IX. 

 FAMILY BULINIDAE 



This group has ahnost universally been considered a subfamily of Planor- 

 bidae. It is so treated by Pilsbry (1927, p. 132). More recently several 

 authors have considered the group as of family rank, distinct from the 

 Planorbidae (Germain, 1931, p. 514; Larambergue, 1939). The shell is of 

 Physoid shape but the radula is like that of Planorbis. Two characteristic 

 features of the group separate it from any known division of the Planor- 

 bidae, the fluted or lobular })seudobranch and the shape of the ]ienial com- 

 plex in the genitalia. These are so different that they would appear to be 

 characteristics of family rank. The family is mostly exotic, distributed as 

 far as known in Australia, Oceania, New Guinea, Celebes, Japan, India, 

 the Ethiopian and Malagasy regions, the ^Mediterranean subregion as far 

 east as Mesopotamia, and the Antilles (vide Pilsbry, 1927, p. 132). Only 

 one species occurs in the Antillcan region. 



The present work was prepared to include only the groups i)roperly 

 belonging to the family Planorbidae, but as one species previously referred 

 to the Planorbidae has recently been placed in Bulinidae, space is given 

 to a discussion of this species and the data for its inclusion in a family to 

 which it was not previously believed related. 



Genus INDOPLAXORBIS Aiinandale and Prashad. 1920 

 Type by original designation, Planorbis exustus Deshayes 



1920. Iitdoplanorbis Ann.\nd.\le and Pr.\sh.\d, Jour. Med. Res., VIII, p. 112. Type 



Planorbis exustus Deshayes. As genus 



1921. Indoplanorbis Pr.ash.\d, Rec. Ind. Mus., XXII, p. 471. Tvi)p Planorbis cxuslus 



Desh. As genus 



1921. Indoplanorbis Axn.\ni).\le and Pk.\.shad, Roc. Ind. Mus., XXII, p. 578. Type 

 Planorbis exustus Desh. As genus 



1921. Planorbis (PUmorbis) exustus Germ.mx, Rec. Ind. Mus., XXI, pp. 26-41. Ex- 



haustive account of variation and .synonymy 



1922. Indoplanorbis Anx.and.\le and Pr.\sh.ad, Rec. Ind. Mus., XXIV. p. 360. Type 



Planorbis exustus Desh. As genus 



1923. Indoplanorbis Rao, Rec. Ind. Mus., XXV, pp. 199-219. Tyi)e Planorbis exustus 



Desh. Description of anatomj'. As genus 

 1926. Indoplanorbis Thible, Handbuch, p. 479. T^-pe Planorbis exustus Desh. As 

 section of Planorbis 



1933. Indoplanorbis F. C. B.\ker, Jour. Morph., LV, No. 1, pp. 1-12, phite 1-2. Type 



Platwrbis exustus Desh. Account of anatomy, especially genitalia and radula. 

 As genus 



1934. Indoplanorbis Pilsbry, Proc. Acad. X'at. Sci. Phil., 86, p. 54. Remarks on 



taxonomic position 

 1939. Indoplanorbis exustus Larambergue, Bull. Soc. Zool. de France, LXIV, No. 5, 

 pp. 286-295. Anatomy and family position. As genus 



Shell (plate 79, figs. 33-35). Of medium size, sinistral, with few rapidly 

 increasing whorls, the body whorl large and greatly increasing in diameter 

 toward the aperture; spire whorls flat, depressed below the level of the 

 body whorl; base with small umbilical opening, the inner whorls concealed 

 by the last two whorls; aperture usually oblique, lips simple, sharp. 



Animal (plate 21, fig. 2). 'The animal is sinistral. Its foot is relatively 

 broad and short, leaf-shaped, broadly rounded in front and pointed behind. 



196 



