(With 30 Plates) Together with Mrs. E Veline I Have Passed from Sand

b y E r n e s t o M a r c u s (with 30 plates) Together with Mrs. E v e l in e d u B o is -R e y m o n d M a r c u s I have passed from sand-dwelling to other marine Euthyneura, con ventionally called Opisithobranchia. While our modern bibliography is rather complete, thanks to many Colleagues who kindly helped us with separate copies, that of the first half of the past century as well as Trinche£e’s (see Eliot’s note, 1910b, p. 189) is hopelessly incomplete. Papers from the classic period of investigation of ma rine Euthyneura, connected with the names of Alder & Hancock, Bergh, Eliot, and Vayssière, were obtained gradually during the ela boration of this study Therefore they were considered unequally and we hope to supply present bibliographic gaps in future publi cations. Especially the “Malacclogische Untersuchungen” of Bergh were only received after the completion of the present Ms. through Dr. Sebastian Adam Gerlach-Kiel, who kindly photocopied them for us. To Dr. Erich Schulz we are indepted for a photocopy of Rang’s monograph of the Aplysiae with the plates primorously re produced in colours. This precious gift is of great value for our studies on this family The material was obtained in the upper littoral chiefly of the State of São Paulo. One of our colecting trips was supported by a grant from the National Research Council (Conselho Nacional de Pesquisas) in Rio de Janeiro. The animals were narcotized after Pantin (1948, p. 6 , “N ar cotics” b) and fixed with “Susa” (ibid., p. 8 ). For the preservation of shells and spicules alcohol 90% was used. The reproductive or gans and other anatomical details were mostly reconstructed from transverse sections; sometimes animals were also dissected. The following list of the species treated in this paper aims at a rapid, moderately modern orientation, not at the establishment of taxonomically équivalente units. Cephalaspidea and Anaspidea, f.. ex., are separated as independent orders by Odhner (1939, p. 4), while all Doridacea are united in one suborder (ibid., p. 25) Tectibranchia ( Pleuroccela ) Cephalaspidea, Bullariidae: Bulla striata Brug. Cephalaspidea, Aglaiidae: Chelidonura evelinae, sp. n. Anaspidea, Aplysiidae, Notarchinae: Bursatella leachii laci- nulata Gould Anaspidea, Aplysiidae, Notarchinae: Bursatella leachii pleii (R ang) Anaspidea, Aplysiidae, Dolabriferinae: Phyllaplysia engeli, sp. n. Sacoglossa, Elysiacea Hermaeidae: Hermaea coirala, sp. n. Elysiidae: Elysia canguzua, sp. n. Elysiidae: Elysia serca, sp. n. Elysiidae: Elysia chitwa, sp. n. Notaspidea, Pleürobranchacea Pleurobranchidae: Berthella agaieizii (MacFarl.) Nudibranchia, Doridacea, Eudoridacea, Cryptobranchia, Dorididae: Glossodoridinae: Cadlina rumia, sp. n. Glossodoridinae: Glossodoris neona, sp. n. Doridinae: Doris verrucosa Cuv. Doridinae: Doris bovena, sp. n. Doridinae: Siraius ilo, g. n., sp. n. Discodoridinae: Peltodoris greeleyi M acFarL Discodoridinae: Thordisa diuda, sp. n. Discodoridinae: Divcodoris evelinae, sp. n. Discodoridinae: Discodoris pusae, sp. n. Discodoridinae: Taringa telopia, g. n., sp. n. Centrodoridinae: Awuka spazzola, g. n., sp. n.. Nudibranchia, Doridacea, Eudoridacea,. Phanerobranchia Nonsuctoria, Polyceridae: Polycera odhneri, sp. n. Suctoria, Goniodorididae: Goniodoris mimula, sp. n. Suctoria, Corambidae: Corambella carambola, sp. n. Nudibranchia, Dendronotacea Dotonidae: Doto uva, sp. n. Dotonidae: Doto pita, sp. n. Nudibranchia, Aiminacea, Pachygnatha Antiopellidae: Janolus comis, sp. n. Nudibranchia, Eolidacea, Acleioprocta Cuthonidae: Catriona ccerulea (M tg.) Cuthonidae: Piseinotecus divae, g. n., sp. n. Nudibranchia, Eolidacea, Cleioprocta Facelinidae, Facelininae: Phidiana selenkai Bergh Facelinidae, Favorininae: Favorinus auritului., sp. n. Aeolidiidae: Spurilla neapolitana braziliana M acFarl. Bulla striata Bruguiere (Fig. 1-7) The systematically important characters are described in the· following for a population collected on an about 6 km. long tract of the beach. Some young living animals are included (Fig. 1) The profile of young and adult shells (Fig. 1, 2) is characte rized by a nearly straight right and a convex left border The shell is distinctly narrower above than below, the greatest breadth lies a little below the middle. The outer border stands out over the apex that has a deeply sunken spire. The high and narrow aper ture widens to a broad oval below the middle of the shell. The ou ter lip is sharp and in the pauses of growth thickened. The colu mella is not quite straight and ends approached to the left side. There are 8 whorls in adult shells. Besides the lines of growth, the distinctness and breadth of which varies widely, there are fine longitudinal striae and spiral lines inside the apical cavity. The number of the latter, 0-8, is not correlated with the size of the shells. The transverse apical (poste rior) striae on the surface of the last formed whorl are rarely as distinct as in Hoffmann’s figure (1934, f. 254 D) Sometimes they are vestigial, and in many cases absent. The corresponding striae cf the inferior cr anterior part are constant, as Si (1931, p. 31) stressed. The colour cf the shells is creamy, light brown or dark grayish yellow indistinctly mottled with all shades from light brown to black. The inner surface and the inner lip are white. The fleshy parts of adult animals are dark yellowish gray to black, those cf young snails light gray Greatest diameter and total length (Aguayo & Jaume 1944, p. 45, t. 7, f. 2, 4) were measured in 150 shells, the length of which varied from 14 to 37,8 mm. The latter, our largest shell, has a greatest diameter of 21,6 mm. Its proportion between dia meter and length is 1:1,75. This corresponds approximately to *he medium proportion between diameter and length in our po pulation, 1:1,70. The variation cf this proportion in the present .material ranges from 1:1,53 to 1:1,90. The proportions of 10 shells from the brazilian coast about 350 km. farther sou'.hwest (Gcfferje 1950, p. 221, 251) lie within these limits, though their absolute measurements are considerably smaller. The Figures 5-7 show the larval shell of an about 30 mm. long specimen (Fig. 2), from the eighth whorl of which it was freed. The larval spire is directed downwards. The angle bet ween the axis cf the helicoid larval shell and that of the adult one is about 45° The larval shell is transparent and colourles:. Its diameter is 0,22 mm. and its height 0,2 mm. The number of whorls is about 1,7 The initial chamber that is slightly elevated likens that of Diaphana hyalina (Thorson 1946, fig. 147A; after Lemche 1948, p. 74 = Diaphana minuta Brown 1827) and thast of Philine aperta (Thorson, fig. 150 H ) . The last part of the outer whorl partly overlaps the initial chamber and the first whorl. The radulae of the present material (Fig. 3) contain 26-27 series of plates. The median plate has a small central denticle and 5-7 larger ones on each side. The first lateral or intermedia te plate has a big central denticle and 2-5 smaller lateral ones on each side. The following lateral plate has 6-8 denticles on its outer side. The third or marginal plate is small and has no den ticles . Various aspects of the three plates of the gizzard are drawn in Fig. 4. Occurrence: Island of São Sebastião, many hundreds of shells on the beach in november 1953 and april 1954, partly empty, partly still containing the dried soft parts. Five young living specimens with 2,7 to 6 mm. long shells among algae on boulders in the littoral, 4 in november and one in april. Discussion of Bulla striata Brug. The characters of the shell and the radula of the present material agree in general lines with Vayssière’s description of mediterranean specimens of B. striata (1885, p. 14-17). In the brazilian snails, however, the rhachidian plate is proportionally bigger than in those from Naples (Vayssière, 1. c.). Therefore the name striata is here applied with a slight reserve, in as much as even the name of the mediterranean species seems to be not en tirely settled (Pruvot-Fol 1933, p. 92, note 3). One can certainly net unite our animals with B. occidentalis (A. Adams) after Lo- card’s discrimination between the latter and striata (1897, p. 51- 52) Zoogeographically B. occidentalis appears more probable to occur on the coast of Brazil than the mediterranean and east atlantic striata. But even a distribution of one species on both si des of the Atlantic can not be rejected for a Tectibranch, the dis tinct larval shell of which, with regular whorls, indicates a pela gic larval life (Thorson 1946, p. 246; Lemche 1948, p. 25-26) During their pelagic life Tectibranch larvae feed and grow vigo rously (Thorson, p. 436) Both authors (Thorson, p. 466-467; Lemche, p. 11) explain with good reasons “that deep-water spe cimens in the north Atlantic originate from drift-larvae which have been carried from the shallow-watered coast areas to the • deep-sea, where, in lack of a suitable substratum, they have post poned their metamorphosis and continued their mid water life”, until they finally are forced to metamorphose. It is doubtful whether the larvae produced by adult animals in the deep-sea find sufficient food (Lemche, 1. c.), but one can suppose that so me of them reach the surface by vertical currents and are able to continue transatlantic spreading of the species. The reproductive organs and the range of variation of the radulae in Bulla are not sufficiently known for systematic pur poses. Perhaps the protoconch can furnish systematic criteria. A future more detailed examination should also consider B. rubigi- no a (Gould 1852, p. 221; 1856, t. 15 f. 266 a. b) Ihering (1915, p.

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