, Sow. 160 — muticum. Reeve 162 — papyraceum, Ch 162 — pectiniforme. Born 160,161 — pulchrum, Reeve ... 163 — retusum, Linné 164 — rugatum, Gron 162 — rugosum, Lam. , 160, 161 — setosum, Redf. 157 — Sinense, Sow 160 — subretusum. Sow. 164 — Sueziense, Issel 158 — tenuicostatum, Lam.. 164 — transcendens, Melv. & Stand 161 — unedo, Linné 164 37* 292 196 Page Cardium virgo. Reeve 166 Caryatis affinis, Gm. var. in flata, Sow 131 — crocea, Desh 133 — Deshayesi, Pfr 133 — hebraea, Lam 131 — isoeaidia, Sow 133 — minuta, Koch 132 — striata, Gray 132 . — Yerburyl, E, A. Sm., . 133 Chaena cymbium, SpengI 185 lagenula, Lam 185 Chama eoralliophaga, Cli 70 — cornuta, Ch 169 — cristella, Lam 168 — florida, Lara 169 — fragum, Reeve 168 — granulata, Cless 168 — multisquaniosa, Reeve 42, 167 — oblonga, Linné var. ... 69 — piilchella, Reeve 169 Reeveana, Cless. . 168, 169 Chamidae 167 Chione calophylla, Phil 150 Cochinensis, Sow 148 — embrittles, Melv.&Stand. 152 — foliacea, Phil 151 — hizenensis, Pilsbry .... 147 imbricata. Sow 148 — isabellina, Phil 151 — Jukesi, Desh 151 — Lamarcki, Gray 150 — lamellaris, Schum 149 — lionata, E. A. Sm 149 — marica, Linné (Sow.) 146, 147 — micra, Pilsbry 148 — recognita, E. A. Sm. 146, 147 — reticulata, Linné 150 — scabra, Hani 148 — Siamensis, n. sp 148 — striata. Gray 132 — subnodulosa, Hani 147 — toreuma, Gould 151 Chlamys see Pecten 61 Chloromya sec MytUus. Choristodon divaricatum, Ch. . 157 — lapicidum, Cli. . . 157 Circe aequivoca, Sow 139 — arnica, E. A. Sm 136 — Artemis, Desh 134 — dispar, Ch 139 Page Circe divaricata, Cli 139 — fulgurata. Reeve 134 — gibbia. Lam 138, 140 — hebraea, Lam 131 — lirata, Rom 135 — Melvilli, n. sp 135 — Metcalfei, Desh 134 — nana, Melv 135, 136 — pacta, Rom 134 — pectinata, Linné. . . . 138, 140 — personata, Reeve 134 — picta. Lam 136 — plebeja, Hani 134 — scripta, Linné 134, 153 — sugillata, Reeve 134 — sulcata. Gray 134 — sulcatina. Lam 137 — trimaculata, Lam 137 — undatina. Lam 134 Circomphalus see Chione 150, 151 Clavagellidae 192 dementia papyracea, Gray 156 Codakia see Lucina. — bella delicatula, Pilsbry 74 Coelodon elongatus, Carp 191 Coralliophaga caiditoidea, Blainv. 71 — coralliophaga, Ch. 70, 188 — dactj'Ius, Rrug. . . 70 — laminata. Reeve 71 — lithophagella. Dunk. 71 — striolata, H. Ad. 71 Corbula arcaeformis, n, sp. .. 172 — crassa. Hinds 169 — eburnea, Hinds. . 174, 175 — crythrodon. Lam 171 — fortisulcata, E. A. Sm. 174 — isomeros. Hinds 123 — Kjaeriana, C. B. Ad 172 — lineata, n. sp 171 — Macgillivrayi, E. A. Sm. 170 — (?) mirabilis, n. sp. . . . 175 — monilis, Hinds 174 ^- pallida, Hinds 171 — rugifera, A. Ad. (Sra.V 173 — scaphoides. Hinds 170, 171 — solidula. Hinds 174 ; I — subquadrata, Melv. . . 172 — sulcata. Lam 174 — Taheitensis, Lam 173 Page Corbnla tenuis. Sow.... 173 — tunicata. Hinds 170 Crassalella glabrata, Lam 122 — radiata, Sow 67 Crassatellidae 67 Cratena 85 Crenella nana. Dunk 43 Crista dispar, Ch 139 — divaricata, Ch 139 — gibbia. Lam 138 — pectinata, Linné 138 — Savignj'i, Jonas 138 Cryptodon bullulus, Reeve ... 72 — globosum, Forsk. . 80 Cri/pi^" København 1910 ,^' The crabs here described are the result of the exploration by Dr. Th. Mortensen of the eastern coast of the Gulf of Siam from Koh si Chang, near the head of the gulf, to Koh Kong at the south, in about 11° north latitude. The passages formed by the numerous islands fringing the mainland proved to be an excellent collecting ground. Operations were continued for a period of about four months (from December, 1899, to March, 1900) and from the shore line to a depth of 30 fathoms. The collection obtained is a large one, comprising 204 species, and prob- ably represents a large proportion of the fauna actually existing there. A few specimens- are from Singapore. The Gulf of Siam occupies a somewhat central position in the marine Asiatic fauna, being midway between the Chinese and Japanese seas on the one hand and the Indian Ocean on the other, while in an intermediate direction radiates the Malayan Archipelago. While the Brachyura are in general Indo-Pacific in character, 72 per cent of the previously known species being enumerated by Alcock in his "Materials for a Carcinological Fauna of India," yet there are certain features which seem to be peculiar to the Gulf of Siam. Of the twenty-seven new species, three represent as many new genera, and one makes necessary a new subfamily. Several of these forms are catometopous crabs with a semicircular carapace, that is, with a squarish posterior, and an arcuate anterior outline, the antero-lateral angles being rounded off. The collection is noticeably rich in species of this build, belonging to the families Gonoplacidœ (subfamilies Rhizopinœ and Hexapodinœ) and Pinnotheridœ. Next in importance are the Leacosiidœ which number 31 species. One is struck with the many minute specimens in the collection; their pre- sence may be attributed either to the zeal of the collector or to their relative abundance in this sheltered arm of the sea. The classification used in this paper is that of Borradaile (cf. Ann. Mag. Nat. Hist. (7), XIX, June, 1907, 457—486). In the case of species included in Alcock's memoir above mentioned,' synonymicai references are restricted to that work, which contains full synonymy and descriptions. The types of new species are in the Copenhagen Museum and a set of cotypes is in the United States National Museum. ■ Journ. Asiat. Soc. Bengal, LXIV, 1895; LXV, 18%; LXVII, 1898; LXVIII, 1899; LXIX, 1900. 39* 304 4 The new forms described are as follows: — Heteromicia mesanensis, sp. nov. Cryptocnemus mortenseni, sp. nov. Pliilyra olwacea, sp. nov. Arcania siamensis, sp. nov. Rhynchoplax coralicola, sp. nov. Cleistostoma lingnlatum, sp. nov. Camptandriiim paludicola, sp. nov. Acmœopleiira rotunda, sp. nov. Sesarma {Chiromantes) siamense, sp. nov. Pinnotheres härgeri, sp. nov. — lanensis, sp. nov. — qnadratus, sp. nov. — nigrans, sp. nov. — kamensis, sp. nov. — kutensis, sp. nov. — siamensis, sp. nov. Mortensenella forceps, gen. et sp. nov. Astlienog nathus hexagonum, sp. nov. Litocheira cristata, sp. nov. Megœsthesius sagcdæ, gen. et sp. nov. Typhlocarcinopsince, subfam. nov. Typhlocarcinops canaliculata, gen. et sp. nov. Thaumastoplax orientalis, sp. nov. — chuenensis, sp. nov. Lambdophallus anfractus, sp. nov. Pilumnus borradailei, sp. nov. Actumnus changensis, sp. nov. Heteropanope sexangula, sp. nov. In order to secure these new forms for this collection a preliminary descrip- tion of them was published in the Proceedings of the Biological Society of Washington, Vol. XXII, June 25, 1909, pp. 107 — 114, in a paper entitled "New Crabs from the Gulf of Siam." The following new names are given to previously known species: — Uca manii. Pinnotheres alcocki. Hypocolpus haanii. Portunus (Lupocycloporus) innominatus. These names likewise were first published in the paper quoted. The drawings were made by Miss Violet Dandridge. Tribe Brachyura. Subtribe Oxystomata. Family Dorippidæ. Dorippe dorsipes (Linnæus). Dorippe dorsipes Alcock, LXV, 277. 189t). Between Koh Mesan and Cap Liant, 9 fath.; II. 4; 1 juv. Koh Kam, 5 fath., gravel; II. 6; 1 juv. Koh Kahdal, 5 8 fath., sandy mud; II. 16 and III. 4; 1 juv. North side of Koh Mesan, 10—15 fath., stones, shells; II; 1 juv. Tung Kaben, 6 fath., sand, mud, phanerogams; II. 22; 1?. Koh Lan, 30 fath., mud; III. 2; 1 juv. Koh Kram, 30 fath.; III. 2 and 21; 1 juv. In the adults that I have examined, the carapace of both sexes is broader than long. In young specimens the eyes project laterally beyond the external spine of the orbit. Dorippe facchino (Herbst). Dorippe facchino Alcock, LXV, 278, 1896. Coast of Lem Ngob, 0—1 fath., stones and sand; XII;1?. Koh Kahdat, 8—10 fath., mud; I. 27; 1?. Koh Kahdat, 5—8 fath., sandy mud; II. 16 and III. 4; 3 ? ovigerous. Sound at Koh Chang, 3—5 fath., soft clay; 1900; 1 juv., soft shell. Dorippe astuta Fabricius. Dorippe astuta Alcock, LXV, 280, 189G. Mouth of the river, Paknam-wen, in Chinamen's tow-nets; I. 30; 1 d*. Koh Chik; II. 2; 1 $ ovigerous. Koh Chang, near the Station, low water; III. 10; 1 juv.; crept about with a large leaf over it. The third segment of the male abdomen has a blunt transverse ridge which is bilobed. Family Leucosiidæ. Subfamily LeucosUnæ. Oreophorus rugosus Stimpson. Oreoptiorus rugosus Stlmpson, Smithson. Misc. Coll., XLIX, 159, pL XIX, fig. 6. (> a, 1907. Koh Kam, 5 fath., gravel; II. 6; 1 Ç immature. 306 6 Tlos muriger Adams and White. Tlos muliger Adams and Whitk, Zool. Samarang, Crust., 58, pi. XIII, fig. 2, 1848. N. of Koli Kut, 10 fath.; I. 23; 1 c?. Koli Cliuen, 30 fath., sliell bottom; II; 1 Ç juv. 6 miles East of Cap Liant, 9 fath., shell bottom; II. 1; 1?. Nursia lar (Fabricius). Parthenope lar Faiiricius, Entora. Syst., Suppl., 354, 1798. Niir.iia hardwickii Leach, Alcock, LXV, 181, 1896. Singapore, 2—3 fath.; XII. 4; IJ" 1 ?. Between Koh Kut and Koh Kahdat, 10 fath., shell bottom; I. 10; 2 c? 3 ?. North of Koh Kul, 10 fath.; I. 23; 1 ?. North of Koh Chuen, 15 fath., mud, shells; II. 5; 1 Ç juv. The Gulf at Rayong, 7—10 fath., sand, mud, shells; II. 8; 1 d" 1 ?. North of Koh Kut, 15 fath.; III. 4; 1 Ç ovigerous. Koh Lan, 30 fath., mud; III. 2; 1 Ç juv. Between Koh Chuen and Koh Chang, 15 fath., mud; III. 3; 1 Ç immature. The species "Parthenope Lar Fabricius" has remained till now neglected, its author having classified it according to its general appearance without reference to the mouth parts. The original description is as follows: — "P. thorace inaequali quadridentafo: margine spinoso, chelis laeuibus. "Habitat in India Dom. Daldorff. "Corpus paruum obouatum. Rostrum truncatum, vix exsertum. Thorax in- aequalis dentibus duobus in medio duobusque in linea dorsali postice eleuatis, acutis. Spinae marginalis utrinquetris planae, acutae : intermedia longiore. Chelae longlssimae at omnino laeues." The type specimen is in the Museum at Copenhagen. Milne Edwards had doubts as to the assignment of the species, for he says: — ' "Si le Lambre lar. {Parthenope lar. Fabr. Supp. p. 354) appartient réellement à la tribu des Parthénopiens, il paraît devoir se ranger parmi les Lambres, et il se distinguerait facilement de toutes les autres espèces par ses pinces qui sont tout-à-fait lisses." Heteronucia mesanensis Rathbun. Heteronucia mesanensis Rathbun, Proc. Biol. Soc. Washington, XXII, 107, 1909. As in the typical species of the genus, H. vesiculosa Alcock (LXV, 177, pi. VIII, fig. 1), the surface is closely set with vesiculous granules. The carapace is one-fourth broader than long, subglobular, very uneven; a narrow triangular area in the middle is bordered by a deep groove and embraces the cardiac and meso- gastric regions, the cardiac region being also separately convex; branchial region nodulous and tuberculous, the larger protuberances in the anterior half; an incon- spicuous tubercle on the hepatic region. The lateral margin begins with a tubercle at the angle of the buccal cavity, on the pterygostomian region there is a large » Hist. Nat. Crust., I, 358, 1834. 307 obtuse-angled prominence, the anterior margin of which is nearly transverse and in line with the eye when viewed from above; behind it a smaller prominence, from which a row of tubercles curves backward and strongly upward to a point opposite the middle of the cardiac region. Posterior margin slightly convex. Front and orbits together nearly one-half as wide as the carapace; front with a median furrow, edge subtruncate, faintly bidentate, outer angles rounded. Orbit small, orbicular. Outer maxilliped strongly bent near its middle so that the merus of the endognath is nearly at a right angle to the ischium. Abdomen of female with third to sixth seg- ments fused. Chelipeds knobby like the carapace; arm widening a little distally, palm extremely thick near its proximal end, fingers no longer than palm, opening verticallj', curving in- ward, grooved, ridges finely granulate, prehensile edges evenly denticulate and overlapping, the dactylus lying within the pollex, and nearly as wide as the poUex. This species differs from those hitherto described, in lacking conical tubercles on the carapace, and in the palm being as long as the fingers. Dimensions. — Female, length 3-7 mm., width 45 mm. Localities. — Between Ivoh Mesan and Koh Chuen, 15 fath.; II. 6; one ? ovigerous, type. Between the same islands, 30 fath., stones; II. 5; one Ç adult. Fig. 1. Heteroniicia mesanensis, type 9, 4-5 mm. wide: a, chela; b, leg. Ebalia Avoodmasoni Alcock. Plate 1, fig. 17. Ebalia woodmasoni Alcock, LXV, 188, pi. VII, fig. 3, 1896. Koh Kahdat, 1 fath., sandy bottom, sponges, dead corals; I. 11; 2 ? ovig. Koh Kahdat, 4—5 fath., sand, stones, coral; II. 15—18; 1 ? ovig. These specimens agree well with Alcock's description, but not so well with his figure, which represents the front considerably wider. The largest female is 67 mm. long, 67 mm. wide. Nucia tuberculosa A. Milne Edwards. Nticia tuberculosa A. Milne Edwards, Nouv. Arch. Mus. Hist. Nat., X, 44, pi. II, lig. û, 5 a, 1874. Between Koh Mesan and Koh Chuen, 30 fath., stones; II. 5; 1 c? 1 ? immature. Surface of body and limbs closely covered with acute granules or tubercles. Carapace subglobular, slightly hexagonal ; a little broader than long, with the front set off by a furrow. Regions faintly indicated. Front more than one-third width of carapace. Merus of maxillipeds sharply acuminate. Chelipeds not much longer 308 8 than the carapace; palm so swollen as to be subglobular; fingers almost as long as palm, their opposed edges meeting. Dimensions. — Length of c?, 2 mm., width 22 mm. Persephona fugax (Fabricius). Mijra fugax Alcock, LXV, 202, 1896. South of Koh Bidang, 9 fath., mud, shells; I. 18; 1 ?. North of Koh Kut, 10 fath.; I. 23; 1 c?. 4— 6 miles S. of Koh Samit, 14-18 fath.; II. 1 ; 1 ?. Koh Kahdat, 5—8 fath., sandy mud; II. 16 and III. 4; 2d'- Between Koh Chuen and Koh Chang, 15 fath., mud; III. 3; 1Ç with Rhizocephalid parasite in abdomen. Persephona pentacantha (Alcock). Mi/ra pentacantha Alcock, LXV, 204, 1896. Singapore, 2—3 fath.; XII. 4; 1 Ç juv. Koh Kahdat, 5—8 fath., sandj' mud; II. 16 and III, 4; 1 Ç mature. Tung Kaben, 6 fath., sand, mud, phanerogams; II. 22; 1 $ immature. The measurements of these 3 females are as follows: — Singapore, length 9'8 mm., without spine 8 mm., width 78 mm. Koh Kahdat, length 171 mm., with- out spine 14-9 mm., width 137 mm. Tung Kaben, length 219 mm., without spine 19 mm., width 171 mm. The series indicates that the species is distinct from P. fugax. The two smaller females have the characters given by Alcock. The largest one, not adult, difi"ers from the smaller ones in being less rough, in having the spinule of the postero- lateral margin and those of the antero-lateral margin reduced to large granules as in adult fiigo.v. This species differs from P. fugax in lacking the fringe of hair along the inner pari of the apposed edges of the external maxillipeds. Persephona affinis (Bell). Myra affinis Ai.cock, LXV, 205, 1896. Koh Kam, 5 fath., gravel; II. 6; 1 ? juv. Between Koh Mesan and Koh Chuen, 15 fath., stones; II. 6; 1 c?. Between Koh Rial and Koh Mesan, 3—5 fath., sand, algæ; II. 7; 1 ? juv. Gulf of Rayong, 7-10 fath., sand, mud, shells; II. 8; 1 c? 2 ? juv. Koh Chuen, 30 fath., shell bottom; II; 2c? 1 ? juv., 1$ ovig. Koh Kram, 30 fath.; III. 2 and 21; IJ". The only adult '6 mm. wide; b, chela of same; c, cliela of Ç, ; 7-1 mm. wide; d, maxillipeds; e, abdomen of cf. Subfamily Xenophthalmlnæ. Xenophthalmus pinnotheroides White. Xenophthalmiis pinnoteroides Alcock, LXIX, 332, 1900. Between Koh Kahdat and Koh Kut, 6 falh., sandy clay; I. 9; 1 ?. North of Koh Kut, 10 fath.; I. 23; 1 c? 1 ? 1 juv. These specimens are all smaller than that figured by White (Ann. Mag. Nat. Hist., XVIII, pi. II, fig. 2, 1846, and Zool. Samarang, Crust., pi. XII, fig. 3, 1848), the largest, a female from Koh Kut, measuring 75 mm. wide. The legs are slenderer than represented by White, but probably as in the species below, X. obscurus, the legs are stouter in the adult than in the young. Carapace and legs pubescent. Chelipeds of male, while not much longer than in the female are considerably more enlarged, the chelæ suboval margined above and below. The propodus of the first leg is as broad as long. Xenophthalmus obscurus Henderson. Plate II, fig. 13. Xenophthalmus obscurus Ai.cocK, LXIX, 333, 1900. The Sound at Koh Chang, 3 — 5 fath., soft clay bottom ; XII. 24 to I. 6; 13 J" 20? (2 ovig.) 4 juv. West coast of Koh Chang, a little north of Fig. 23. Xenophihalmus obscurus, Koh Kut, d, ill mm. wide: *'^^ small islands, 10 fath., a, anterior half; b, antenna; c, chela; d, ma.\illipeds; e, abdomen, mud bottom, dead shells; I. 39 339 16; 1 c? 2?. West coast of Koh Kong, 10—15 fath.; I. 24; 1 c?. OfY Koh Kut, 6fath.; I. 26 ; 2 c? 1 ?. In these specimens the ischium and merus of the outer maxillipeds are grooved near the outer border, which is contrary to Alcock's description. I should be dis- posed to consider the Siamese specimens a separate species, did not the shading of the maxillipeds in Henderson's figure (pi. XXXVI, fig. 19, Trans. Linn. Soc. London, Zool. (2), V, 1893) suggest a groove along the outer edge. In our specimens also, the low branchial ridges are connected by a ridge across the cardiac region. In this species the propodus of the first leg is distinctly longer than broad. Subfamily Asthenognathinæ. Asthenognathus hexagonum Rathbun. Plate II, fig. 14. Asthenognathus hexagonum Rathbun, Proc. Biol. .Soc. Washington, XXII, 111, 1909. Carapace I'/a times as wide as long, strongly hexagonal; the posterior margin very little longer than the anterior, or fronto-orbital; antero-lateral and postero- lateral margins subequal. Surface little convex, pubescent and finely punctate, medial furrows deep. Front about ^/s as wide as carapace, advanced beyond the orbits, sides oblique, lower edge straight. Orbits transverse, eyestalks tapering to the black corneae. The granulate anterior and antero- lateral margin is continued part way on the postero- lateral margin. A small part of the carapace behind the lateral angle is strongly deflexed, the true angle being just above the base of the second leg. Posterior margin strongly rimmed. The antennules are folded in deep fossettes. The infra-orbital ridge is strong and shaip. Buccal cavity arcuate in front, not nearly filled by the narrow outer maxillipeds. Ischium and merus of endognath subequal in length, ischium a little wider; segments of palpus end to end. Chelipeds of female feeble, little longer Fig. 2i. Astiienogathus hexagonum, than carapace, almost smooth, fingers longer than palm, 'J'P^ 9- ^'^ ■"'"• ^''J'^- "- anterior J , , ... , , ,, ... border; b, chela: c, buccal cavity, acute, dactylus witli a sharp upper edge, pollex with a smooth ridge outside. Second leg longest, about twice as long as carapace, stout; third subequal to it; first much smaller; fourth most feeble, reaching little beyond merus of preceding pair. Male unknown. Length of ovigerous female 5-6 mm., width 78 mm., fronto-orbital width 43 mm., width of front along lower edge 17 mm. Type locality — North of Koh Kong, 8 fath., mud bottom; 1. 23; 2 c? (1 ovig., type). This species is very closely related to the type species, A. inœquipes Stimpson (Smithson. Misc. Coll., XLIX, 140, pi. XIV, fig. 1, 1907). Chelipeds and legs similar 340 40 in the two species, but the carapace in A. inœquipes is much broader beliind, so that it appears less hexagonal; the posterior margin is 1-5 times as great as the distance across front and orbits in iiue(iinpes; it is just equal to that distance in hexagonuin. In A. japonic a (Ortmann) (= Tritodynamia japonic a Ortmann, Zool. Jahrb., Syst., VU, 693, pi. XXIII, fig. 5, 1894), the front is arcuate, and the second leg is much longer than the third. Chasmocarcinops gelasimoides Alcock. Plate 1, fig. 10; Plate II, fig. 12. Chasmocarcinops gelasimoides Alcock, LXIX, 334, 1900; Illus. Zool. liivcstigiilor, Crust., pt. X, pi. LXIl, figs. 2 and 3, 1902. Between Koh Kahdat and Koh Kut, 0 fath., sandy clay; 1.9; 1 c? 3? (1 ovig.). South of Koh Bidang, 9 fath., mud, shells; I. 18; 1?. North of Koh Kut, 10 fath.; I. 23; 1 c?. 15 miles west of Koh Kut, 30 fath. (s. m.); I. 28; 1 c?. South of Koh Kut, 17 — 20 fath., mud (large seine); I. 28; 8 c? 6 Ç 1 juv.; one male was in shell of living Amussium pleuronectes Linnæus. 12 miles east of Koh Mak, 20 fath., large seine; I. 28; 2 c? 1 ?• 10—12 miles west of Koh Chang, 20 fath., mud; I. 29; 7 c? 2 ?. 20 miles south of Koh Samit, 20 fath., mud; I. 31;.l J". 35 miles west of Koh Chang, 30 fath., clay; I. 31; 1? ovig. 4—6 miles south of Koh Samit, 14—18 fath. ; II. 1 ; 3 c? 3 ?. 2 miles south of Koh Tulu, 10 fath., sandy mud, shells; II. 9; 1 c?. Family Gonoplacidæ. Subfamily Carcinoplacinæ. Eucrate crenata de Haan. Eiicrate crenata Alcock, LXIX, 300, 1900. 15 miles E. of Koh Chuen, 10 fath., shell bottom; II. 2 ; 1 ? juv. Koh Chuen, 30 fath., shell bottom; II; 1 c? juv. 2$ juv. Litocheira setosa (A. Milne Edwards). Litocheira setosa Ai.cock, LXIX, 315, 1900. 15 miles E. of Koh Chuen, 10 fath., shell bottom; II. 2; 1 juv. A small specimen 26 mm. long and 37 mm. wide, in which the second lateral tooth is acutely pointed. Litocheira cristata Rathbun. Litocheira cristata Rathbun, Pioc. IJiol. Soc. Washington, XXII, 111, 1909. Carapace flat except anteriorly where it is moderately deflexed. Regions delineated, cardiac region almost quadrilateral. Antero- lateral region granulate. Surface pubescent, and anterior border of carapace and of chelipeds and legs fringed 41 341 with lony hair. Front deflexed below the fringe, its lobes oblique and sinuous, a V-shaped median notch. The orbits have a notch above and below the outer angle, and a smaller notch near the middle of the upper margin. Of the 4 lateral teeth, Fig. 25. Litocheira cristata, type 9, 7-7 mm. wide: a, dorsal view; b, deflexed margin of front. the first is truncate and fused with the orbital angle, the second is subacute with its outer margin truncate, the third prominent, triangular, the fourth small, acute. Chelipeds of Ç equal. The arm has a thin crest above, forming a tooth near the end of the segment, and a transverse subdistal ridge on the outer surface. Wrist eroded , a blunt ridge along the inner edge, and on a higher plane than the inner tooth. The chelæ are granulate, fingers long and cylindrical, brown in the terminal ^/s. Second pair of legs longest, about twice as long as the carapace. The merus of the first three pairs has a thin smooth crest on its anterior margin, of the fourth pair on its posterior margin. Length of Ç 55 mm., width 77 mm., fronto- orbital width 5 mm., frontal width 28 mm. 15 miles E. of Koh Chuen, 10 fath., shell bottom; II. 2; 1 ?. 6 miles E. of Cap Liant, 9 fath., shell bottom; II. 7 ; 1 ?. 2 miles S. of Koh Tulu, 10 fath., sandy mud, shells; II. 9; 1 Ç type. This species is near Pilumnoplax ciliata Stimpson (Proc. Acad. Nat. Sei. Phila., X,- p. 94 [40J, 1858), of which neither a figure nor type specimen exists, but differs in its narrower carapace, triangular third tooth of the side margin, the nondentate upper border of the arm , and in the existence of a crest on the posterior instead of the anterior border of the merus of the last leg. Fig. 26. Litocheira cristata, type 9, 7'7 mm. wide; a, cliela; b, maxilliped. I), li. 11. Vidensli. Selsk. SUr.. 7. Ii;ekUc. nalurvUlensk. u({ matlieni. AW V. 4. 44 342 42 Heteroplax dentata Slimpson. Heteroplax dentata Stimpson, Smithson. Misc. Coll., XI>IX, 94, 1907. Koh Kahdat, 5—8 fath., sandy mud; II. 10 and III. 4; 1 J" 1 ?. 2 miles S. of Koh Tulu, 10 fath., sandy mud, shells; II. 9; 3 ?. Heteroplax transversa Slimpson. Heteroplax transversa Stimpson, Smithson. Misc. Coll., XLIX, 95, 1907. Between Koh Kahdat and Koh Kut, 6 fath., sandy clay; I. 9; 1 c? 1 ?. Gulf of Rayong, 7 — 10 fath., sand, mud, shells; II. 8; 1 d*. 2 miles S. of Koh Tulu, 10 fath., sandy mud; II. 9; 1 Ç juv. Subfamily Rhizoplnæ. Ceratoplax ciliata Stimpson. Ceratoplax ciliata Alcock, LXIX, .320, 1900. Gulf of Rayong, 7—10 fath., sand, mud, shells; II. 8; Id*. Koh Kahdat, 4—5 fath., sand, stones, coral; II. 15 — 18; 1 c?. Ceratoplax hispida Alcock. Ceratoplax /iispida Alcock, LXIX, 321, 1900. Illus. Zool. Investigator, Crust., pt. X, iil. LXI, fig. 4, 1902. Gulf of Rayong, 7 — 10 fath., sand, mud, shells; II. 8; 1 Ç. 2 miles south of Koh Tulu, 10 fath., sandy mud, shells; II. 9; 2 ? (1 ovig.). The specimens are all small, about 29 mm. long x 3 9 mm. wide. Mertonia lanka Laurie. Plate II, fig. 4. Mertonia lanka Laurie, Report Ceylon Pearl Oj'ster Fisheries, pt. V, Suppl. Rept No. XL., p. 424, pi. I, fig. 11, 11 a-c, 1906. Between Koh Mesan and Cap Liant, 9 fath.; II. 4; 1 Ç ovigerous. Length 39 mm.; width 53 mm. Second leg similar to the third, but slightly longer, the additional length being in the dactyl. The fourth leg is broader than the second and third, ils merus and dactyl shorter, but its coxa and ischium longer than in those legs. The markings on the wrist and hand resemble large flat squamæ. Rhizopa gracilipes Stimpson. Rhizopa gracilipes Stimpson, Proc. Acad. Nat. Sei. Phila., X. 95 [41], 1858. cf. Alcock, LXIX. 322, 1900. Sound at Koh Chang, 3—5 fath., soft clay bottom; XII. 24—1. 6; 23 c? 30 ? (1 ovig., 3 with Rhizocephalids). S. of Koh Bidang, 9 fath., mud, shells; I. 18; 1 Ç. S. of Koh Mak, 5—6 fath.; II. 17; 3 juv. Off Koh Kut, 6 fath.; I. 26; 1 d". 43 343 Carapace about -'/i as long as broad, poslero-lateral borders slightly convergent posteriorly. Regions fairly well marked, cervical suture deep, cardiac region swollen. Surface obscurely granulate, especially toward the lateral margins. Carapace and legs covered with a very short pubescence, with marginal fringes of hair. Antero-lateral margin granu- late and acute as far as the widest portion of the carapace and marked by two obscure notches. Fronto-orbital distance over '/:; width of carapace, front */4 width of carapace, grooved in the middle line, faintly bilobed. Orbits piriform; eyes small, black. Buccal cavern increasing in breadth from behind forwards; merus of maxillipeds with antero-lateral angle produced and rounded; exognath of moderate width. Chelipeds heavy, especially the chelæ, and nearly Fig. 21 . lihizopa giacilipes, smooth, except for marginal hairs. Arm projecting little Koh Chang, c?, y-7 mm. wide: beyond the carapace, with a subterminal tooth above. Wrist granulous at the inner angle, armed with a sharp tooth. Chelæ smooth and shining, with a granulate marginal line above and below; laiger palm as high as its superior length, and with a prominent tooth on the outer side projecting over the dactylus, which has a basal tooth larger than the others. Third pair of legs over 2'/3 x length of carapace. Dimensions. — c?, length 7 mm., width 97 mm. The merus of the outer maxillipeds is much more produced at the anlero- external angle than in Typhlocarcinus Stimpson. Typhlocarcinus villosus Stimpson. Typhlocarcinus villosus Alcock, LXIX, 322, 1900. 20 miles ESE. of Koh Samit, 13 — 14fath., sandy mud, shells; II. 2; 2 ?. 15 miles E. of Koh Chuen, 10 fath., shell bottom; II. Fig. 28. Maxiliiped 2; 2 ? (1 ovig.). Gulf of Rayong, 7-10 fath., sand, mud, shells; oi^JslTliohChuZ, 11. 8: 1 c? 1 ?• 2 miles S. of Koh Tulu, 10 fath., sandy mud, shells; 9,8-9mm. wide. ' II. 9 , 2 c? 5 ?. N. of Koh Kul, 10 fath.; I. 23; 1 d*. a, abdomen ; b, chela ; c, ma.villiped. Typhlocarcinus nudus Stimpson. Plate I, fig. Ü. Typhlocarcinus nudus Alcock, LXIX, 322, 1900. Singapore, 2—3 fath.; XII. 4; Id* 2?. Between Koh Kahdat and Koh Kut, 6 fath., sandy clay; I. 9; Sc? 1 ?. S. of Koh Bidang, 9 fath., mud, shells; I. 18; 1 J" 1 ?. W. of Koh Kong, 10-15 fath.; I. 24; 1 c? 1 ?. 12 miles E. of Koh Mak, 20 fath. (large seine); I. 28; 1 d*. 7 miles NW. to W. from Koh si Chang, 10 fath., mud; 11.24; I?. N. of Koh Kut, 10 fath.; I. 23; 1 juv. Fig. 29. Maxiliiped of Typhlocarcinus nudus, Singapore, 9> 65 mm. wide. 44* 344 44 Scalopidia spinosipes Stimpson. Plate II, fig. 2. Scalopidia spinosipes Alcock, LXIX, 325, 1900. Off Koh Kut, 6 fath.: I. 26; 1? juv. S. of Koh Kut, 17—20 fath., mud (large seine); I. 28; 2 d* 2 ?. 20 miles S. of Koh Samit, 20 fath., mud; 1. 31; 3 c? 6 ? (1 evig.). 35 miles W. of Koh Chang, 30 fath., clay; I. 31 ; 1 ? juv. The largest c? (Koh Samit) is 14 mm. long, 195 mm. wide. The third, fourth and fifth segments of the c? abdomen are incompletely fused. Camatopsis rubida Alcock and Anderson. Camatopsis rubida Alcock, LXIX, 329, 1900. 12 miles E. of Koh Mak, 20 fath., large seine; I. 28; 1 d. Megæsthesius Rathbun. Megœsthesius Rathbun, Proc. Biol. Soc. Wasliington, XXII, 112, 1909. Allied to Camatopsis Alcock (Investigator Deep-Sea Brachyura, p. 75, 1899) but differs in having the eyes unpigmented, the movable part of the antennules not only excluded from the fossettes, but immensely stout, the buccal cavern anteriorly narrowed and arcuate, the outer maxillipeds touching each other, the ischium as broad as long and broader than the merus, which is subtriangular and bears the palp at its summit, exognath short and narrow. Megæsthesius sagedae Rathbun. Plate II, fig. 5. Megœstliesius sagedœ Rathbun, Proc. Biol. Soc. Washington, XXII, 112, 1909. Carapace pentagona], the long postero-lateral borders parallel, forming distinct angles with the short antero- lateral bor- ders which are in line with the orbits. Surface nearly naked, rough with sharp granules, which on the borders become spi- nules; very convex fore and aft, level from side to side. Front about one- fifth as wide as carapace, bilobed by a deep groove, lobes arcuate. Eyestalks rough like the carapace, not pigmented. Epistome small. Pterygostomian region swollen. Fig. 30. Megœsthesius sagedœ, type d', 2-7 mm. wide. 45 345 Antennules immensely slout, the last two segments of the peduncle wider than the lobes of the front, the flagellum fringed with long hair which reaches to the sternum when the antennules are applied to the ventral surface. Antennae slender, crowded by the antennules away from the front. Chelipeds of the c? shorter and not much stouter than the legs, pubescent, rough; wrist suboval, bearing a spinule at the inner angle, fingers cylindrical, longer than the palm, the lower margin of which is spinulous. Legs long and narrow, margins spinulous. Abdomen of c? widest at the third segment; third to fifth segments fused. Length of J' 27 mm., width 2"7 mm., fronto-orbital width 1-8 mm., width of front n o fig- 31. Megœsthesius sagedæ, U'D mm. ,„ , n.T 1 type o, 2'7 mm. wide, antero- Singapore, 2—3 fath.; XII. 4; 1 c? type. ventral view. Subfamily Typhlocarcinopsinæ Rathbun. The first segment of the male abdomen covers the whole space between the last pair of legs. Otherwise, as in the Rhizopinæ, to which it bears the same relation that theCarcinoplacinæ does to thePrionoplacinæ. The type of the subfamily is Typhlocarcinops Rathbun. Tgphlocarcinops Rathbun, Proc. Biol. Soc. Wasliington, XXII, 112, 1909. Differs from Typhlocarcinus Stimpson (cf. Alcock, LXIX. 321, 1900), chiefly in having the first segment of the c? abdomen very broad, covering the whole width of the sternum, and transversely grooved. Remainder of abdomen narrow. Type and only species: Fig. 32. Typhlocarcinops canaliculata, Koh Mak, c?, 34 mm. wide; a, carapace; 6, abdomen; c, chela; d, maxilliped. Typhlocarcinops canaliculata Rathbun. Plate II, fig. 16. Typhlocarcinops canaliculata Rathbun, Proc. Biol. Soc. Washington, XXII, 112, 1909. Carapace, chelipeds and legs sparingly hairy on the margins. Carapace three-fourths as long as wide, widest posteriorly, meso- gastric region faintly marked. Lateral mar- gins granulate, entire. Fronto-orbital width about three-fifths of the total width of the carapace; nearly half of the distance is occupied by the front. The latter widens anteriorly, is strongly 346 46 deflexed, medially sulcate, lower margin arcuate, faintly emarginate in the middle. Orbits almost circular; eyes faintly pigmented. Buccal cavity with sides parallel. Antero-external angle of merus of outer maxillipeds well marked but not produced. Chelipeds about one and one-half limes as long as carapace. Inner angle of wrist not prominent. Palm pubescent and on the lower half finely granulous. Second and third legs subequal. Second pair longest, about twice as long as carapace. Neither of the two specimens is adult, and the segments of the abdomen are not clearly marked; save for the broad first segment, the abdomen is very narrow, being at the third segment less than one-third the width of the sternum. Length of type c? 2-7 mm., width 3-6 mm., fronto-orbilal width 2 mm., frontal width 09 mm. Between Koh Mesan and Cap Liant, 5—8 fath., sand, stones; H. 7 ; 1 c? type. S. of Koh Mak, 5—6 fath.; IL 17; 1 c?. Subfamily Hexapodinæ. Thaumastoplax orientalis Rathbun. Plate II, iig. 1. Thaumastoplax orientalis Kathbun, Proc. Hiol. Soc. Washington, XXII, 113, 190». Carapace one and two-fifths times as broad as long; longitudinally very convex, transversely nearly level; naked and coarsely punctate, a faint H-shaped depression at the middle. Lateral borders marked by a raised line. The fronto- orbital distance, while about two-fifths as great as the extreme width of the carapace, occupies only a little more than half of the anterior margin, the so-called antero-lateral margin being angularly arcuate, its anterior portion transverse, a slight notch on the outer portion, postero-lateral margins sub-parallel ; posterior margin convex, postero-lateral angle obliquely cut off above the insertion of the third leg. Front one-fourth the width of the carapace, posteriorly constricted, anterior margin concave, except for a broad shallow median tooth. Orbits transversely oval, appearing marginal in a dorsal view. Antennæ in the orbital hiatus; flagella three times as long as the major diameter of the orbit. Epistome obsolete in the middle , narrow at the sides. Fig. 33. Thaumastoplax orientalis, type cf, 126 mm. wide: a, abdomen; jjuccal cavity much broader than long, anteriorly arcuate, sides 6, abdominal appendages. .-ij- i,^, -n-ji -iin anteriorly divergent. Outer maxillipeds large , especially the palpus, which occupies the length of the cavity; a hiatus exists between the palpus and the ischium; there is a transverse fringe of hair across the middle of the maxillipeds, as well as a marginal fringe on the last two joints. Anterior half of 47 347 the niaxillipeds nearly vertical. The maxilliped is shaped much as in the type species T. anomalipes Miers (Ann. Mag. Nat. Hist. (5), VIII, pi. XIV, fig. 2 b, 1881), but the propodus is as wide as long. Chelipeds short, equal; merus with a superior subterniinal spine; wrist smooth and bare except near the inner angle, where it is sharply granulate and hairy. Palms higher than long, granulate, granules arranged only partly in rows, lower edge bordered by a row of prominent sharp tubercles continued half way on the thumb. Dactylus spinulous above. Fingers narrowly gaping. Second leg much larger than the first and third , which are subequal ; upper margin of merus of second leg spinulous. Margins of chelipeds and legs and also the pterygostomian regions long-hairy. Margins of sternal segments and of abdomen furrj^. Third and fourth segments of c? abdomen fused, and also the fifth and sixth. The terminal segment projects between the tips of the dactyli of the two outer niaxillipeds. The appendages of the first segment are much longer than the abdomen but do not project beyond it; their extremities being doubly recurved, forming together a figure 8. Length of c? 9 mm., width 12-6 mm., width across front and orbits 5 mm., greatest width of front 28 mm. Type locality. — N. of Koh Kut, 10 fath.; I. 23: 1 d*. This species differs from T. anomalipes Miers (Op. cit., p. 261, pi. XIV, fig. 2) in its narrower carapace, shorter, stouter claws and smaller third leg. Thaumastoplax chuenensis Rathbun. Thaumastoplax chuenensis Rathbun, Proc. Biol. Soc. Washington, XXII, 113, 1909. Fig. .34. Thaumastoplax chuenensis, type cf. "l-S mm. wide. Fig. 35. Thaumastoplax chuenensis, type d", 4-8 mm. wide: a, maxilliped; b, chela. Differs from T. orientalis in a little narrower carapace, about one and one-third times as broad as long, with the gastric region sharply outlined, the cardiac region less distinctly so, the branchio-hepatic groove faint; antero-lateral margin less angled; fronto-orbital distance greater, one-half width of carapace; front widest at its lower 348 48 margin where il is nearly one-third as wide as carapace; epistome complete though narrow; legs narrower than in T. orientalis. Founded on a young male, in which only the last segment of the cJ" abdomen is distinctly separated. Length 35 mm., width 48 mm., width across front and orbits 25 mm., greatest width of front 15 mm. Type locality. — Koh Chuen, 30 fathoms, shell bottom; II; 1 d". Lambdophallus anfractus Rathbun. Lambdophallus anfractus Hathbun, Pioc. 3iol. Soc. Washington, XXU, 113, 1909. Carapace subquadrilateral with the anterior angles rounded, one-half broader than long, convex fore and aft, anteriorly deflexed, slightly convex from side to side, gastric and cardiac regions well defined, surface shorl-pubescent and finely granulate and punctate. At the postero- lateral corners there is a small but very well marked lobe. Front nearly vertically deflexed, about one-fifth as broad as the greatest breadth of the carapace, subtruncate with the outer angles rounded , and with a median groove which bilobes the front in a dorsal view. Orbit oblong-oval, about as wide as each lobe of the front and inclined downward and outward in a front view. Eyes almost immovable, pigmented. Antennules transverse, septum narrow. Antennæ more than twice as long as the major diameter of the orbit. Epistome well defined. The buccal cavity narrows anteriorly. The inner margin of the ischium-merus is very convex, so that the space between the ischium joints is very nearly filled by the palpi, the propodal joint of which is less enlarged than in the type species L. sexpes (cf. pi. LXII, fig. la. Illus. Zool. Investigator, Crust., pt. X). There are several fine oblique raised lines near the buccal cavity. Chelipeds unequal in the c?, equal in the Ç, the larger one in the J" one and one-half times as long as the carapace, finely granulate, fingers meeting only at tip, a low molariform tooth at base of dactyl. Legs tomentose and granulate, third pair longest, a little more than twice as long as carapace, first pair shortest and narrowest, merus joints longitudinally furrowed. Sternum finely granular; in the first segment is a transverse sinuous trench, to hold the curved and projecting extremities of the abdominal appendages. The narrow c? abdomen has the first two segments short, no suture lines visible between the third, fourth and fifth segments, sixth segment nearly as long Fig. 36. Lambdophallus anfractus, type (S, 7'2 mm. wide: a, sternum and abdomen; b, abdominal appendages; c, maxilliped. 49 349 as wide and widest near the middle, seventh segment subtiiangular with convex sides. ? abdomen subovate, widest at the sinus between third and fourth segments, all segments distinct. Length of tj'pe d* 47 mm., width 7-3 mm. Record of specimens. — W. coast of Koh Chang, a little N. of the small islands, 10 fath., mud bottom, dead shells; I. 16; 1Ç ovig. Koh Chang, about 1 fath., coral; I. 17; 1?. N. of Koh Kong, 8 fath., mud; I. 23; 2?. Off Koh Kut, 6 fath.; I. 26; 2 J* (1 type) 5 Ç (2 ovig.). 15 miles W. of Koh Kut, 30 fath., on Chcetodiadema granulatuni Mortensen; 1 c?. The Sound at Koh Chang, 3 — 5 fath., soft clay bottom ; 1 c?, 1 Ç. Differs from the type species, L. sexpes Alcock (Jour. Asiat. Soc. Bengal, LXIX, p. 330, 1900) in its narrower carapace, and the different shape of the maxillipeds, abdomen and sternal trench. This species has a suspicious resemblance to Hexapns sexpes de Man (Arch, f. Naturg., LIII, 1, p. 322, pi. XIII, fig. 3, 1887), but the author does not mention a sternal trench. I doubt if the species represented b^' him is the same as H. sexpes de Haan or H. sexpes A. Milne Edwards which appear also to be distinct from each other. The type of Cancer sexpes Fabricius (Entomol. Syst., Suppl. p. 344, 1798) is not extant, so that the specific name can perhaps not well be retained for de Haan's species. a (?)Hexaplax, sp. Tung Kaben, 6 fath., sand, mud, phanerogams; II. 22; 1 c?, young and soft shell, about 18 mm. wide. This specimen has the form of carapace and front of H. megalops Doflein', also large reniform black eyes set in orbits similar to those of that Fig. 37. Hexaplax, sp., d, is mm. species. The specimen is devoid of chelipeds and ^^'^e: a, body, showing front , J • • , 11, ,1 1 .11.., flattened out, instead of curving legs and is m too bad shape to be described with , j ■ ■. » i ■»■ o r downward m its natural position; accuracy. fc, ma.xilliped. Family Xanthidæ. Subfamily Xanthinæ. Cymo melanodactylus de Haan. Cijmo melanodactylus Alcock, LXVII, 174, 1898. Koh Kahdat, coral and coral blocks, 1 fath.; I— II; 2c?, 1 ?. 1 Brachyura "Valdivia", p. 122, pi. XXXI. fig. 3— 4, pi. I, fig. 7, 1904. D. K. I). VIdensk. Selsk. Skr.. 7. Række, naturvidensk. og mathem. Afd. V. 4. 45 350 50 Xantho scaberrimus Walker. Xantho (Lophoxanthus) scaberrimus Alcock, LXVII, IKi, 1898. Koh Chuen, 30 fath., shell bottom; II; 1 juv., 73 mm. in width. Unlike the adult, the fronto-orbital distance is more than half as great as the width of the carapace; the legs are longer and narrower than in the adult. Leptodius exaratus (Milne Edwards). Xantho (Leptodius) exaratus Alcock, LXVII, 118, 1898. Coast of Lem Ngob, 0 1 fath., stones and sand; XII; 1 c?. Koh Chik, rocky coast; I. 30; IJ" 2 Ç (1 ovig.). Koh Chang, 1 fath., coral; I-III; Id*. Leptodius sanguineus (Milne Edwards). Xantho (Leptodius) sanguineus Alcock, LXVII, 119, 1898. Koh Kahdat, 1 fath., coral and coral blocks; I — II; 1$. Koh Chang, 1 fath., coral ; I— III ; 1 ?. These specimens are the nodosus form, figured by Dana (pi. XI, figs. 14a — g, Crusl. U. S. Expl. Exped.) in which the tips of the lateral teeth are much thickened and strongly produced. Cycloxanthops lineatus (A. Milne Edwards). Plate II, fig. 15. Ctjcloxanthus lineatus Alcock, LXVII, 124, 1898. Koh Chuen, 30 fath., shell bottom; I. 2; 1? juv. Between Koh Kut and Koh Kahdat, 10 fath., shell bottom; I. 10; 1 ?. Between Koh Mesan and Cap Liant, 9 fath.; II. 4; 1 c?. N. of Koh Chuen, 15 fath., mud, shells; II. 5; 3 c? 5 ?. Koh Kam, 5 fath., gravel; II. 6; 1 J" 1 ? ovig. Gulf of Bayong, 7 — 10 fath., sand, mud, shells; II. 8; 2^. Koh Chuen, 30 fath., shell bottom; II; 1 c? 1 ?• Koh Lan, 30 fath., mud; III. 2; 2 juv. The specimens are all smaller than the type , the largest one (d*, Koh Kam) measuring 55 mm. long and 73 mm. wide; the outer angle of the orbit is more prominent than in larger specimens, forming a little blunt tooth similar to the next tooth on the antero-lateral margin. Actæa nodulosa White. Aciœa nodulosa Alcock, LXVII, 148, 1898. Koh Chuen, 30 fath., shell bottom, II; 1?. Koh Kram, 30 fath.; III. 2 and 21; 2 c? juv. Actæa savignyi (Milne Edwards). Actæa granulala Alcock, LXVII, 151, 1898. Not Cancer granulatus Linnæus, 1758. Between Koh Kut and Koh Kahdat, 10 fath., shell bottom; I. 10; 1? juv. 15 miles E. of Koh Chuen, 10 fath., shell bottom; II. 2; 1Ç ovig. Koh Kam, 5 fath., 51 351 gravel; II. 6; 1 J" juv. 1 ? juv. Koh Chuen, 30 fath., shell boltom; II; 2 ? juv. Koh Kram, 30 fath.; III. 2 and 21; 1? juv. Actæa calculosa (Milne Edwards). Aclæii calculosa Alcock, LXVII, 152, 1898. Between Koh Mesan and Cap Liant, 9 fath.; II. 4; 1 d* 2 Ç juv. Between Koh Mesan and Koh Chuen, 30 fath., stones ; II. 5 ; 1 c?- Between Koh Mesan and Koh Chuen, 38 fath., stones; II. 7; 1 d*. Between Koh Mesan and Cap Liant, 5—8 fath., sand, stones; II. 7; le? 1 juv. Koh Kram, 30 fath.; III. 2 and 21 ; 1 Ç juv. Platypodia granulosa (Rüppell). Lophactœa granulosa Alcock, LXVII, 101, 18i)8. Singapore, coral reef; XII. 5; le?. Atergatis ocyroe (Herbst). Atergatis floridus Alcock, LXVII, 98, 1898. Koh Kahdat, among corals; II. 13; 2c?. Koh Chang, 1 fath., corals; I— III; 1 $ ovig. 4 juv. Atergatis dilatatus de Haan. Atergatis dilatatus Alcock, LXVII, 96, 1898. Koh Chang, 1 fath., corals; I — III; 1 c? 1 juv. Subfamily Carpiliinæ. Chlorodiella niger (Forskål). Clüorodius niger Alcock, LXVII, UiO, 1898. Koh Kahdat, coral and coral blocks, 1 falh. ; I — II; 5 c? 5 Ç (2 ovig.) 4 juv. Koh Chang, coral, 1 fath.; I-^III; 2 c? 1 ?. Carpilodes rugipes (Heller). Actœodes rugipes Heller, S. B. K. Akad. Wiss. Wien, Math.-Naturw. CI., XLIII, 1. Abth., 3.3U, pi. II, fig. ■>(), 18Ü1. Carpiloxanthus rugipes Heller, Reise Novara, Crust., 17, 1865. Carpilodes rugipes A. Milne Edwards, Nouv. Arch. Mus. Hist. Nat., Paris, I, 229, pi. XII, fig. 4, 4 a, 4 b, 1866. Koh Chang, coral, 1 fath.; I- III; 2?. Carpilodes lophopus Alcock. Plate II, fig. 18. Carpilodes lophopus Alcock, LXVII, 84, 1898; Illus. Zool. Investigator, part VII, pi. XXXVI, fig. 2, 1899. 15 miles E. of Koh Chuen, 10 fath., shell bottom ; II. 2 ; 1 ?. Between Koh Mesan and Koh Chuen, 30 fath., stones; II. 5; 1 Ç. North side of Koh Mesan, 10—15 fath., stones, shells; II; 1 c? 1?. Koh Chuen, 30 fath., shell bottom; II; 3?. 45* 352 62 The largest specimen (? between Mesan and Chuen) is 6-5 mm. long and 10'5 mm. wide. All are more distinctly areolated than the one figured by Alcock. The areola IM (of Dana) is distinct; 2 M is longitudinally divided, and there is a triangular areolet in front of the outer half; a square supra-orbital areolet; D and E arc fused; 1 L, 2 L and 3L are fused and eroded; IR and 2R are fused with S; 4L is fused with T; 5L and 6L are each distinct; the transverse groove across the posterior part of the carapace is deep. Hypocolpus haanii Rathbun. Cancer (Xantho) granulatus de Haan, Fauna .Japon., Crust., p. G5, pi. XVIII, fig. 3, 1837. Not Cancer granulatus Linn.i;us, 1758. Hypoccelus granulatus A. Mii,jiE Edwards, Nouv. Arch. Mus. Hist. Nat., Paris, I, 296, pi. XVI, fig. C, G a, 1866. Henderson, Trans. Linn. Soc. London, (2), Zool., V., p. 358, pi. XXXVI, fig. 12, 1893. Hypocolpus haanii Rathbun, Proc. Biol. Soc. Washington, XXII, p. 114, 1909. Koh Kram, 30 fath.; III. 2 and 21 ; 1 c? 1 juv. Subfamily Etlslnæ. Chlorodopsis melanochira A. Milne Edwards. Chlorodopsis melanochira Alcock, LXVII, 168, 1898. Singapore, coral reef; XII. 5; 1 d* 1 juv. Koh Kahdat, 1 fath., sandy bottom, sponges, dead corals; I. 11; 3 J' 1Ç ovig. 3 juv. Koh Kahdat, among algæ; II. 19; 1 c?. Koh Kahdat, 1 fath., coral and coral blocks; I— II; 4 J" 6 Ç 2 juv. Koh Chang, 1 fath., coral; I— III; 7 J* 10 ? (3 ovig.) 18 juv. Halimede de Haan. Halimede de Haan, Fauna Japon., 35, 1835 (fragifer). Andromeda Gistel, Natur. Thierreichs, p. IX, 1848. PoUjcremnus Gerstäcker, Arch. f. Natur., XXII, pt. 1, 120, 1856 (ochtodes). Three species of this genus form a regular series according to the amount of ornamentation. They are as follows: Halimede tyche (Herbst). Cancer tyche Herbst, Naturg. d. Krabben u. Krebse, III, Heft 2, p. 35, pi. LII, fig. 3, 1801, Ostindien. Cancer (Halimede) fragifer de Haan, Fauna Japon., Crust., p. 47, pi. XIII, fig. 4, 1835, Japan. Halimede thurstoni Henderson, Trans. Linn. Soc. London (2), V, p. 360, pi. XXXVI, figs. 13, 14, 1893, Tuticorin. Halimede ochtodes (Herbst). Cancer ochtodes Herbst, Naturg. d. Krabben u. Krebse, I, p. 158, pi. VIII, fig. 54, 1783. Polycremnus ochtodes Alcock, Jour. Asiat. Soc. Bengal, LXVII, p. 135, 1898 and synonymy. 53 353 Polycremnus verrucifer Slinipson, Smithson. Misc. Coll., XLIX, p. 49, pi. VI, fig. 1, 1907 and synonymy. H. tyche has the carapace, wrist and palm covered with raised, flattened and distinctly separated prominences, as shown in de Haan's figures (of fragifer). These prominences are pitted or irregularly grooved. The type of C. tyche is in the Berlin Museum; it is a small specimen 95 mm. long by 11'4 mm. wide, and is undoubtedly the same as H. fragifer. H. thurstoni has similar flattened prominences, but fewer of them; they are restricted to the anlero-lateral and suborbital regions of the carapace, the surface of the wrist, and the upper and proximal half of the palm. H. ochtodes is without flattened prominences, but the antero-lateral protuberances of the carapace are low and rounded, the wrist and supero-proximal surface of the palm are covered with rounded tubercles. P. verrucifer corresponds to the young of H. ochtodes. As these three species present no other differences, it is quite probable that they were derived one from another in the order named, and it would not be surprising if intermediate forms existed. The young (at least of H. thurstoni and H. ochtodes) present greater inequalities of the surface than the old. H. tyche is not represented in the Siam collection, but the other species were taken as follows: Halimede thurstoni Henderson. Plate I, fig. 19. Plate II, fig. 7. Between Koh Kut and Koh Kahdat, 10 fath., shell bottom; I. 10; 1 c? juv. 1 juv. Koh Kam, 5 fath., gravel; II. 6; 1 Ç jnv. 2 juv. Between Koh Mesan and Cap Liant, 5 — 8 fath., sand, stones; II. 7 ; 1 c? juv. Koh Chuen, 30 fath., shell bottom; II; 1 c? juv. 1Ç juv. with Rhizocephalid. Between Koh Rin and Clifl" Rock (N. of Koh Kram), 15 fath.; III. 2; 2 juv. N. of Koh Chuen, 15 fath., mud, shells; II. 5; 1 juv. Halimede ochtodes (Herbst). Plate I, fig. 4. The gulf at Rayong, 7 — 10 fath., sand, mud, shells; II. 8; 1 ? ovig. Koh Kahdat, 4—5 fath., sand, stones, coral; II. 15 — 18; 1? juv. Koh Chuen, 30 fath., shell bottom; II; 1 c? with large Rhizocephalid. Koh Lan, 30 fath., mud; III. 2; 1? juv. In young specimens the lateral projections are more acute than in the adult. Length of ovigerous Ç 31 mm., width 42 6 mm. This species has been recorded at Hong Kong (Stimpson), Singapore (Walker), Penang (Alcock), Madras Coast (Alcock), East India (Herbst), Indian Ocean (AdaiMS and White). 354 54 Fig. 38. Menippe coiwcxa, Koh Kong, d, 1'2'7 mm. wide. Subfamily Menippinæ. Menippe convexa Rathbun. Menippe convexa Kathbun, Bull. U. S. Fish Comm. for 1903, pt. III, 8Ü1, pi. XI, fig. 4, 1906. Fishing-weir at Koh Kong; I. 21; 1 J". Length 97 mm., width 129 mm. Carapace a little narrower than the type Ç, regions slightly better marked, surface showing a close flat granulation , especially in the anterior half, lateral teeth stronger, more acute. Chelipeds more unequal than in the Ç. Fine dots of a dark color on the posterior part of the cara- pace, legs transversely banded. Myomenippe granulosa (A. Milne Edwards). Menippe (Myomenippe) granulosa Ai.cock, LXVII, 179, 1898. Coast of Lem Ngob, 0 — 1 fath., stones and mud; XII; 2 J* 5 Ç lOjuv. Mangrove swamp. Lem Ngob ; XII, 23, 24 and 27 ; 2 c? 2 ?. Koh Chang, stony coast at low water; I; 1 c? 1 juv. Eurycarcinus orientalis A. Milne Edwards. Eurycarcinus orientalis Alcock, LXVll, 210, 1898. Mangrove swamp, Lem Ngob; XII, 23, 24 and 27; 1?. Coast of Lem Ngob, 0 — 1 fath., stones, sand; XII; 4 c? 1 ? 5 juv. Koh Chang, stony coast at low water; I; 1 c? 1 Ç. Coast of Lem Ngob, above low water mark; XII, 28; 2 Ç 8 juv. Gulf of Siam, without special loca- lity; 1 c? 1?. Koh Chang, coral, 1 fath.; I— III; Ic? 4? (1 ovig.) 5 juv. Koh Chang, under stones on coast, extreme low water; I. 12; 1 J* juv. Fig. 39. Eurycarcinus orientalis, Lem Ngob, 9i 13"5 mm. wide. Pilumnus vespertilio (Fabricius). Pilumnus vespertilio Alcock, LXVII, 192, 1898. Singapore, coral reef; XII, 5; 6 d'' 2 ?. Between Koh Mesan and Cap Liant, 5 — 8 fath., sand, stones; II. 7; 1 juv. Koh Chang, 1 fath., coral; I — III; 1 juv. 55 355 Pilumnus longicornis Hilgendoif. Pilumnus longicornis Alcock, LXVll, 193, 1898. Koh Kram, 30 fath.; III. 2 and 21; 1 ? juv. Koh Kahdat, 5-8 fath., sandy mud, II. 16 and III. 4; 1 ? ovig. Gulf at Rayong, 7—10 fath., sand, mud, shells; II. 8; 1 ?. Between Koh Mesan and Koh Chuen, 15 fath., stones; II. 6; 1 juv. Between Koh Mesan and Cap Liant, 5—8 fath., sand, stones; II. 7; 1 juv. These specimens differ from the type in having the greater pari of (he outer surface of the large hand , granulous and hairy ; this may be due to the smaller size of the specimens. Pilumnus andersoni de Man. Pilumnus andersoni Alcock, LXVII, 194, 1898. 15 miles east of Koh Chuen, 10 fath., shell bottom; II. 2; 1 Ç. Koh Chuen, 30 fath., shell bottom; I. 2; 2? 2 juv. Koh Chuen, 30 fath., shell bottom; II ; 1 c? 5? (1 ovig.). Koh Kram, 30 fath.; III. 2 and 21; 6 J* 7$ (2 ovig.) 12 juv. Koh Kahdat, 1 fath., coral, coral blocks; I— II; 2 c? 1 ? ovig. Koh Chang, 1 fath., coral; I— III; 2^* 7? (1 ovig.) 12 juv. The specimens are all small, the largest measuring 4 mm. long, 6 wide. The outer angle of the orbit is inclined to be spiniform, but the spine is very short, not approaching in size the other spines. Pilumnus edamensis de Man. Pilumnus edamensis de Man, Arch. f. Naturg., LIU, 1, p. 302, pi. XI, fig. 5, 1887. Koh Kalidat, 1 fath., coral and coral blocks; I— II; 1 c?- Koh Chang, 1 fath., coral; I— III; 3 Ç. Bay at south end of Koh Chang, among large oysters; III. 14; 1 c?- Pilumnus cærulescens A. Milne Edwards, var. Plate I, fig. 15. Pilumnus cærulescens Alcock, LXVII, 19(i, 1898. Koh Kahdat, 1 fath., sandy bottom, sponges, dead coral; I. 11; 1 c? 2$ (1 ovig.). Koh Kahdat, among algæ; II. 19; 1 d* juv. 1 Ç. Corresponds well to Alcock's description except that the hands are not closely granulate. Pilumnus hirsutus Stimpson. Pilumnus hirsutus Stimpson, Smithson. Misc. Coll., XLIX, ()9, pl. IX, fig. 1, 1907. Cf. Rathbun, Bull. Mus. Comp. Zool., XXXIX, 129, 19(12 Koh Kahdat, 1 fath., sandy bottom, sponges, dead corals; I. 11; 1 Ç 3 juv. Between Koh Mesan and Koh Chuen, 25 fath., shells, II. 5; 1 juv. Koh Kam, 5 fath., gravel; II. 6; 3 c? 3? (1 ovig.). Between Koh Rial and Koh Mesan, 3— 5 fath., algæ; II. 7; 1?. Between Koh Mesan and Cap Liant, 5—8 fath., sand, stones; II. 7; 2c? 1?. Koh Krara, 30 fath.; III. 2 and 21; 2 <^. Twelve miles east of Koh Mak, 20 fath., large seine; I. 28; 1«?. 356 56 A c? from Koh Kram is about the size of Slimpson's type and resembles his figure. The lobes of the front are more rounded and less oblique than in smaller specimens, edge minutely crenulate, and the median emargination shallower. Carapace very convex both ways. The projections of the chelipeds are sharp, spinulous. Besides the short pubescence of the surface there are numerous long hairs. Length of carapace of J", So, width llömm. Pilumnus dorsipes Stimpson. Plate 1, figs. 3 and 9. Pilumnus dorsipes Stimpson, Smithsou. Misc. Coll., XLIX, 70, pi. IX, fig. 3, 3 a, 1907. Koh Kram, 30 fath.; III. 2 and 21; 1? juv. Length 79 mm., width 10'4 mm. Corresponds to Alcock's description fairly well. There is a bunch of subhepatic granules. The surface of the wrist and chela is covered with blunt curved spines. Stimpson's figure shows the legs somewhat shorter, and those of the last two pairs broader. Pilumnus borradailei Rathbun. Plate 1, fig. 8. PUumnus borradailei Rathbun, Proc. Biol. Soc. Washington, XXll, p. 113, 1909. Carapace very flat except anteriorly, about ■'/4 as long as broad, covered with a dense short pubescence, and long hairs, forming a fringe on the anterior border of the carapace and abundant on the chelipeds even to the finger tips and on the legs. When denuded, the regions of the carapace are fairly well marked, the surface is finely punctate, and towards the antero-lateral regions a little granular. Fronto-orbital border '/id of width of carapace, Va of this is occupied by the front , the two lobes of which are very oblique, convex, witli a shallow median emargination, outer angles rectangular, rounded off and scarcely separated from the inner angle of the orbit. The outer of the two superior fissures of the orbit is small, the Fig. 40. Chela inner scarcely discernible ; nolcli below the outer angle broad. (denuded) of Antero-lateral margin crossed by three grooves which form four ,.,.,,, ^, "' shallow lobes with granulated edges, which diminish in size from dailei, Koh Chang, " ° ' <3, 9-4 mm. wide, ^he first to the fourth. Postero-lateral margins slightly converging. Chelipeds stout; merus broader than long; carpus almost smooth except for fine granules along the distal margin ; palms wider than their superior length, surface covered with numerous but not contiguous small pearly granules, which are continued half way along the fingers; only the distal half or less of the fingers is dark-colored. Third pair of legs twice as long as carapace. Legs unarmed. Length of type c? 74 mm., width 10 mm., fronto-orbital width 71 mm., width of front 35 mm. 57 357 Koh Kahdat, 1 falh., coral and coral blocks; I— II; 1 c? 1 ?• Koh Chang, 1 fath., coral; I— III; 2 d* (1 is type). Nearest to P. pilosus Fulton and Grant ', from which it differs in lacking the naked triangular area on the palms, in having the fingers meeting when closed, and in ils greater hairiness (judging from the figures of P. pilosus). Actumnus setifer (de Haan). Actumnus setifer Alcock, LXVII, :202, 1898. Between Koh Mesan and Cap Liant, 5—8 fath., sand, stones; II. 7; 1 Ç. Koh Kahdat, 4—5 fath., sand, stones, coral; II. 15—18; 2 (^ 2 ?. North side of Koh Mcsan, 10—15 fath., stones, shells; II ; 1 J" 1 ?. 15 miles east of Koh Chuen, 10 fath., shell bottom; II. 2; 2? (1 ovig.). Actumnus changensis Rathbun. Actumnus cliangensis Rathbun, Proc. lîiol. Soc. Washington, X.Xll, p. 114, 1909. Surface almost bare, only occasional hairs, both long and short, which in no way disguise the markings. Fig. 41. Actumnus cliangensis, Koh Chang, d", 57 mm. wide. Carapace -/:i as long as broad, regions very slightly indicated, viz., the mesogastric and cardiac; epigastric lobes slightly elevated. Frontal and antero-lateral regions dotted with separated granules; an indistinct line of granules curves inward and forward from the last lateral tooth. Front ';;i as wide as carapace, bilobed, with a median notch, each lobe slightly convex and separated from the orbital angle by a rectangular notch. • Proc. Roy. Soc. Victoiia, XIX (n. s.). p. 7, pi. IV, lig. 1-4, 190G. I). K 1). Viilonsk. Selsk. Skr., 7. licikUc, n;ilurviilensk. u(i iiKilhem Afd. V. 4. 46 358 58 Orbital niaigiii nol fissured above, a triangular notch below the outer angle. The antennary flagelUim arises in the orbital hiatus. There are three anlero-lateral teeth, the first sub- truncate, the second and tliird acutely pointed. Between the first tooth and the orbital angle there is a spinule. Postero-lateral margins considerably longer than the antero-lateral, straight. Chelipeds very unequal, granulous, granules small, beadlike, and dense on the palms. Pollex of larger hand short, with four principal teeth. The dark color does not quite cover the surface of either thumb. Dimensions. — Ç, length 38 mm., width 57 mm. Koh Chang, 1 fath., coral; I— III; 3 c? 2 ? (1 ? type). In shape resembles A. tomentosiis Dana (pi. XIV, figs. 2a~c, Crust. U. S. Expl. Exped.) which has the carapace without granules and covered with a tomen lu m . Fig. 42. Actiimnus cltangcnsis, Koh Chang, c?, •i^^ mm. wide: a, right cliela ; /). left chela. Actuninus squamosus (de Haan). Cancer (Piluiunus) squamosus de Haan, Fauna Japon., Crust., p. .'in, 18.35. Actumnus squamosus A. Milne Kdwahds, Nouv. Arch. Mus. Hist. Nat., Paris, I, p. :iK(i, pl. XVIH, fig. (i, (ia, (il), Oc, 1800. 20 miles E. S. E. of Koh Samit, 13 14 falb., sandy mud, shells; II. 2; Id". Between Koh Mesan and Cap Liant, 9 fath.; II. 4; 1 c?. Ofi" Koh Sakait, 5—6 fath., sand; II. 23; 1? ovig. Koh Chuen, 30 fath., shell bottom; II; 1 c? 1 ?• Between Koh Rin and Clifi' Rock, (N. of Koh Kram), 15 fath.; III. 2; 1 ?. Koh Kam, 5 fath., gravel; II. 6; 3 0* 3? (1 ovig.) 2 juv. Parapleurophrycoides roseus Nobili. ParapleuropUnjcoides roseus Nobili, Bull. Mus. Hist. Nat., Paris, 1900, No. ,'>, p. 9. About 15 miles W. of Koh Kut, about 30 fath. (s. m.); I. 28; 1 juv., 125 mm. long, 14 mm. wide, front OO mm. This corresponds very well with Nobili's preliminary description. The eyes are of huge size, projecting sideways beyond the orbits. Outer angle of orbit spiniform, as is al.so the lower inner angle; lower margin serrulate. Antenna standing loosely in the orbit, the joint following the basal joint barely reaching the front. Heteropanope sexangula Rathbun. Plate II, fig. 0. Heterqpanope sexangula Ratiirun, Proc. Biol. Soc Washington, XXII, p. IH, 1909. Carapace narrow, hexagonal, little convex, surface tomentose, uneven, a blunt transverse ridge on each frontal lobe, and on each protogastric lobe, and a few irregular nodules on the branchial region. 59 359 Front strongly deflcxed, ils lower edge bearing four small well separated lobes, the inner pair more produced (or lower down), the outer pair distinctly separated from the orbital angles. The upper margin of the orbit has two very small notches; below the outer angle is a very large notch. The short antero-lateral margin is cut into four teeth, first three blunt, fourth largest, acute; first fused witli orbital angle, third minute. Chelipeds and legs tomentose: chelipeds unequal in the ?, stout, 1>;. times as long as carapace. Merus ^^S- ^^ chela otllelcropanope . . , . sexangula, type 9- 7 mm. wide. with a superior, subterminal spine; wrist nodular, with a sharp inner spine; palms granulöse except on the distal portion of the larger one. Legs slender. Length of ovigerous Ç 52 mm., width 7 mm. Gulf of Siam (special locality not given), 1 $. This species in form resembles H. eucratoides Stimpson (Smithson. Misc. Coll., XLIX, 64, pi. VIII, fig. 2, 2a, 1907) which is a much smoother species, the hand being quite smooth. Subfamily Oziinæ. Epixanthus frontalis (Milne Edwards). Epixanihus frontalis Alcock, LXVIl, 185, 1898. Koh Chik, rocky coast; I. 30; 3 (^ 2?. Subfamily Eriphiinæ. Eriphia sebana smithii Mac Leay. Eripbia hcvimana var. Smithii Alcock, LXVII, 21(), 1898. South coast of Koh Chang, sand (shrimp-net); I. 18; 1 ?. Subfamily Trapeziinæ. Trapezia cymodoce (Herbst). Trapezia cymodoce Alcock, L.WII, 219, 1898. Koh Kahdat, coral and coral blocks, 1 falh.; I— II; 1?. Tetralia glaberrima (Herbst). Tetralia (jhihcrrima Alcock, LXVII, 22;!, 1898. Koh Kahdat, coral and coral blocks, 1 fath.; I— II; 7 c? 9 Ç ovig. 2 juv. 4(;' 360 60 Family Potamonidæ. Subfamily Potamoninæ. Potamon (Potamon) brousmichei Ralhbun. Polamon (Potamon) brousmichei Rathbun, Nouv. Arch. Mus. Hist. Nat. (4), VI, 272, lig. 12 in text, pi. X, Hg. 6, 1904. River on Koh Chang; I. 5; 4c? 2Ç 4 juv. Koh Kut, in little mountain river; 1 juv. Bay at Klong Salakpet (River on Koh Chang); III. 14; 1 c?. Klong Salakpet (River on Koh Chang); III. 15; 2 juv. Family Portunidæ. Subfamily Carupinæ. Carupa læviuscula Heller. Carupa laeviuscula Alcock, LXVIII, 20, 1899. Koh Chang, among corals, 1 fath.; Ill; 1 Ç. Subfamily Portuninæ. Scylla serrata (Forskâl). Scylla serrata Alcock, LXVIII, 27, 1899. Coast at Lem Ngob, 6 specimens. "Caught in great numbers in the mangrove. It is eaten by the natives; its flavor I found quite excellent". Portunus sanguinolentus (Linnæus). Nepluniis sanguinolenliis Ai.cock, LXVIII, 32, 1899. At South point of Koh Chang in Sargassum; 1. 8; 2 juv. (1 minule). Koh Kahdal, 1 fath., sandy bottom, sponges, dead corals; I. 11 ; 1 juv. (minute). 18 miles West of Koh Chang, surface; I. 31; 12 juv. (mostly minute). North of Koh Samil, surface; II. 3; 1 juv. (minule). Between Koh Mesan and Koh Chuen, on and under plants, surface; II. 5; 2 juv. North of Koh Chang, under leaves, seaweed, etc.; II. 10; 17 juv. N. side of Koh Chang, under leaves, surface; III. 8; 3 juv. (minute). South of Koh Chang, under floating Sargassum, "rain, not sun"; III. 13; 4 juv. (minute). South of Koh Chang, under floating Sargassum; III. 16; 2 juv. (minute). Portunus pelagicus (Linnæus). Neptuniis pelagicus Alcock, LXVIII, 34, 1899. Coast at Lem Ngob; XII. 30. 99; 3 specimens. Coast at Lem Ngob (seine); XII. 26; 5 (^ 1Ç (all young). Coast at Lem Ngob, 0—1 fath., stones, mud; XII; 61 361 2 c? 2 Ç 5 jiiv. Coasl of Koh Kong; I. 23; 4 Ç juv. Fishing-weir at Koh Kong; I. 21; le?. The shore outside the Mangrove at the Station on Koh Chang; III. 11; 2 juv. Outside mangroves on Koh Chang, very shallow water; III. 18; 1 juv. Portunus (Achelous) gladiator (Fabricius). Neplunus (Amphitrite) gladiator Alcock, LXVIll, 35, 1899 (Not Amphitrite media Stimpson). Between Koh Mesan and Cap Liant, 9 fath. ; II. 4; 2 juv. Koh Kam, 5 fath., gravel; II. 6; 1 c?. Between Koh Rial and Koh Mesan, 3 — 5 fath., sand, algæ; II. 7; 1 juv. Gulf of Rayong, 7 — 10 fath., sand, mud, shells; II. 8; 1 juv. Portunus (Achelous) hastatoides (Fabricius). Neptiinus {Hellenus) hastatoides Alcock, LXVIII, 38, 1899. Singapore, 2—3 fath.; XII. 4; 3 c? 4 ? (1 with Rhizocephalid). Between Koh Kut and Koh Kahdat, 10 fath., shell bottom; I. 10; 2?. S. of Koh Bidang, 9 fath., mud, shells; I. 18; 1 ?. N. of Koh Kong, 8 fath., mud bottom; I. 23; 1 leplunus {HcUeniis) spinipes Alcock, LXVIII, 39, 1899. S. of Koh Kut, 17—20 fath., mud (large seine); I. 28; 2 c? 1?. 10-12 miles west of Koh Chang, 20 fath., mud; I. 29; 5c?. 20 miles south of Koh Samit, 20 fath., mud; I. 31; 2c?. Portunus (Achelous) tenuipes (de Haan). Neplunus (Hellentis) tenuipes Alcock, LXVIII, 42, 1899. 4 miles S. of Koh Sakait, 9 fath , shell bottom; II. 3; 1? ovig. Gulf of Rayong, 7 — 10 fath., sand, mud, shells; II. 8; 1 c?. Koh Kam, 5 fath., gravel; II. 6; 1 c? juv. Between Koh Rial and Koh Mesan, 3 — 5 fath., sand, algæ; II. 7; 1 juv. 6 miles east of Cap Liant, 9 fath., shell bottom; II. 7 ; 2 Ç. Koh Kahdat, 4 — 5 fath., 362 62 sand, stones, coral; II. 15—18; 7 J". Koh Kahdat, 5 — 8 fath., sand, mud; II. 10 and III. 4; 2 juv. Portunus (Achelous) tuberculosus (A. Milne Edwards). Neptiiims (Hcllenns) lubercnlosus Alcock, LXVIII, 42, 1899. Between Koh Kut and Koh Kahdat, 10 fath., shell bottom; I. 10; 1 c?. Between Koh Mesan and Cap Liant, 5 — 8 fath., sand, stones; II. 7; 1 juv. S. of Koh Mak, 5 — 6 fath.; II. 7; 1 juv. Koh Kahdat, 4 — 5 fath., sand, stones, coral; II. 15 18; 1 ?. Koh Kahdat, 5—8 fath., sandy mud; II. 16 and III. 4; 1 c?. Koh Kram, 30 fath.; III. 2 and 21 ; 2 ? (1 ovig.). Portunus (Achelous) brockii (de Man). Nepliinus {Hellenus) brockii Alcock, LXVIII, 43, 1899. Koh Kahdat, 4 5 fath., sand, stones, coral; II. 15 — 18; 1 juv. S. of Koh Mak, 5-6 fath.; II. 17; 2 c?. Sound al Koh Chang, 3—5 fath., soft clay bottom; 1900; 1 c?. Portunus (Achelous) granulatus (Milne Edwards). Neptnniis [Achelous) granulatus Alcock, LXVIII, 4,"), 1899. Koh Kahdat, 4 — 5 fath., sand, stones, coral; II. 15 — 18; 6 c? 2 Ç. Portunus (Lupocycloporus) gracilimanus (Stimpson). Neplunus (Lupocycloporus) whitei Alcock, LXVIII, 44, 1899. Amphilrilc gracilimanus Stimpson, Smithson. Misc. Coll., XLIX, 77, pi. X, fig. 3, 1907 Singapore, 2—3 fath.; XII. 4; 1 c?. Between Koh Kut and Koh Kahdat, 10 falh., shell bottom; I. 10; 1 c? 1 Ç. Between Koh Mesan and Cap Liant, 9 fath.; 11. 4; 3 juv. Koh Kram, 5 fath., gravel; II. 6; 1 juv. Gulf of Rayong, 7 — 10 fath., sand, mud, shells; II. 8; 2 juv. Tung Kaben, 6 fath., sand, mud, phanerogams; II. 22; 2 juv. Koh Chuen, 30 fath., shell bottom; II; 5?. Koh Lan, 30 fath., mud; 1 J" 1 juv. Between Koh Bin and Cliff Rock (N. of Koh Kram), 15 fath.; III. 2; 1?. Portunus (Lupocycloporus) innominatus Rathbun. Neptunus [Lupocycloporus) gracilimanns Alcock (not Stimpson) LXVIII, 45, 1899. Portunus [Lupocycloporus) innominatus Hathbun, Proe. Biol. See. Washington, X.XII, p. 114, 19U9. Koh Kahdat, 8—10 fath., mud; I. 27; 1 ? ovig. 10 miles E. of Koh Mak, 20 fath., large seine; I. 28; 1 c?. Besides the distinguishing characters given by Alcock, the antero-lateral teeth are irregular, the 2nd, 3rd, 4lh and 6lh being smaller than the others. 63 363 Portunus (Xiphonectes) longisp nosus (Dana). Neptuniis (Hellcnus) longispinosus Alcock, LXVIII, 40, 189!). Koh Kahdat, 1 fatli., sandy bolloni, sponges, dead corals; I. 11; le?. S. of Koh Mak, 5—6 fath., II. 7; 2 juv. Koh Kahdal, 4—5 falh., sand, stones, coral; II. 15-18; 25 c? 25? (13 evig.). Subfamily Thalamitinæ. Lissocarcinus boholensis Semper. Lissocarciniis boholensis Semper, in Nauck, Zeits. Wiss. Zool., XXXIV, pp. 00 and 07, 18H0. 15 miles West of Koh Kut, in Salpæ, 1 ? immature. This small specimen is very little broader than long (3'7 mm. long, 38 mm. broad)'. The anterior two-thirds of the carapace approaches a circular form, the postero-lateral margins arc concave, and meet the broad and lightly concave posterior margin (which is half as wide as the carapace) at a blunt obtuse angle. Dorsal surface nearly flat and crossed by fine transverse lines, which are very apparent and fairly continuous on the anterior half but posteriorly become fainter and more broken. Fronto-orbital distance very little less than extreme width. Front strongly projecting and (exclusive of orbital angles) about one-third width of carapace, bilobed, with a distinct median emargination and a short median furrow, each lobe sloping backward and outward and with nearly straight margin. Inner orbital angle subacute. Orbit large, its upper border entire. Eye very large. Antero-Iateral border thin, cut into five (including the orbital) short blunt teeth, scarcely projecting, and indicated more by the furrows between them. Basal joint of antenna narrow, its outer angle produced. The exclusion of the llagellum from the orbit is very slight. Antennules very large, obliquely folded. Chelipeds stout, but little longer than carapace; surface finely roughened. Inner angle of wrist dentiform. Hands full, wider than their superior length, two granular ridges above and one or more obscure ridges on outer surface. Fingers deeply grooved, not gaping, and crossing some distance behind the tips. Legs narrow, first three pairs as long as chelipeds; merus of last pair one and one-half times as long as wide, its posterior border, as well as that of the merus, smooth. Shape of carapace and front something as in L. polybioides Adams & White (c/". Alcock, LXVIII, p. 19, 1899), but anterior and posterior margins wider, orbits much larger, side teeth more as in L. orbicularis Dana (c/'. Alcock, op cit., ]>. 20). Charybdis cruciata (Herbst). Chanjbdis {Goniosoma) crncifera Alcock, LXVIII, 51, 1899. Fishing-weir at Koh Kong; I. 21; 2?. S. of Koh Kut, 17-20 fath., mud (large seine); I. 28; 1 ? 2 juv. Paknam-w^en; II. 11; 1 ?. 18 miles W. of Koh ' Nauck says, on page 67, "langer als breit", but on page CU the dimensions are given as 14 mm. long, 17 broad. Cf. footnote on page 18. 364 • 64 Chang, surface; I. 31 ; 6 juv. S. of Koh Chang, under floating sargassum, "rain, no sun"; HI. 13; 1 juv. 35 miles W. of Koh Chang, 30 fath., day; I. 31; 1 juv. Charybdis lucifera (Fahricius). Plate II, fig. 10. Chttryhtlis (Goniosoma) qnadiimaculala Alcock, LXVllI, 54, 1899. Coast of Leni Ngob, 0 — ^1 fath., stones and mud; XII; 1 Ç. Fishing-weir at Koh Kong; I. 21; 1 cJ* 1? ovig. In one of the colypes before me of Goniosoma quadrimaciilatnm A. Milne Edwards from Batavia {[)]. II, fig. 10) the first antero-lateral tooth is bluntly angled on its outer margin, but this is not the case in the three smaller specimens from the Gulf of Siam. In the two largest individuals examined Ihe orbit is one-third as wide as the front, and in the smallest individual the orbit is somewhat wider. Charybdis annulata (Fabricius). Charybdis (Goniosoma] anniiUita Ai.CdCK, LXVIII, .')4, 1899. Coast of Koh Kam; II, 5; 1 Ç. Charybdis affinis Dana. Philc II, fig. 11. Charfibdis (Goniosoma) affinis Alcock, LX\'III, öl), 1899. Coa.st of Lem Ngob (seine); XII. 26; 1 d". Charybdis anisodon (de Haan). Portiinus anisodon df. Haan, Fauna Japon., Crust., p. 42, 1835. Mouth of the river Paknam-wen, in Chinamen's tow-nets; I 30; 1 Ç. Sound at Koh Chang, 3-5 fath., soft clay bottom; 1900; 2 juv. Charybdis callianassa (Herbst). Charybdis (Goniosoma) callianassa Alcock, LXVIII, 57, 1899. Fishing-weir at Koh Kong; I. 21 ; 1 c?- Oil Koh Kut, 6 falh.; I. 26; 1 ?. Mouth of Paknam-wen (in Chinamen's tow-nets); I. 30; 3c? !?■ Charybdis variegata (Fabricius). Charybdis (Goniosoma) variegata Alcock, LXVIII, 00, 1899. Koh Kam, 5 fath., gravel; II. 6; 1 ? ovig. Koh Kahdat, 4—5 fath., sand, stones, coral; II. 15 18; 1 juv. Charybdis natator (Herbst), Charybdis (Goniosoma) natalor Alcock, LXVIII, (il, 1899. Between Koh Mesan and Cap Liant, 9 fath., II, 4; 1 J* juv. 65 365 Charybdis ornata (A. Milne Edwards). Charybdis {GonioheUenus} ornata Ai.cock, LW'lIl, 04, 189;). Between Koh Kahdat and Koh Kut, 6 falh., sandy clay; I. 9; 2 juv. 20 miles south of Koh Samit, 20 falh., niud; I. 31; le? juv. Koh Kahdat, 5—8 fath., sandy mud; II. 16. and III. 4; 1 c?. Thalamita crenata (Latreille). Thalamita crenata Alcock, LXVIII, 76, 1899. Koh Chang, stony coast at low water; I; 1 ci*. Koh Chang; II. 12; 1 c?. Thalamita prymna (Herbst). Thalamita prymna Aixock, LXVllI, 78, 1899. Singapore, coral reef; XII. 5; 1Ç with Rhizocephalid. Koh Lorn (West of Koh Chang); III. 9; 1?. Thalamita chaptali Audouin. Thalamita chaptali Ai.cock, LXVIII, 80, 1899. Koh Kahdat, 4 — 5 fath., sand, stones, coral; 11.15 — 18; 1 c?, 6 mm. wide, with narrow hands, rather faintly marked, 2' spines (1 acute) on arm; penult segment of abdomen twice as wide as long. 1 Ç ovigerous, 107 mm. wide, with stoutish hands, more strongly marked; 3 acute spines on arm. 1? ovigerous, 222 mm. wide by 161 long, is narrower than typical c/ia/)/a/i or sima, has the side teeth oï chaptali, tlie frontal lobes inclining to sima, the hand stout, with strong markings, only the anterior one of the outer row being obsolete, 3 acute spines on arm. 35 miles West of Koh Chang, 30 fath., clay; I. 31 ; 1 d*, 4 mm. wide. N. of Koh Chang, under leaves, "^ ^^ "^ ^N> seaweed, etc.; II. 10; 1 d' with lateral teeth acute, resembhng ^'S- ^4. Abdomen of those of T. poissonii; chelipeds narrow, hands feebly ridged. j^^^i^ q^^^„„ j Cf. Borradaile, Fauna Maldive Ids., I, pp. 201— 202, 1902, for o 3 mm. wide.' the variations in this species and its allies. Thalamita sima Milne Edwards. Thalamita sima Alcock, LXVIII, 81, 1899. Koh Chuen, 30 fath., shell bottom; I. 2; 2 juv. 15 miles E. of Koh Chuen, 10 fath., shell bottom; II. 2; 1 ?, 1 juv. Between Koh Mesan and Cap Liant, 9 fath.; II. 4; 1 ? with Rhizocephalid. Between Koh Mesan and Koh Chuen, on and under plants, surface; II. 5; 1 juv. Koh Kam, 5 fath., gravel; II. 6; 4 c? 6Ç 17 juv. Between Koh Rial and Koh Mesan, 3 — 5 fath., sand, algæ; II. 7; 2 juv. Between Koh Mesan and Cap Liant, 5—8 fath., sand, stones; II. 7; 2 juv. Koh Kahdat, 4 — 5 fath., sand, stones, coral; II. 15 — 18; 1 juv. Koh Kahdat, 4 — 5 fath., sand, D. K. D. Vidensk. Sclsk. Skr.. 7. K;ckke. n.Tturvidensk. og malhem. Afd. V. 4. 47 366 66 stones, coral; II. 16; 1 juv. Tung Kaben, 6 fath., sand, mud, phanerogams; II. 22; 1? ovig. Koh Chuen, 30 fatli., shell bottom; 11; 1 juv. Koh Chang, 1 fath., coral; I— III; 1 juv. (both 3rd and 4lh side teeth rudimentary). Thalamita imparimanus Alcock. Thalamita imparimanus Alcock, LXVIII, 87, 1899; lUus. Zool. Investigator, Crust., VIII, pi. XLVII, figs. 3, 3 a, 1900. North of Koh Chang, under leaves, seaweed, etc.; II. 10; 1 c?. Differs from the original description in having three spinules present on the outer surface of the wrist; no denticle at base of first side tooth. Between Koh Mesan and Cap Liant, 5 — 8 fath., sand, stones; II. 7; 1 juv., with a strong denticle at base of first side tooth; also spinules on wrist. Subfamily Podophthalmlnæ. Podophthalmus vigil (Fabricius). Podophthalmiis vigil (Fabricius) Miers, Challenger Rept., Zool., XVII, 207, 1886. Sound at Koh Chang, surface; I. 15; 1 ?. (The legs thrown off after it was put in spirit). Fishing-weir at Koh Kong; I. 21; 4 c? 2 Ç. Family Atelecyclidæ. Subfamily Thlinæ. Kraussia nitida Stimpson. Kraussia nitida Rathbun, RuII. Mus. Comp. Zool., XXXIX, 132, plate, fig. 13, 1902; Stimpson, Smithson. Misc. Coll., XLIX, 87, pi. X, fig. 4, 1907. North side of Koh Mesan, 10 — 15 fath., stones, shells; II; 1 juv. Subtribe Dromiacea. Superfaniily Dromiidea. Family Dromiidæ. Dromidia cranioides de Man. Dromidia cranioides Alcock. LXVII, 138, 1899. Between Koh Mesan and Cap Liant, 5—8 fath., sand, stones; II. 7; 1$. Koh Chuen, 30 fath., shell bottom; II; 1 c?, concealed under large sponge. N. of Koh Samit, surface; II. 3; was taken a specimen, one of the later larval stages of a Dromiid, perhaps this species, the last legs strongly resembling those of the adults examined. 67 367 Dromidia unidentata (Rüppell). Dromidia unidentata Alcock, LXVII, 139, 1899. Koh Chuen, 30 falh.; II; 1? with Rhizocephalid attached to, and concealed by, the abdomen. Koh Kram, 30 falh.; III. 2 and 21; 1 d". Koh Kahdal, 5-8 fath., sandy mud; II. 16, III. 4; 1 juv. Cryptodromia canaliculata Stimpson. Cnjplodromia canaliculata Ai.cock, LXVII, 142, 1899; Stimpson, Smithson. Misc. Coll., XLIX, 176, 1907. Between Koh Mesan and Koh Chuen, 30 fath., stones; II. 5; 1 J* juv. A small specimen, only 4-1 mm. long. The nodules of the wrist and hand are very strong; on the wrist are four large, and two or three small nodules; and on the upper surface of the palm five large nodules. Conchoecetes artificiosus (Fabricius). Conchœcetes artificiosus Alcock, LXVIII, 151, 1899. 20 miles E. S. E. of Koh Samit, 13—14 lath., sandy mud, shells; II. 2; Id" 1 ?• Koh Chuen, 30 fath., shell bottom; II; 1 c?- The J' from Koh Chuen is half grown and seems intermediate between C. andamanicus Alcock (op. cit., p. 152) and typical arli/iciosus; the front is cut into two triangular teeth, with the inferior denticle slightly visible in dorsal view; there is a rudimentary tooth on the upper border of the orbit; no traces of lateral teeth, the sides being arcuate; subhepatic region not bounded by distinct rows of tubercles or granules. 47* EXPLANATION OF PLATES. Plate I. Fig. 1. Leucosides uraiiia, Koh Kahdat, c?i 24'9 mm. wide. — 2. Pseudophilijra tridentata, between Koli Mesan and Koh Chuen, d, 6'9 mm. wide. — 3. Piliimnus dorsipes, Koli Kram, Q juv., 10'4 mm. wide, dorsal view. Same specimen as fig. 9. — 4. lialimcde ochlodes, Koh Kahdat, immature Ç, 17'5mm. wide. — 5. Cri/ptopodia Iwinmana, between Koli Mesan and Koh Chuen, 9, 261 mm. wide. — 6. Tijphlocarcinus niidus, between Koh Kahdat and Koli Kut, d, 6'2 mm. wide. — 7. Parlhenope {Pseudolambrus) harpax, Koh Chuen, 9i 27-7 mm. wide. — 8. Pilumnus boiradailei, type d, 10 mm. wide. — 9. — dorsipes, ventral view. Same specimen as fig. 3. — 10. Chasmocarcinops gelasimoides, d, in Amussium pleuronectes. 'U. — 11. Arcania siamensis, type 9i 24-5 mm. wide. — 12. Per.tephona elegans, Koh Chang, c?, 94 mm. wide. — 13. Pseudophilijra melita, between Koli Riat and Koh Mesan, 9, 113 mm. wide. — 14. Leucosides longifrons pulcherrima, Koh Kahdat, cJ, 18 mm. wide. — 15. Pilumnus cærulescens, Koh Kahdat, c?, 10'4 mm. wide. — 16. Leucosides haswelli, Koh Chuen, c?, 17-2 mm. wide. — 17. Ebalia woodmasoni, Koh Kahdat, Ç, 6'7 mm. wide. — 18. Mortensenella forceps, Koli Cliang, c?, 68 mm. wide. — 19. Halimede thurstoni, Koh Kam, 9, 20-8 mm. wide. Plate II. Fig. 1. Thaumastoplax orientalis, type c?, 126 mm. wide. — 2. Scalopidia spinosipes, Koh Samit, d, 19Ô mm. wide. — 3. Macrophthalmus convexus, Koh Chang, o". 19 5 mm. wide. — 4. Merionia lanka, between Koh Mesan and Cap Liant, 9, 5-3 mm. wide. — 5. Megœsthesius sagedœ, type cj, 2-7 mm. wide. — 6. Heleropanope scxangula, type 9, 7 mm. wide. — 7. Halimede thurstoni, Koh Kam, juv., 6*8 mm. wide. — 8. Pinnotheres cardii, between Koh Chuen and Koh Chang, 9, 5-8 mm. wide. — 9. — parvulus, Lem Ngob, 9, 85 mm. wide. — 10. Charybdis lucifera (Fabricius). Cotype of Goniosoma quadrimaculatum A.Milne Edwards, c?, 5cSl mm. wide. — 11. Charybdis af/inis, Lem Ngob, d- 43-6 mm. wide. — 12. Chasmocarcinops gelasimoides, Koh Chang, cf, 13'1 mm. wide. — 13. Xenophthalmus obscurus, Koh Kut, d, 9-1 ram. wide. — 14. Asthenognathus hexagonum, type 9, 7-8 mm. wide. — 15. Cycloxantlwps lineatus, north of Koh Chuen, d, 7 2 mm. wide. — 16. Typhlocarcinops canaliculata, type d, 36 mm. wide. — 17. Philyra olivacca, type d, 78 mm. wide. — 18. Carpilodcs lophopus, between Koh Mesan and Koh Chuen, 9. 105 mm. wide. Dan. Exp. to Stam. Zool. Res. (M. J. Rathhun). K. D. Vidensk. Selsk. Skr.. 7 R., n.-m. Afd. V, i. Tab. 1. Pacht & Crone phototyp. Dan. Exp. (o Siam. Zool. Res. (M. J. Rathhun). K. D. Vidensk. Selsk. Skr.. 7 R., n.-m. Afd. V, i. Tab. 11. Pacht & Crone phototyp. Mémoires de l'Acadéniie Royale des Sciences et des Lettres de Danemark, Copenhague, 7™« série. Section des Sciences, t. V, n" ! rechp:rches SUR.QUKl.QUES GENERAI. ISATIONS DUNE IDENTITÉ INTÉGRALE D'ABEL PAK NIELS NIELSEN D. Kgl. Danske Vidensk. Selsk. Skrifter, 7. Række, naturvidensk. og mathem. Afd. V. 1 ■-CJtxS«:»-« KØBENHAVN HOVEDKUMMISSIONÆR: ANDR. FRED, HØST & SØN. KGL HOF-BOGHANUEL BIANCO LUNOS BOGTRYKKERI 1907 Pris: 1 Kr. 20 0. Det Kgl. Danske Videnskabernes Selskabs Skrifter, 6te Række. Naturvidenskabelig og matliematisk Afdeling. Kr. Øre I, med 42 Tavler, 1880—85 29. 50. 1. Prjt», K. undersøgelser over Lysets Brydning i Dampe og tilsvarende Vædsker. 1880 65. 2. Boas, J. E. V. Studier over Decapodernes Slægtskabsforhold. Med 7 Tavler. Résumé en français. 1 880 8. 50. 3. Steeiistrup, Jap. Scpiadarium og Idiosepius, to nye Slægter af Scpiernes Familie. Med Bemærliningcr om to beslægtede Former Sepioloidea DOrb. og Spirula Lmk. Med I Tavle. Resumé en français. 1881 I. 35. 4. Colding, A. Nogle Undersøgelser over Stormen over Nord- og Mellem-Europa af 12'''— 14'''= Novb. 1872 og over den dermed fremkaldte Vandflod i Østersøen. Med 23 Planer «g Kort. Resumé en français. 18S1 10. » 5. Boas, J. Ë. T. Onî en fossil Zebra-Form fra Brasiliens Campos. Med et Tillæg om to Arter af Slægten Ilippidion. Med 2 Tavler. 1881 2. . 6. Steeii. A. Integration af en lineær Dilfcrentialligning af anden Orden. 1882 50. 7. Krabbe, B. Nye Bidrag til Kundskab om Fuglenes Bændelorme. Med 2 Tavler. 1882 1. 35. 8. Baiinover, A. Den menneskelige Hjerneskals Bygning ved Anencephalia og Misdannelsens Forhold til Hjerneskallens Primordialbrusk. Med 2 Tavler. Extrait et explltatioii des planches en français. 1882 1. 60. 9. Den menneskelige Hjerneskals Bygning ved Cyclophi og Misdannelsens Forhold til Hjerneskallens Primordialbrusk. Med 3 Tavler. Extrait et explic. des planches en français. 1884 4. 35. 10. Den menneskelige Hjerneskals Bygning ved Synotia og Misdannelsens Forhold til Hjerneskallens Pri- mordialbrusk. Med 1 Tavle. Extrait et explic. des planches en français. 1884 I. 30. 11. Lehmann, X. Forsog paa en Forklaring af Synsvinklens Indflydelse paa Opfattelsen af Lys og F'arve ved direkte Syn. Med 1 Tavle. Resumé en français 1885 1. 85. II, med 20 Tavler, 1881—86 20. •■ 1. Warming, Eug. F'amilien Podostemaceae. 1*'" Afhandling. Med 6 Tavler. Résumé et explic. des planches en français. 1881 3. 15. 2. Lorenz, L. Om Metallernes Ledningsevne for Varme og Elektricitet. 1881 1. 30. 3. Wanning, Eug. Familien Podostemaceae. 2''^" Afhandling. Med 9 Tavler. Resume et explic. des planches en français. 1882 5. 30. 4. Christensen, Odin. bidrag til Kundskab om Manganets lller 1883 I. 10. 5. Lorenz, L. F'arvespredningens Theori. 1883 60 6. Gram, J. P. Undersogelser ang. Mængden af Primtal under en given G-'ænse. Résumé en français. 1884 4. » 7. Lorenz, L. Bestemmelse af Kviksølvsøjlers elektriske Ledningsmodstande i absolut elektromagnetisk Maal. 1885 .' - 80. 8. Trausledt, M. P. A. Spolia Atlantica. Bidrag til Kundskab om Salperne. Med 2 Tavler. Explic. des planches en français. 1885 3. " 9. Bohr, Chr. Om Iltens Afvigelser fra den Boyle-Mariotteske Lov ved lave Tryk. Med 1 Tavle. 1885 ... I. « 10. Undersøgelser over den af Blodfarvestolfet optagne Iltmængde udførte ved Hjælp af et nyt Absorplio- meter. Med 2 Tavler. 1886 1. 70. 11. Thiele, T. N. Um Definitionerne for Tallet, Talarterne og de tallignende Bestemmelser. 1886 2. » III, med 6 Tavler, 1885—86 16. • 1. Zeuthen, B. G. Keglesnitslæren i Oldtiden. 1885 10. • 2. Le?lnsen, G. Kl. R. Spolia Atlantica. Om nogle pelagiske Aniiulatu. Med 1 Tavle. 1885 1. 10. 3. Rung, G. Selvregistrerende meteorologiske Instrumenter. Med 1 Tavle. 1885 1. 10. 4. Meinert, Fr. De encéphale Myggelarver. Med 4 dobb Tavler. Résumé et explic. des planches en français. 1886 6. 75. iv, med 25 Tavler. 1886-88 21. 50. 1. Boas, J. E. V. Spolia Atlantica. Bidrag til Pteropodernes Morfologi og Systematik samt lil Kundskaben om deres geografiske Udbredelse. Med 8 Tavler. Resumé en français. 1886 10. 50. 2. Lehmann, A. Om Anvendelsen af Middelgradationernes Metode paa Lyssansen. Med 1 Tavle. 1886 . . 1. 50. 3. Hannover, A. Primordialbrusken og dens Forbening i Truncus og Extremiteter lios Mennesket for Fød- selen. Extrait en français. 1887 1. 60. 4. Lùtken, Chr. Tillæg til «Bidrag til Kundskab om Arterne af Slægten Cyainus Latr. eller Hvallusene-. Med 1 Tavle. Résumé en français. 1887 60. 5. Fortsatte Bidrag til Kundskab om de arktiske Dybhavs-Tudsefiske, særligt Slægten Himantolophus. Med 1 Tavle. Resumé en français 1887 75. 6. Kritiske Studier over nogle Tandhvaler af Slægterne Tursiops, Orca og Lagenorhynclms. Med 2 Tavler. Resumé en français 1887 4. 75. 7. Koefoed, E. Studier i Platosoforbindelser. 1888 I. 30. 8. Warming, Eug. Familien PodostemVeae. 3*'«^ Afhandling. Med 12 Tavler. Résumé et explic. des planches en français. 1888 6. 45. V, med 11 Tavler og 1 Kort. 1889—91 15 50. 1. Lutken, Chr. Spolia Atlantica. Bidrag til Kundskab om de tre pelagiske Tandhval-Slægter Steno, Del- phinus og Prodelphinus. Med I Tavle og I Kort. Résumé en français. 1889 2. 75. 2. Valentiner, H. De endelige Transformations-Gruppers Theori. Résumé en français. 1889 5. 50. 3. Hansen, H. J. Cirolanidæ et familiæ nonnullæ propinguæ Musci Hauniensis. Et Bidrag til Kundskaben om nogle Familier af isopode Krebsdyr Med 10 Kobbertavier. Résumé en français. 1890 9. 50. 4. Lorenz, L. Analytiske Undersøgelser over Primtalmængderne. 1891 » 75. ( Foi-taættes paa Umslagets S, 3.) (Forts, fra Omtilagetg S. 2.) Kr. Øre VI, med 4 Tavler. 1890—92 13. 75. 1. Lorenz, L LysbevægeUen i og uden for en af plane Lysbølger belyst Kugle. 1890 2. • 2. S»reiiseii, Wllllaiii. Om Furbeniiiger I Svemmeblæren, Pleura og Aortas Væg og Sammensmeltningen deraf med Hvirvelsøjlen særlig hos Siluroiderne, samt de saakaldte Weberske Knoglers Morfologi. Med 3 Tavler. Resumé en français. 1890 : 3. 80. 3. Wanning, Bug. Lagoa Santa. Et Bidrag til den biologiske Plantegeografi. Med en Fortegnelse over Lagoa Santas Hvirveldyr. Med 43 Illustrationer i Texten og 1 Tavle. Résumé en français. 1892 10. 85. VIX, med 4 Tavler. 1890-94 13. 75. 1. Gram, J. P. Studier uver nogle numeriske Funktioner. Résumé en français. IX9U 1. 10. 2. Prjti, k. Methoder til korte Tiders, særlig Rotationstiders, Udmaaliiig. En experimental Undersøgelse. Med 16 Figurer i Texten. 1890 1. 50. 3. Petersen, Emil. Om nogle Grnndstoll'ers ätiotrope Tilstandsformer. 1891 I. 60. 4. Warming, Eng. Familien Podosteraaceae. 4''« .■Vlhandling. Med c. 18.i mest af Forfatteren tegnede Figurer i 34 Grupper. Résumé et explication des ligures en français. 1891 1. 50. 5. Christensen, Odin T. Khodanchromammoniakforbiiidelser. (Bidrag til Chromammoniakrorbindelsernes Kenii. III.) 1891 ■ 1. 25. 6. Lutken, Chr. Spolia Atlantica. Scopelini Musei Zoologie! Universitatis Hauniensis. Bidrag til Kundskab om det aabne Havs Laxesild eller Scopeliner. Med 3 TÏvIer. Résumé en français. 1892 3. 50. 7. Petersen, Emil. Om den elektrolytiske Dissociationsvarme af nogle Syrer. 1892 1. 25. 8. Pelersen, O.G. Bidrag til Scitamineernes Anatomi. Résumé en français. 1893 .... 2. 75. 9. Lülken, Chr. Andet Tillæg til »Bidrag til Kundskab om Arterne af Slægten Cyamus Latr. eller Hval- lusene». Med 1 Tavle. Resumé en français. 1893 85. 10. Petersen, Emil. Reaktionshastigheden ved Methylætherdannelsen. 1894 1. 50. VIII, med 3 Tavler. 189.5-98 12. 25. 1. Meinert, F. Sideorganerne hos Scarabæ- Larverne. Les organes latéraux des larves des Scarabés Med 3 Tavler. Resumé et explication des planches en français. 1895 3. 30. 2. Petersen, Emil. Damptryksformindskelsen af Methylalkohol. 1896 1. . 3. Bnchvaldl, F. En mathematisk Undersøgelse af, hvorvidt Vædsker og deres Dampe kunne have en fælles Tilstandsligning, baseret paa en kortfattet Fremstilling af Varmetheoriens Hovedsætninger. Resumé en français. 1896 2. 25. 4. Warming, Eug. Halofyt-Studier. 1897 3. . 5. Johannsen, W. Studier over Planlernes periodiske Llvsyttringer. 1. um antagonistiske Virksomheder i Stofskiftet, særlig under Modning og Hvile. 1897 3. 75. 6. Melsen, N. Undersøgelser over reciproke Potenssummer og deres Anvendelse paa Rækker og Integraler. 1898. 1. 60. IX, med 17 Tavler. 1898-1901 17. • 1. Steenstrup, Japetus, og Luiken, Chr. Spolia Atlantica. Bidrag til Kundskab om Klump- eller Maaneflskene (Molidæ). Med 4 Tavler og en Del Xylografier og Fotogravurer. 1898 4. 75. 2. Warming, Eug. Familien Podostemaceae. .5'« Afhandling. Med 42 Figurgrupper. Résumé en français. 1899 1. 60. 3. Meyer, Kirstine. Om overensstemmende Tilstande hos Stofferne. En med Videnskabernes Selskabs Guld- medaille belønnet Prisalhandling. Med en Tavle. 1899 2. 60. 4. Jorgensen, S. M. Om Zeise's Platosemiæthylen- og Cossa's Platosemiamminsalte. Med I Tavle. 1900 . . -75. 5. Christensen, A. Om Overbromider af Chinaalkaloider. 1900 1. 6. Steenstrup, Japetus. Heteroteuthis Gray, med Bemærkninger om Rossia-Sepiola Familien i Almindelighed. Med en Tavle. 1900 90. 7. Gram, Bille. Om Proteinkornene hos olieglvende Frø. Med 4 Tavler. Résumé en français. 1901 ... 2. 50. 8. Meinert, Fr. Vandkalvelarverne (Larvæ Dytiscidarum). Med 6 Tavler. Résumé en français. 1901 . . 5. 35. X, med 4 Tavler 1899—190:' 10. 50. 1. Juel, C. Indledning i Læren om de grafiske Kurver. Résumé en français. 1899 2. 80. 2. Blllmann. Eluar. Bidrag til de organiske Kvægsølvforbindelsers Kemi. 1901 1. 80. 3. Samsee Lund og Rostrup, E. Marktidselen (Cirsium aroensej. En Monografi. Med 4 T-avler. Résumé en français, luoi 6 4. Christensen, A. um Bromderivater af Chlnaalkaloiderne og om de gennem disse dannede brintfattigere For- bindelser. 1902 1. 40. XI, med 10 Tavler og 1 Kort. 1901-03 15. 05. 1. Warming, Eug. Familien Podostemaceæ. (j'e Afhandling. Med 47 Figurgrupper. Resumé en français. 1901. 2. là. 2. Ravn, J. P. J. Molluskerne i Danmarks Kridtaflejringer. 1. Lamellibranchiater. Med 1 Kort og 4 Tavler. 1902. 4. ■ 3. Winther, Chr. Rotationsdispersionen hos de spontant aktive Stolfer. 1902 2. ■ 4. Ravn, J. P. J. Molluskeriie i Danmarks Kridtaflejringer. II. Scaphopoder, Gastropoder og Cephalopoder. Med 5 Tavler. 1902 .' 3. 40. 5. Winther, Chr. Polarimetriske Undersøgelser II: Rotationsdispersionen i Opløsninger 1. 60. 6. Ravn, J. P. J, Molluskerne i Danmarks Kridtaflejringer. 111. Stratigraûskc Undersøgelser. Med I Tavle. Resumé en français. 1903 .' 3. 85. XII, med 3 Tavler og 1 Kort. 1902-04 10. 50. 1. Forch, Carl, Knudsen, Martin, und Sarensen, S. P. L. Berichte über die Konstantenbestimmungen zur Auf steiluug der hydrographischen Tabellen. Gesammelt von Martin Knudsen. 1902 4. 75. 2. Bergh, R. Gasteropoda opisthobranchiata. With three plates and a map. (The Danish expedition to Slam I89U - 1900, I.) 1902 3. 45. 3. Petersen, C. G. Joh., Jensen, Seren, Johansen, A. C, og Levinsen, J. Chr. L. De danske Farvandes Plankton i Aarenc 1898—1901. 1903 3. 25. . 4. Christensen, A. Om Chinaalkaloidernes Dibromadditionsprodukter og om Forbindelser af Alkaloiderne« Chlorhydrater med højere Metalchlorider. 1904 1. 35. Mathematiske og astronomiske Skrifter udgivne af Det Kgl. Danske Videnskabernes Selskab (udenfor Skrifternes 6. Række, so Omslagels S. 2 — 3) : Kr. Øre Hansen, P. C. V. En Sætning om den Eulerske Faktor svarende til Dillerentialligningen M + N ^^ = 0. 73. ■ G5. üansleen, C. Den magnetiske Inclinalions Forandring i den nordlige tempcrerle Zone 1, med et Kort. .Oâ. 2. » II. 57 ■ 1- 15- HerlzspruDg, 8. Reduktion af Maskelynes Iagttagelser af smaa Stjerner. 65 1. 15. Ilamus, C. Undersøgelse af Resten i Lagranges Række, samt: Om en Egenskab ved de lineære Dltt'erentlal- Ligninger med 2 Variable. 42 " *>5. Om nogle Curvers Rectification ved elliptiske Functioner. 45 » 50. Om Ellipsoiders Tiltrækning og om de ellipsoidiske LigevægtsOgurer af flydende Masser. 45 I. 65. Schjellerup, B. C. K. C. Tycho Brahes Original-Observationer benyttede til Hanebestemmelse af Cometen 1580. 54. 1. ■ Steen, X. Hovedsætninger om de overelliptiske Funktioner og; Om dobbelte bestemte Integraler. 49 »65. Om Integrationen at Differentialligninger. Résumé en français. (iS • 35. Om Ændringen af Integraler af irrationale Differentialer. 69 ■ 40. Læren om homogene tunge Vædskers Tryk paa plane Arealer, m. 1 Tavle. Resumé en français. 72 . » 75. Om Muligheden af et Par lineære Differentialligningers Integration ved endelige explicite Funktioner. 75. » 75. Thiele, T. Bi. Om Anvendelse af mindste Kvadraters Methode i nogle Tilfælde, hvor en Komplikation af visse Slags uensartede tilfældige Fejlkilder giver Fejlene en «systematisk» Karakter. 80 ■ 85. leutheu, H. 0. Almindelige Egenskaber ved Systemer af plane Kurver, m. 5 Tavler. Résumé en français. 73 . 3. 60. d'Arrest, H. L. Siderum nebulosorum observatlones Havnienses. 67 12. ■• Hansen & Olufsen. Tables du soleil. 53 4. • Supplément aux tables du soleil. 57 " 35. Jùrgensen, Chr, Sur le mouvement du pendule. 53 • 65. SclOellerup, H. C, F. C. Stjernefortegnelse, indeholdende 10,000 Positioner og teleskopiske Fi.vsljeiner imellem — 15 og + 15 (Jraders Deklination. Med 1 Tavle. Hi 7. • TEKNISK HTH Mémoires de TAcademie Royale des Sciences et des Lettres de Danemark, Copenhague, 7™— KØBENHAVN HOVEDKOMMISSIGNÆR: ANDR. FRED. HØST & SØN, KGL. HOF-BOGHANDKL BIANCO LUNDS BOGTRYKKERI 1909 Pris: 8 Kr. 60 Øre. Det Kgl. Dauske Videnskabernes Selskabs Skrifter, 6te Raekke. Natnryidenskabelig og mathematisk Afdeling. '=''=' <^ Kr. Øre I, med 42 Tavler, 1880—85 29. 50. 1. Prjiz, K. Undersøgelser over Lysets Brydning i Dampe og tilsvarende Vædsker. 1880 65. 2. Boas, J. E. V. Studier over Decapodernes Slægtsltabsforhold. Med 7 Tavler. Résumé en français. ISSO 8. 50. 3. Steenstrup, Jap. Sepiadarium og Idiosepius, to nye Slægter af Hepiernes Familie. Med Uemærkninger om to beslægtede Former Sepioloidea D'Orb. og Spirula Lmk. Med 1 Tavle. Késumé en français. 1881 1. 35. 4. Colding, A. Nogle Undersøgelser over Stormen over Nord- og Mellem-lîuropa af 12"; — U^« Novb. 1872 og over den derved fremkaldte Vandflod i Østersøen. Med 23 Planer og Kort. Résumé en français. ISSl 10. » 5. Boas, J. E. V. Om en fossil Zebra-Form fra Brasiliens Campos. Med et Tillæg om to Arter af Slægten Hippidion. Med 2 Tavler. 1881 2. • 6. Steen, A. Integration af en lineær Difl'erentialligiiing af anden Orden. 1882 50. 7. Krabbe, H. Nye Bidrag til Kundskab om Fuglenes Bændelorme. Med 2 Tavler. 1882 1. 35. 8. BannoTer, A. Den menneskelige Hjerneskals Bygning ved Anencephalia og Misdannelsens Forhold til Hjerneskallens Priniordialbrusk. Med 2 Tavler. Extrait et explication des planches en français. 1882 1. 60. 9. Den menneskelige Hjerneskals Bygning ved Cyclopia og Misdannelsens Forhold til Hjerneskallens Priniordialbrusk. Med 3 Tavler. Extrait et explic. des planches en français. 1884 4. 35. 10. Den menneskelige Hjerneskals Bygning ved Synotia og Misdannelsens Forhold til Hjerneskallens Pri- mordialbrusk. Med 1 Tavle. E.xtrait et explic. des planches en français 1884 1. 30. lt. Lehmann, A. Forsøg paa en Forklaring af Synsvinklens Indflydelse paa Opfattelsen af Lys og Farve ved direkte Syn. Med 1 Tavle. Résumé en français 1885 t. 85. II, med 20 Tavler, 1881-86 20. » t. Warming, Eug, Familien Podostemaceae. l^'^ Afhandling. Med 6 Tavler. Résumé et explic. des planches en français. 1881 3. 15. 2. Loreni, L. Om Metallernes Ledningsevne for Varme og Elektricitet. 1881 1. 30. 3. Warming, Eng. Familien Podostemaceae. 2''<^'' Afhandling. Med 9 Tavlerf Résumé et explic. des planches en français. 1882 5. 30. 4. Christensen, Odin. Bidrag til Kundskab om Manganels Ilter. 1883 1. 10. 5. Lorenz, L. Farvespredningens Theori. 1883 ■ 60. 6. Crani, J. P. Undersøgelser ang. Mængden af Primtal under en given Grænse. Résumé en français. 1884 4. » 7. Lorenz, L. Bestemmelse af Kviksølvsøjlers elektriske Ledningsmodstande i absolut elektromagnetisk ■ Maal. 1885 80. 8. Traustedt, M. P. A. Spolia Atlantica. Bidrag til Kundskab om Salperne. Med 2 Tavler. Explic. des planches en français. 1885 3. « 9. Bohr, Chr, Om Iltens Afvigelser fra den Boyle-Mariotteske Lov ved lave Tryk. Med 1 Tavle. 1885 ... 1. • 10. Undersøgelser over den af Blodfarvestollet optagne Iltmængde udførte ved Hjælp af et nyt Absorptio- meter. Med 2 Tavler. 1886 1. 70. ti. Thiele, T. N. Om Definitionerne for Tallet, Talarterne og de tallignende Bestemmelser. 1886 2. > III, med 6 Tavler, 1885—86 16. ■ 1. Zeuthen, B. G. Keglesnitslæren i Oldtiden. 1885 ■ 10. • 2. Levinsen, C. M. R. Spolia Atlantica. Om nogle pelagiske Annulatu. Med I Tavle. 1885 1. 10. 3. Bung, C. Selvregistrerende meteorologiske Instrumenter Med 1 Tavle. 1885 1. 10. 4. Meinert, Fr. De encéphale Myggelarver. Med 4 dobb. Tavler. Résumé et explic. des planches en français. 1886 6- 75. iv, med 25 Tavler. 1886-88 21. 50. 1. Boas, J.E. y. Spolia Atlantica. Bidrag til Pteropodernes Morfologi og Systematik samt til Kundskaben om deres geografiske Udbredelse. Med 8 Tavler. Résumé en français. 1886 10. 50. 2. Lehmann, A. Om Anvendelsen af Middelgradatiunernes Metode paa Lyssansen. Med 1 Tavle. 1886. ... 1. 50. 3. Hannover, A. Primordialbrusken og dens Forbening i Truncus og Extremiteter hos Mennesket før Fød- selen. Extrait en français. 1887 1. 60. 4. Lutken, Chr. Tillæg til «Bidrag til Kundskab om Arterne af Slægten Cjjamus Latr. eller Hvallusene.. Med 1 Tavle. Résumé en français. 1887 » 60. 5. Fortsatte Bidrag til Kundskab om de arktiske Dybhavs-Tudsefiske, særligt Slægten Himantolophus. Med 1 Tavle. Resumé en français. 1887 75. 6. Kritiske Studier over nogle Tandhvaler af Slægterne Tursiops, Urea og Luiienorhynchus. Med 2 Tavler. Resumé en francais 1887 A. 75. 7. Koefoed, E. Studier i Platosoforbindelser. 1888 1- 30. 8. Warming, Eug. Familien Podostemaceae. S«"'«* Afhandling. Med 12 Tavler. Résumé et explic. des planches en français. 1888 6- -iS. V, med 11 Tavler og 1 Kort. 1889—91 15. 50. 1. Lutken, Chr. Spolia Atlantica. Bidrag til Kundskab om de tue pelagiske Tandhval-Slægter Steno, Del- plUnus og Prodelphiiiiis. Med 1 Tavle og 1 Kort. Resumé en français. 1889 2. 75. 2. Valentiner, H. De endelige Transformations-lirnppers Theori. Résumé en français. 1889 5. 50. 3. Hansen, H. J. Cirolanidæ et familiæ nonnullæ propinquæ Musei Hauniensis. Et Bidrag til Kundskaben om nogle Familier af isopode Krebsdyr. Med 10 Kobbertavler. Késumé en français. 1890 9. 50. 4. Lorenz, L. Analytiske Undersøgelser over Primtalmængderne. 1891 • 75. (Fortsættes paa Oinolagets S. 3.) (Forts, fra Omslagots S. Z.) „_ Kjt. Øre VI, med 4 Tavler. 1890—92 13. 75. 1. Loreni, L. Lysbevægelsen i og uden for en af plane Lysbalger belyst Kugle. 1890 '. . . . 2. • i. Serensen, William. Um Forbeninger i Svømmeblæren, Pleura og Aortas Væg og Sammensmeltningen deraf med Hvirvelsøjlen særlig hos Silurolderne, saml de saakaldte Weberske Knoglers Morfologi. Med 3 Tavler. Resumé en français. tS90 3. gø. 3. Wanning, Eug. Lagoa Santa. Kt Bidrag til den biologiske Plantegeografi. Med en Fortegnelse over Lagoa Santas Hvirveldyr. Med i3 Illustrationer i Texten og 1 Tavle. Resumé en français. 1892 10. 85. VII, med 4 Tavler. 1890-94 13. 75. 1. Gram, J. P. Studier over nogle numeriske Funktioner. Uésumc en français. 1890' 1. 10. 2. Prytz, K. Mellioder til korte Tiders, særlig Rotationstiders, Udmaaling. En experimental Undersøgelse. Med 16 Figurer i Texten. 1890 1. 50. 3. Petersen, Emil. Om nogle GrundstoH'eu ätiotrope Tilstandsformer. 1891 . . .' 1. 60. 4. Wanning, Eng. Familien Podostemaccae. 4''« Afhandling. Med c. 185 mest af Forfatteren tegnede Figurer i 34 Grupper. Resumé et explication des figures ei) français. 1891 (. 50. 5. Chrlsleusen, Odin T. Ithodanchromammoniakforbindelser. (Bidrag til Chromammoniakforbindelsernes Kemi. III.) isni 1. 25. 6. Lutken, Chr. Spolia Atlantica. Scopelini Musei Zoologici Universitatis Hauniensis. Bidrag til Kundskab om del aabne Havs Laxesild eller Seopeliiier. Med 3 Tavler. Résumé en français. 1892 3. 60. 7. Petersen, Emil. Om den eleklrolytiske Dissociationsvarme af nogle Syrer. 1892 1. 25. 8. Petersen, O.G. Bidrag til Scitamineernes Anatomi. Resumé en français. 1893 2. 75. 9. Lutken, Chr. Andet Tillæg til "Bidrag til Kundskab om Arterne af Slægten Gyamtts Latr. eller Hval- lusene». Med 1 Tavle. Résumé en français 1893 ' 85. 10. Petersen, Emil. Reaktionshastigheden ved Methylætherdannelsen. 1894 1. 5Q. VIII, med 3 Tavler. 189.J— 98 12. 25. 1. Meinert, F. Sideorganerne hos Scarabæ- Larverne. Les organes latéraux des larves des Scarabés. Med 3 Tavler. Résumé et explication des planches en français. 1895 3. 30. 2. Petersen, Emil. Damplryksforniindskelsen af Methylalkohol. 1896 I. • 3. ÜHchwaldt, V. En niathematisk undersøgelse af, hvorvidt Vædsker og deres Dampe kunne have en fælles Tilstandsligning, baseret paa en kortfattet Fremstilling af Varraetheoriens Hovedsætninger. Resumé en Irancais. 1896 2. 25. 4. Warming, Eug. Halofyt-Studier. 1897 3. . 5. Johannsen, W. Studier over Planternes periodiske Livsyttringer. I. Om antagonistiske Virksomheder i Stofskiftet, særlig under Modning og Hvile. 1 897 3. 75. 6. Nielsen, N. Undersøgelser over reciproke Polenssummer og deres Anvendelse paa Rækker og Integraler. 1898. 1 60. IX, med 17 Tavler. 1898-1901 17. • 1. Steenstrup, Japetus, og Luiken, Chr. Spolia Atlantica. Bidrag til Kundskab om Klump- eller Maanellskene (Molitlæ). Med 4 Tavler og en Del Xylografier og Fotogravurer. 1898 4. 75. 2. Warming, Eug. Familien Podostemaceae. ö'^ Afhandling. Med 42 Figurgrupper. Resumé en français. 1899 I. 60. 3. Meyer, Kirstine. Om overensstemmende Tilstande hos Stollerne. En med Videnskabernes Selskabs Guld- medaille belønnet Prisafhandling. Med en Tavle. 1899 ." 2. 60. 4. Jergensen, S. M. Om Zeise's Plalosemiætliylen- og Gossa's Plalosemiamminsalte. Med 1 Tavle. 1900 . . «75. 5. Christensen, A. Om Overbromider af Chiiiaalkaloider. 1900 I. • 6. Steenstrup, Japetus. Heteroteuthis Oray, med Bemærkninger om Rossia-Sepiola-Famllien i Almindelighed. Med en Tavle. 1900 . 90. 7. Gram, Bille. Om Proleinkornene hos diegivende Frø. Med 4 Tavler. Résumé en français. 1901 .... 2. 50. 8. Meinert, Fr. Vandkalvelarvernc (Larvæ Dytiscidarum). Med 6 Tavler. Résumé en français. 1901 . . 5. 35. X, med 4 Tavler. 1899—1902 10. 50. 1. Juel, C. Indledning i Læren om de grafiske Kurver. Résumé en français. 1899 2. 80. 2. Blilmann, Einar. Bidrag til de organiske Kvægsølvforbindelsers Kemi. 1901 I. 80. 3. Samsee Lund og Rostrup, E. Marklidselen (Cirsium aroense). En Monografi. Med 4 Tavler. Résumé en français. 1901 6. • 4. Christensen, .4. Om Bromderivater^af Chinaalkaloiderue og om de gennem disse dannede brintfattigere For- bindelser. 1902 I. 40. XI, med 10 Tavler og 1 Kort. 1901-03 »5. 05. 1. Warming, Eng. Familien Podostemaceæ. 6'« Afhandling. Med 47 Figurgrupper. Resumé en français. 1901. 2. 15. 2. Ravn, J. P. J. Molluskernc i Danmarks Kridtaflejringer. 1. Lamellibranchiater. Med 1 Kort og 4 Tavler. 1902. 4. • 3. Winther, Chr. ISotationsdispersionen hos de spontant aktive Stolfer. 1902 2. • 4. Ravn, J.P.J. Molluskenie i Danmarks Kridtallcjringer. II. Scaphopoder, Gastropoder og Gephalopoder. Med .0 Tavler. 1902 3. 40. 5. Winther, Chr, Polarimetriske Uiidersiigelser 11 : Rotalionsdispersionen i Opløsninger 1. 60. 6. Ravn, J. P. J. Molluskerne i Danmarks Kridtaflejringer. 111. Straligrafiske Undersøgelser. Med 1 Tavle. Résumé en français. 1903 3. 85. XII, med 3 Tavler og 1 Kort. 1902-04 10. 50. 1. Forch, Carl, Knudsen, Martin, und Sørensen, S. P. L, Berichte über die Konstanlenbeslimmungen zur Auf- stellung der hydrographischen Tabellen. Gesanimelt von Mitrlin Knndsen. 1902 .4. 75. 2. Bergh, R. Gasteropoda opisthobranchiala. With three plates and a map. (The Danish expedition to Slam 1899-1900, I.) 1902 3. 45. 3. Petersen, C. 0. Joh., Jensen, Saren, Johansen, ,4. C, og Levinsen, J. Chr. L, De danske Fars'aiides Plankton i Aarene 1898—1901. 1903 ^. 3. 25. 4. Christensen, A. Om Chinaaikaloidernes Dibromadditionsprodukter og om Forbindelser af Alkaloidernes Chlorhydrater med højere Metalcblorider. 1904 1. 35. Zoologiske og anatomiske Skrifter udgivne af Det Kgl. üanske Videnskabernes Selskab (udenfor Skrifternes 6te Række, se Omslagets S. 2—3) : Rr. øre Bergh, R. Bidrag til en Monographi af Marseniaderne, m b Tavler. 53 ... . 4. • Anatoinislte Bidrag til Kundskab om Æolidierne, m. 9 Tavler. 64 5. « Eschrlcht, D. F. AnatomisJi-physioiogiske Undersøgelser over Salperne, m. 6 Tavler. 41 2. 36. Undersøgelser over Hvaldyrene. Afhandling 1 — 6, m. 16 Tavler. 44—48 13. •» Om Gangesdelphinen, m. 3 Tavler. 51 2. » Eschrlcht & Reinhardt. Om Nordhvalen, m. 6 Tavler. RI 4. C.5. Ni Tavler til Oplysning om Hvaldyrenes Bygning m. Forklaring. 69 2. 65. Hannover, A. Mikroskopiske Undersøgelser af Nervesystemet, m. 7 Tavler. 42 3.^« Om Bruskens første Dannelse og Udvikling, m. 2 Tavler. 64 90. Iagttagelser over indkapslede Indvoldsorme hos Frøen, m. 2 Tavler. 65 1. « Epithelioma cylindraceum, foliaceum og globosum, m. 2 Tavler. 65 90. Om Bygningen og Udviklingen af Skjæl og Pigge hos Bruskusk, m. 4 Tavler. 67 2. » Øiets Nethinde, m. 6 Tavler. Explic. des planches en franc. 75 10. • Primordialbrusken og dens Forbening i det menneskelige Kranium fer Fødselen , m. 2 Tavler. Explic. des planches en franc. 80 6. 35. Krabbe, H. Helminthologiske Undersøgelser i Danmark og paa Island, m. 7 Tavler. 65 2. 75. Bidrag til Kundskab om Fuglenes Bændelorme, m. 10 Tavler. Résumé en franc. 69 4. 80. Krøjer, B. Slægten Hippolytes' nordiske Arter, m. 6 Tavler. 42 3. 35. Lütkeu, C. F. Additamenta ad historian! Ophiuridarum. I — 111, m. 7 Tavler. Résumé en franc. 58 — 69 ... 6. 85. — — Bidrag til Kundskab om Arterne af Slægten Cyamus Latr. eller Hvallusene, m. 4 Tavler. Résumé en franc 73. 2. 15 Velhas-Flodens Fiske, et Bidrag til Brasiliens Ichthyologi, m. 6 Tavler. Synopsis Latina. 75 6. 75. Til Kundskab om to arktiske Slægter af Dybhavs- Tudsefiske: Himantolophus og Ceratias, m. 2 Tavler. Résumé en franc. 78 2. ■> Spolia Atlantica. Bidrag til Kundskab om Formforandringer hos Fiske under deres Væxt og Udvikling, m. 5 Tavler. Résumé en franc. 80 8. 20. Meinert, Fr. Bidrag til de danske Myrers Naturhistorie, m. 3 Tavler. 60 2. 25. Presch, V. Nogle nye Cephalopoder, m. 1 Tavle. 47 65. Reinhardt, J. Beskrivelse af nogle nye Slangearter, m. 3 Tavler. 43 1. 60. Mephitis Westermann!, et nyt Stinkdyr fra Brasilien, m. I Tavle. 67 • 65. Bidrag til Kundskab om Kjæmpedovendyret Lestodon armatus. m. 3 Tavler. 75 2. 20. Kæmpedovendyr-Slægten Coelodon, m. 6 Tavler. Résumé en franc. 78 . • 5. • Beskrivelse at Hovedskallen af et Kæmpedovendyr, Grypotherium darwinii, fra La Plata-Landenes plejsto- cene Dannelser, m. 2 Tavler. Résumé en franc. 79 1. 75. Reinhardt & Presch, Om Scidaephorus MüUeri, m. 5 Tavler. 46 2. 25. Scl^edte, J. C. Corotoca og Spirachtha, m. 2 Tavler. 54 t. 35. Steenstrup, Jap. Rhizochilus antipathum, m. 1 Tavle. 53 1. • Hectocotyldannelsen hos Octopodslægterne Argonauta og Tremoctopus, m. 2 Tavler. 66 1. 35. Hemisepius, en ny Slægt af Sepia -Blæksprutternes Familie, med Bemærkninger om Sepia ^ Formerne i Almindelighed, m. 2 Tavler. Resumé en franc. 75 1. 25. Spolia atlantica. Kolossale Blæksprutter fra det nordlige Atlanterhav, m. 4 Tavler. 98 2. 75. Steenstrup & Lütkeu. Bidrag til Kundskab om det aabne Havs Snyltekrebs og Lernæer, m. 15 Tavler. 61. . . 6. » TEKNTW vC ^Jtmnoires de l'Académie Royale des Sciences- et des Lettres de Danemark, Copenhague, 7°"* série, Section des Sciences, l. V, n'-l. V THE DANISH EXPEDITION TO SIAM 1899-1900 V. Brachyura bv Mary J. Rathbun (Washington D. C.) With 2 plates and a map D. Kgl. Danske Vidensk. Selsk. Skrifter, 7. Række, natdhvidensk. og mathem. Afd. V, 4 -fcîHe««»-^ KØBENHAVN HOVEDKOMMISSIONÆR: ANDR. FRED. HØST & SØN, KGL. HOF-BOGHANDEL BIANCO LUNOS BOGTRYKKERI 1910 Pris: 3 Kr. 20 Øre. Det Kgl. Danske Videnskabernes Selskabs Skrifter, 6te Række. NatnrTidenskabelig og matliematisk Afdeling. I, med 42 Tavler, 1880—86 29. 50. 1. Prjl», K. Undersøgelser over Lysets Brydning i Dampe og tilsvarende Vædsker. 1880 • 66. 2. Boas, J. E. V. Studier over Decapodernes Slægtskabsforhold. Med 7 Tavler. Resumé en français. 1880 8. 60. 3. Steenstrup, Jap. Sepiadarium og Idiosepius, to nye Slægter af Sepiernes Familie. Med Itemærkningcr om to beslægtede Former Sepioloidea DOrb. og Spirula Lmk. Med I Tavle. Resumé en français. 1881 1. 35 i. Colding, A. Nogle Undersøgelser over Stormen over Nord- 6g Mellem-Europa af 12'« — li""» Novb. 1872 og over den derved fremkaldte Vandflod i Østersøen. Med 23 Planer og Kort. Resumé en français. 1881 10. • 5. Doas, J. E. V. Um en fossil Zebra-Form fra Brasiliens Campos. Med et Tillæg om lo Arter af Slægten Hippldlon. Med 2 Tavler. 1881 2. • 6. Steen, A. Integration af en lineær DiirerentialligiWng af anden Orden. 1882 60. 7. Krabbe, H. Nye Bidrag til Kundskab om Fuglenes Bændelorme. Med 2 Tavler. 1882 1. 36. 8. Hannover, A. Den menneskelige Hjerneskals Bygning ved Anencephalia og Misdannelsens Forhold til Hjerneskallens Priniordialbrusk. Med 2 Tavler. Extrait et explication des planches en français. 1882 I. 60. 9. Den menneskelige Hjerneskals Bygning ved Cyclopia og Misdannelsens Forhold til Hjerneskallens Priniordialbrusk. Med 3 Tavler. Extrait et explic. des planches en français. ISSi 4. 35. 10. Den menneskelige Hjerneskals Bygning ved Synotia og Misdannelsens Forhold til Hjerneskallens Pri- mordialbrusk. Med 1 Tavle. Extrait et explic. des planches en français. 1884 1. 30. 11. Lehmann, A. Forsøg paa en Forklaring af Synsvinklens Indflydelse paa Opfattelsen af Lys og Farve ved direkte Syn. Med 1 Tavle. Résumé en français 1886 I. 86. II, med 20 Tavler, 1881—86 20. « 1. Wanning, Eug. Familien Podoslemaceae. I»'«' Afhandling. Med 6 Tavler. Résumé et explic. des planches en français. 1881 3. 16. 2. Lorenz, L. Om Metallernes Ledningsevne for Varme og Elektricitet. 1881 I. 30. 3. Wariuing, Eug. Familien Podoslemaceae. 2<'«° Afhandling. Med 9 Tavler. Résumé et explic. des planches en français. 1882 5. 30. 4. Christensen, Odin. Bidrag til Kundskab om Manganets Ilter. 1883 1. 10. 5. Lorenz, L. Farvespredningens Theori. 1883 60. 6. Gram, J. P. Undersøgelser ang. Mængden af Primtal under en given Crænse. Résumé en français. 1884 4. » 7. Lorenz, L. Bestemmelse af Kviksølvsøjlers elektriske Ledningsmodstande i absolut elektromagnetisk Maal. 1885 80. 8. Traustedt, M. P. A. Spolia Atlantlca. Bidrag til Kundskab om Salperne. Med 2 Tavler. Explic. des planches en français. 1885 3. » 9. Bohr, Chr. Om Iltens Afvigelser fra den Boyle-Mariotteske Lov ved lave Tryk. Med 1 Tavle. 1885 ... 1. » 10. • Undersøgelser over den af Blodfarvestoffet optagne Iltmængde udførte ved Hjælp af et nyt Absorptio- nieter. Med 2 Tavler. 1886 ' 1. 70. 11. Thiele, T. N. Om Definitionerne for Tallet, Talarterne og de tallignende Bestemmelser. 1886 2. • III, med 6 Tavler, 1885—86 16. • 1. leulhen, B. 0. Keglesnitslæren i Oldtiden. 1885 ' 10. • 2. Levinsen, G. IQ. R. Spolia Atlantica. Om nogle pelagiske Annulata. Med 1 Tavle. 1885 1. 10. 3. Rung, G. Selvregistrerende meteorologiske Instrumenter. Med 1 Tavle. 1885 1. 10. 4. Meiner!, Fr. De encéphale Myggelarver. Med 4 dobb. Tavler. Résumé et explic. des planches en français. 1886 6. 75. IV, med 26 Tavler. 1886—88 21. 60. 1. Boas, J. E. V. Spolia Atlantica. Bidrag til Pteropodernes Morfologi og Systematik samt til Kundskaben om deres geografiske Udbredelse. Med 8 Tavler. Résumé en français. 1886 10. 60. 2. Lehmann, A. Om Anvendelsen af Middelgradationernes Metode paa Lyssansen. Med 1 Tavle. 1886. ... 1. 50. 3. Hannover, A. Primordialbrusken og dens Forbening i Truncus og Extremiteter hos Mennesket før Fød- selen. Extrait en français. 1887 1. 60. 4. Lutken, Chr. Tillæg til «Bidrag til Kundskab om Arterne af Slægten Cyamus Latr. eller Hvallusene». Med 1 Tavle. Résumé en français. 1887 '. , • 60. 5. Fortsatte Bidrag til Kundskab om de arktiske Dybhavs-Tudsefiske, særligt Slægten Æmantolophus. Med 1 Tavle. Resumé en français. 1887 76. 6. Kritiske Studier over nogle Tandhvaler af Slægterne Tursiops, Orca og Lageiiorhynchus. Med 2 Tavler. Résumé en francais 1887 ! 4 75. 7. Koefoed, E. Studier i Platosoforbindelser. 1888 1. 30. 8. Warming, Eng. Familien Podoslemaceae. 3di« Afhandling. Med 12 Tavler. Résumé et explic. des planches en francals. 1888 6. 45. "V, med 11 Tavler og 1 Kort. 1889—91 . 15. 60. 1. Lutken, Chr. Spolia Atlantica. Bidrag til Kundskab om de tre pelagiske Tandhval-Slægter Steno, Del- phinus og Frodelphimis. Med 1 Tavle og 1 Kort. Résumé en français. 1889 2. 75. 2. Valentiner, B. De endelige Transformations-Cruppers Theori. Résumé en français. 1889 5. 50 3. Hansen, H. J. Cirolanidæ et familiæ nonnullæ propinquæ Musei Hauniensis. Et Bidrag til Kundskaben om nogle Familier af isopode Krebsdyr. Med 10 Kobbertavler. Résumé en français. 1890 9 50. 4. Lorenz, L. Analytiske Undersøgelser over Primtalmængderne. 1891 • 75. (Fortsættes paa Omslagets S. 3.) (Forts, fra Omslagets S. i.) Kr. 01« "VI, med 4 Tavler. 1890—92 13. 75. 1. Loreni, L. Lysbevægelsen i og uden for en af plane Lysbelger belyst Kugle. 1890 2. • Î. Sareiisen, ffllllaiii. Om Forbeninger i Svemmeblæren, Pleura og Aortas Væg og Sammensmeltningen deraf med Hvirvelsøjlen særlig lios Siluroiderne, samt de saakaldle Weberske Knoglers Morfologi. Med 3 Tavler. Késumé en français. 1890 3. 80. 3. Wariulng, Eug. Lagoa Santa. Et Bidrag til den biologiske PlantegeograQ. Med en Fortegnelse over Lagoa Santas Hvirveldyr. Mod 43 Illustrationer i Texten og 1 Tavle. Résumé en français. 1892 10. 85. VII, med 4 Tavler. 1890-94 13. 75. t. Graiu, J. P. Studier over nogle numeriske Funktioner. Resumé en français. 1890 1. |o. 2. Pr;tz, K. Methoder til korte Tiders, særlig Rotationstiders, Udmaaling. En experimental Undersøgelse. Med 16 Fisurer i Te.\ten. 1890 1. 50. 3. Petersen, Eitiil. um nogle Grnndstolfeis ätiotrope Tilstandsformer. 1891 1. 60. 4. Wanning, Eug. Familien Podostemaceae. 4''« Afhandling. Med c. 185 mest af Forfatteren tegnede Figurer i 34 (irupper. Résumé et explication des ligures en français. 1891 1. 50. 5. Christensen, Udhi T. Hhodanchromammonlakforbindelser. (Bidrag til Chromammoniakforbindelser^es Kemi. III.) 1891 : I. 25. 6. Luiken, Chr. Spolia Atlantica. Scopelini Musei Zoologie! Universilatis Hauniensis. Bidrag til Kundskab om det aabne Havs Laxesild eller Scopeliner. Med 3 Tavler. Résumé en français. 1892 3. 50. 7. Petersen, Emil. Om den elektrolytiske Dissociationsvarme af nogle Syrer. 1892 1. 25. 8. Petersen, O.G. Bidrag til Scitamineernes Anatomi. Résumé en français. 1893 2. 75. 9. Lutken, Chr. Andet Tillæg til -Bidrag til Kundskab om Arterne af Slægten Gyanms Latr. eller Hval- lusene». Med 1 Tavle. Résumé en français. 1893 85. 10. Petersen, Emil. Reaktionshastigheden ved Methylætherdannelsen. 1894 I. 50. VIII, med 3 Tavler. 1895—98 12. 25. 1. Meinert, F. Sideorganerne hos Scarabæ- Larverne. Les organes latéraux des larves des Scarabës. Med 3 Tavler. Resumé et explication des planches en français. 1895 3. 30. 2. Petersen, Emil. Damptryksformindskelsen af Methylalkohol. 1896 I. • â Buchwaldt, F. En mathematisk Undersøgelse af, hvorvidt Vædsker og deres Dampe kunne have en fælles Tilstandsligning, baseret paa en kortfattet Fremstilling af Varmetheoriens Hovedsætninger. Résumé en français. 1896 2. 25. 4. Warming, Eug. Halofyt-Studier. 1897 3. • 5. Johannsen, W. Studier over Planternes periodiske Livsyttringer. I. Om antagonistiske Virksomheder i Stofskiftet, særlig under Modning og Hvile. 1S97 3. 75. 6. Nielsen, N. Undersøgelser over reciproke Potenssummer og deres Anvendelse paa Rækker og Integraler. 1898. 1 60. IX, med 17 Tavler. 1898 — 1901 17. . 1. Steenstrup, Japetus, og Lutken, Chr. Spolia Atlantica. Bidrag til Kundskab om Klump- eller Maaneflskene (Molidæ). Med 4 Tavler og en I)el Xylografier og Fotogravurer. 1898 4. 75. 2. Warming, Eug. Familien Podostemaceae. .5'« Afhandling. Med 42 Figurgrupper. Résumé en français. 1899 1. 60. 3. Mejer , Kirstine. Om overensstemmende Tilstande hos StolTerne. En med Videnskabernes Selskabs Guld- medaille belønnet Prisafhandling. Med en Tavle. 1899 2. 60. 4. Jsrgensen, S. IH. Om Zeise's Platosemiætliylen- og Cossa's Platosemiamminsalte. Med 1 Tavle. 1900 . . »75. 5. Christensen, A. Om Overbromider af Chinaalkaloider. 1900 1. • 6. Steenstrup, Japetus. Heteroteuthis irray, med Bemærkninger om Rossia-Sepiola-Familien i Almindelighed. Med en Tavle. 1900 90. Gram, Bille. Om Proteinkornene hos oliegivende Frø. Med 4 Tavler. Resumé en français. 1901 .... 2. 50. 8. Meinert, Fr. Vandkalvelarverne (Lurvæ Dytiscidarwm). Med 6 Tavler. Résumé en francals. 1901 . . 5. 35. X, med 4 Tavler. 1899—1902 10. 50. 1. Juel, C. Indledning i Læren om de grafiske Kurver. Résumé en français. 1899 2. 80. 2. Billmann. Einar. Hidrag til de organiske Kvægsølvforbindelsers Kemi. 1901 I. 80. 3. Samsse Lund og Rostrup, Ë. Marktidselen (Cirsium arvensej. En Monografi. Med 4 Tavler. Résumé en français. 1901 6. ■ 4. Christensen, A. Om Bromderivater af Chinaalkaloiderne og om de gennem disse dannede brintfattigere For- bindelser. 1902 1. 40. XI, med to Tavler og 1 Kort. 1901-03 15. 05. 1. Warming, Eng. Familien Podostemaceæ. 6'« Afhandling. Med 47 Figurgrupper. Résumé en francals. 1901. 2. 15. 2. Ravn, J. P. J. Molluskerne i Danmarks Kridtaflejringer. I. Lamellibranchiater. Med 1 Kort og 4 Tavler. 1902. 4. • 3. Winther, Chr. Rotationsdispersionen hos de spontant aktive Stoffer. 1902 2. • 4. Ravn, J. P. J. Molluskeriie i Danmarks Kridtaflejringer. II. Scaphopoder, Gastropoder og Cephalopoder. Med 5 Tavler. 1902 .- 3. 40. 5. Winther, Chr. Pohirimetriske Undersøgelser 11: Rotationsdispersionen i Opløsninger 1. 60. 6. Ravn, J. P. J. Molluskerne i Danmarks Kridtaflejringer. III. StratigraGske Undersøgelser. Med 1 Tavle. Résumé en français. 1903 3. 8S. XII, med 3 Tavler og 1 Kort. 1902-04 10. 50. 1. Forch, Carl, Knudsen, Martin, und Sorensen, S. P. L. Berichte über die Konstantenbestimmungen zur Auf- stellung der hydiügrapliischen Tabellen. Gesammelt von Martin Knudsen. 1902 4. 75. 2. Bergh, R. Gasteropoda opislhobranchiala. With three plates and a map. (The Danish expedition to Slam 1899-1900, I.) 1902 3. 45. 3. Petersen, C. G. Job., Jensen, Seren, Johansen, A.C., og Levinsen. J. Chr. L. De danske Farvandes Plankton i Aarene 1898—1901. 1903 3. 25. 4. Christensen, A. Om Chinaaikaloidernes Dibromadditionsprodukter og om Forbindelser af Alkaloidernes Chiorhydrater med bejere Metalcblorider. 1904 t. 1. 35. Zoologiske og anatomiske Skrifter udgivne af Det Kgl. Danske Videnskabernes Selskab (udenfor Skrifternes 6te Række, se Omslagets S. 2—3) : Kr. Øre Bergh, R. Bidrag til en Monographi af Marseniaderne, m. 5 Tavler. 53 4. • Anatomiske Bidrag til Kundskab om Æolidierne, m. 9 Tavler. 64 ... . •.' 5. • v,i ■■).■ ËKhrlcht, D. F. Anatcmisk-physiologiske Undersøgelser over Salperne, m. 6 Tavier. 41 2. 35 Undersøgelser over Hvaldyrene. Afhandling 1 — 6. m. 16 Tavler. 44—48 13. » Om Gangesdelphinen, m. 3 Tavler. 51 2. • Eschrlcht 4 Reinhardt. Om Nordhvalen, m. 6 Tavler. 61 . . 4. 65 NI Tavler til Oplysning om Hvaldyrenes Bygning m. Forklaring. 69 2. 65. Hannover, A. Mikroskopiske Undersøgelser af Nervesystemet, m. 7 Tavler. 42 3. • Om Bruskens første Dannelse og Udvikling, m. 2 Tavler. 64 • 90- Iagttagelser over indkapslede Indvoldsorme hos Frøen, m. 2 Tavler. 65 1. • Epithelioma cylindraceum, foliaceum og globosum, m. 2 Tavler. 65 90. Om Bygningen og Udviklingen af Skjæl og Pigge hos Bruskfisk, m. 4 Tavler. 67 2. • Øiets Nethinde, m. 6 Tavler. Explic. des planches en franc. 75 . . . 10. » Primordialbrusken og dens Forbening i det menneskelige Kranium før Fødselen, m. 2 Tavler. Explic. des planches en franc. 80 • . . . 6. 35. Krabbe, H. Helminthologiske Undersøgelser i Danmark og paa Island, m. 7 Tavler. 65 , ■ - 2. 75 Bidrag til Kundskab om Fuglenes Bændelorme, m. 10 Tavler. Résumé en franc. 69 4. 80. Krojer, H. Slægten Hlppolytes' nordiske Arter, m. 6 Tavler. 42 3. 35 Lutken, C. F. Additamenta ad historiam Ophiuridarum. 1— 111, m. 7 Tavler. Résumé en franp. 58—69 ... 6. 85. Bidrag til Kundskab om Arterne af Slægten Cyamus Latr. eller Hvallusene, m. 4 Tavler. Résumé en franc 73. 2. 15 ■ Velhas-Flodens Fiske, et Bidrag til Brasiliens Ichthyologi, m. 5 Tavler. Synopsis Latina. 75 6. 76. Til Kundskab om to arktiske Slægter af Dybhavs -Tudsefiske: Himantolophus og Ceratias, m. 2 Tavler. Résumé en franc. 78 2. • Spolia Atlantica. Bidrag til Kundskab om Formforandringer hos Fiske under deres Væxt og Udvikling, m. 5 Tavler. Résumé en franc. 80 ... 8. 20. Meinert, Fr. Bidrag til de danske Myrers Naturhistorie, m. 3 Tavler. 60 2. 25. Prosch, V. Nogle nye Cephalopoder, m. I Tavle. 47 65. Reinhardt, J. Beskrivelse af nogle nye Slangearter, m. 3 Tavler. 43 t. 50. Mephitis Westermanni, et nyt Stinkdyr fra Brasilien, m 1 Tavle. 57 »65. Bidrag til Kundskab om Kjæmpedovendyret Lestodon armatus. m. 3 Tavler. 75 2. 20. Kæmpedovendyr-Slægten Coelollon, m. S Tavler. Resumé en franc. 78 S. • Beskrivelse af Hovedskallen af et Kæmpedovendyr, Grypotherium darwinii, fra La Plata-Landenes plejsto- cene Dannelser, m. 2 Tavler. Résumé en franc. 79 1. 75. Reinhardt & Prosch. Om Scidaephorus Mülleri, m. 5 Tavler. 46 2. 25. Scljadte, J. C. Corotoca og Spirachtha, m. 2 Tavler. 54 1. 35. Steenstrup, Jap. Rhizochilus antipathum, m. 1 Tavle. 53 1. • Hectocotyldannelsen hos Octopodslægterne Argonauta og Tremoctopus, m. 2 Tavler. 56 1. 35. Hemisepius, en ny Slægt af Sepia - Blæksprutternes Familie, med Bemærkninger om Sepia - Formerne i Almindelighed, m. 2 Tavler. Résumé en franc. 7.i 1. 25. Spolia atlantica. Kolossale Blæksprutter fra det nordlige Atlanterhav, m. 4 Tavler. 98 2. 75. Steenstrup & Lutken. Bidrag til Kundskab om det aabne Havs Snyltekrebs og Lernæer, m. 15 Tavler. 61. . . 5. • ! 1 Lii i;i li i!i, liii 5 WHSE 00016 !.<"• : ,1 .' ^*;^' ■!::;: ;^;;:;Vv J'! Sti •-■■i!'-';:^ V'l •;':v;', :v'-'' ''''/:'■ ■.■;:.:■:;,-,..:'-!■ 1 ■ ' ' I' f ' ■• I ; x; '11:. ; ivir 4';f-r'''-'l:'-!^':'::;i"r,JV^ -..(; ;.: