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which the shell differs remarkably in its plan of convolution. In no part 

 of the American continent is the theory of specific centres of creation, ad- 

 vocated by Professor E. Forbes, so distinctly recognized as in this area of 

 ten degrees. On the Corcovado and other lofty mountains in the vicinity 

 of Rio, in dense woods at an elevation of 1,000 to 1,500 feet, is a singular 

 group, B. Pantagruelinus, exesus, odontostoma, Pupoides, etc., of which 

 the shell differs from all other types of the New World, in having a num- 

 ber of tooth-like processes developed within the aperture of the last whorl 

 on arriving at maturity. The only country in which this character again 

 appears is in the centre of the Old World, among the smaller and more 

 temperate species of Syria and Hindoostan. In this part of Brazil we 

 have also another type, peculiar to the locality, in which the last whorl is 

 produced in front into a longitudinally angled channel, as in B. goniostoma, 

 egregius, angulatus, fusiformis, etc. Upon the leaves of damp underwood, 

 at an elevation of about 2,000 feet, is another distinct and brilliantly co- 

 loured group, B. multicolor, Miersii, and the large B. ovatus, which in- 

 habits also the neighbouring island of St. Catharina. In the lower grounds 

 upon orange-trees and in the coffee plantations about Tejuca at 1,000 feet 

 above the sea-level, the Bullml, as in the lower parts of Venezuela, have 

 their shells characteristic of less moisture and fewer opportunities of re- 

 tirement. B. papyraceus may be quoted as an example. The more lofty 

 and thickly wooded parts of Minas Geraes produce a type with shells of 

 solid growth and intertropical brilliancy of colour, represented by B. Mil- 

 leri, bilabiatus, planidens, melanostoma, etc. In the vicinity of Bahia is a 

 group with shells of totally different construction and of lighter substance, 

 B. navicula, auris-leporis, etc., in which the last whorl is convoluted trans- 

 versely, at a right angle with the axis of the spire. Lastly, at Caravelhas, 

 below Bahia, and at the little island of Coxaprego, at the mouth of the 

 Iguaripe river, is a remarkable type, represented by B. calcareus, obeliscus, 

 sylvaticus, etc., of which the shell, presenting a singular contrast with the 

 preceding group, is composed of a large number of whorls, drawn out into 

 the elongated form of a Turritella. This partial grouping of opposite 

 forms, within a comparatively limited area having few natural boundaries, 

 will doubtless become broken up to a certain extent with the spread of 

 human population. Already have the climate and natural vegetation of 

 Rio been modified by the clearing away of the neighbouring forests of the 

 Corcovado range of hills, which tends to reduce the humidity and other 

 circumstances that combine to favour the growth and calcification of the 

 terrestrial mollusca. 



Owing probably to the recent geological disturbances that are supposed 

 by Lyell, Darwin, and others to have taken place in the southern extre- 

 mity of the American continent, there are no typical provinces of Bulimi 

 below Rio. The genus is represented by one or two scattered species in 



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