90 The Molhiscan Family Planorbidae 



the genus Planorbis. In a later publication (1934, p. 55) this relationship 

 is again emphasized. In both references by Pilsbry the suggestion is made 

 that the shell might have been modified somewhat after the manner of 

 Taphius. The shells as figured by Pilsbry (1927, p. 121, reproduced on plate 

 81 of this work) are strongly suggestive of Taphius, and Biomphalaria 

 might bear the same relationship to Ajroplanorhis that Taphius bears to 

 Tropicorbis. Its best place in classification at present appears to be near 

 Afroplanorbis as a distinct genus. 



Genus AUSTRALORBIS Pilsbry, 1934 



Type by original designation Planorbis guadaloupensis 

 Sowb. = Planorbis glabratus Say 



1883. Menetus Flscher, Man. de Conch., p. 509. Type PI. guadaloupensis Sowb. 

 (non H. and A. Adams, 1855). As section of Planorbis 



1899. Menetus Martens, Biol. Cent. Amer., Moll., p. 390 (non H. and A. Adams, 

 1855). Martens gives no type but says subgenus is peculiar to South America 

 and mentions Planorbis cumingia7ius Dkr., and Planorbis guadaloupensis 

 Sowb. as examples 



1905. Planorbina Dall, Alaska Moll., pp. 81, 84. Type by original designation P/a«or£)is 

 olivaceus Spix (non Planorbina Haldeman, 1843). As section of Planorbis 



1918. Planorbina Walker, Miscel. Pub. Mus. Zool., Univ. Mich., Xo. 6, pp. 11, 94. 

 Type Planorbis olivaceus Spix (non Planorbina Hald, 1843). As section of 

 Planorbis 



1921. Planorbina Germain, Rec. Ind. Mus., XXI, pp. 6, 41. Type Planorbis guadalou- 

 pensis Sowb. (non Planorbina Haldeman, 1843). As subgenus of Planorbis 



1923. Planorbina Wenz, Fossil. Cat., pars 22, p. 1482. Genotype Planorbis guadalou- 

 pensis Sowb. (non Planorbina Haldeman, 1843). As genus and subgenus 



1930. Planorbina H. B. Baker, Oc. Papers, Mus. Zool., Univ. Mich., No. 210, p. 43. 



Type Planorbis olivaceus Spix (non Planorbina Haldeman, 1843). As genus 



1931. Planorbina Thiele, Handbuch, Teil 2, p. 480. Type Planorbis olivaceus Spix 



(non Planorbina Haldeman, 1843). As section of Planorbis 

 1934. Australorbis Pilsbry, Proc. Acad. Nat. Sci. Phil., 86, p. 55. Type Plaiiorbis 



guadaloupensis Sowh. (^ Planorbis glabratus Say). As genus 

 1938. Australorbis Martins, Contribuicao ao estudo do genero Australorbis Pilsbry, 



1934. On p. 47 lists Brazilian species of this and other genera. Some of the 



species listed belong to Tropicorbis 

 1940. Australorbis Scott, Xotulae Naturae, No. 54, p. 9. As genus. 



Shell (plate 77, figs. 29-31, Australorbis glabratus (Say) ). Large, bi- 

 concave, smoothish, of slowly widening whorls which are rounded or 

 angular laterally (Pilsbry, p. 55). The shell is sinistral. 



Animal. Resembling Tropicorbis in general form. The color is grayish 

 or blackish, the mantle mottled with brown or cinnamon. 



ANATOMICAL CHARACTERISTICS 

 PLATE 9 {Australorbis glabratus) 



GENITALIA. Male Organs (fig. 10) . The seminal vesicle (SV) is 3 mm. 

 long and is an enlargement of the ovisperm duct on which there are many 

 elongated follicles placed laterally. For a distance of 2 mm. behind and 4 

 mm. in front of the seminal vesicle there are numerous nodes which are 

 probably continuations of the seminal vesicle. The sperm duct (SPD) is a 

 very long and narrow tube (29 mm. long) of the same caliber throughout. 

 The prostate is 8 mm. long and is composed of twenty-three or twenty-four 

 diverticula, the two or three anterior diverticula single and unbranched 

 and the three posterior diverticula bifurcate. The others, eighteen in num- 



