BOTHRIKMBUYON, 1'LACOSlVLt S. H 



shows a pallial system somewhat unlike known American Bull mull, in 

 the partial rotation of the pericardium and kidney. A tendency 

 toward that condition exists however in some forms of Drymseus. I 

 regret that want of material prevents a new examination of the pallial 

 organs and retractor muscles. 



Bothriembryon inhabits South Australia and Western Australia, 

 with a single species in Tasmania. 



B. dux Pfr., xiii, 3. B. physodes Mke., xiii, 234. 



B. inflatus Lam., xiii, 3. physoidcs Reeve., xiii, 9. 



? costulata Fer. B. brazieri Ang., xiii, 10. 



me/ones Fer. v. humilis Pils., xiii, 10. 



ovum Dh. B. gratwicki Cox, xiii, IT. 



v. melo Q. G., xiii, 5. B. onslowi Cox, xiii, 11. 



v. castaneus Dh., xiii, 5. v. minor Pils., xiii, 12. 



v. maculiferus Pils., xiii, 5. hartogensis Kobelt, xiv, 166. 



v. conispira Pils., xiii, 5. B. leeuwinensis 8m., xiii, 13. 



B. rnartensi Kob., xiv, 166. B. indutus Mke., xiii, 13. 



B. spenceri Tate, xiii, 6. ? rhodostoma Gray. 



B. kingii Gray, xiii, 7. v. pallidus Tate, xiii. 15. 



trilineata Q. G. B. bulla Mke., xiii, 15. 



sayi Pfr. B. baconi Bens., xiii, 16. 



quoyi Cox. B. angasianus Pfr., xiii, 16. 



v. solidus Pils., xiii, 9. B. masters! Cox, xiii, 17. 



v. naturalistarum Kob., B. gun.ni Sowb., xiii, 18. 



Conch. Cab., p. 781. tasmanicus Pfr. 



v. maxwelli 4 Braz./ Kob. v. brachysoma Pils., xiii, 19. 



Genus PLACOSTYLUS Beck, 1837. 



Manual XIII, p. 19. Type P.fbratus Marty n. 



Chiefly large shells, the ground living species brown, often thick 

 and ponderous, the arboreal species thinner and frequently variegated 

 with green or white. Nepionic whorls thimble-punctate when un- 

 worn. Aperture and lip commonly orange-red. 



The kidney (in P. shongii, pi. 51, fig. 15) is short and triangular, 

 as long as the pericardium, with closed ureter and gut-ureter. The 

 heart lies obliquely to the long axis of the lung. The capacious pul- 

 monary vein bears no large branches. The first branch of the 

 pericardial vein arises close to its origin, and is almost as conspicuous 

 as the pulmonary vein, from which it is separated by the very long 



