620 



PROCEEDINGS OF THE ACADEMY OF 



[Dec, 



River and Itacoatiara, leaving in the first subdistrict Maranhao, 

 Para, and all points on the lower Amazon and its tributaries up to, 

 and including, the Tapajoz and including in the second subdistrict 

 Itacoatiara on the Amazon and all of the Madeira River and its 

 tributaries. 



The shells here reported represent 43 genera, 93 species, and 20 

 subspecies, of which 33 species and 12 subspecies seem to be new. 



The types of all of the species and subspecies are deposited in the 

 collection of the Academy of Natural Sciences of Philadelphia, and 

 cotypes of many of them will be deposited in the collection of the 

 Leland Stanford Jr. University at Palo Alto, California, and in the 

 Museu Goeldi at Para, Brazil. 



In the following list, the species and subspecies are considered 

 with reference to the three districts herein marked out, column 

 one representing the first district, including Rio Grande do Norte 

 and Ceara; column two representing the second district, extending 

 from Maranhao to the Rio Tapajoz and its tributaries, and column 

 three representing the third district, including Itacoatiara and the 

 whole of the Madeira River System. 



Index of Species and Subspecies with General Locations. 



Species and Subspecies. 



Ampullaria bridgesii Rve 



" crassa Swains 



" figulina Spix 



" ffigas Spix 



" insularum Orb 



" lineata Spix '... 



" nobilis Rve 



" peristomata Orb 



" testudinea Rve 



Anodontites bartschi n. sp 



" dalli n. sp 



" ensiformis Spix 



" trapesialis anserinus Spix 



Anostoma depressum Lam 



" octodentatmn F. de Wald 



Bifidaria servilis Gld 



Bulimulus erectus Rve , 



" pubescens Moric 



" rochai n. sp 



" " suturalis n. subsp.... 



" " taipuensis n. subsp.. 



" tenuissimus Orb , 



Coecilioides gundlachi Pfr 



Castalia ambigua Lam 



" quadrilatera Orb 



12 3 



XXX 



X 

 X X 



X X 



X X 

 X X 



X 

 ...:. X X 



X X 



X 



X 

 X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



XXX 

 X 



X X 



X 



Page. 



660 

 659 

 659 

 659 

 660 

 660 



668 

 667 

 667 

 667 

 643 

 644 

 646 

 635 

 635 

 636 

 637 

 636 

 635 

 646 



