460 Bulletin American Museum of Natural History [Vol. LIIT 
should not be forgotten that all these regions have been in steady con- 
nection by native craft for several thousands of years.! As pointed out 
by Mr. H. Lang, stumps and leaves of bananas are continually trans- 
ported by the Congo natives, either to start new cultures or as wrapping 
material; young shells and mollusk eggs may easily keep alive in them 
for weeks. In East Africa a number of species of snails have been 
described from specimens found in stored seeds. 
One of the most interesting examples of a snail that has been very 
widely scattered by man is Opeas gracile (Hutton), the present distribu- 
tion of which is shown on Map 7. It is now commonly found throughout 
southern Mexico, Central America, the West Indies, northern South 
America, and the Indo-Malayan Region. In addition it has been re- 
ported from Mobile in Alabama, several places in Brazil, southern Japan, 
several of the Polynesian islands, Mauritius, northern Madagascar, 
Aden, Suez, and Djeddah on the Red Sea, Jalk in Persia, and Tuakungu 
and Malela in tropical Africa. It has also been observed in greenhouses 
in England. The species is now so well established both in the East 
Indies and in tropical America that it is impossible to decide whether 
its original home was the Old or the New World.® 
Care should also be taken not to trust unreservedly records based 
upon dead specimens obtained from regions where the species may no 
longer be found living or may never have lived at all. Especially at the 
northern limit of the Ethiopian Region the gradual drying up of the 
country has without doubt caused certain species or even genera to 
become extinct within comparatively recent times. Thus, the map of 
the present distribution of Limzcolaria published in the report of Congo 
land mollusks' was based exclusively upon records of specimens presum- 
ably found alive. The northern limit of the genus was therefore drawn 
much farther south than on similar maps recently published by Germain.® 
We do not deny the possibility of Limzcolaria still living in the Sudan 
north of the sixteenth northern parallel, but in our opinion the avail- 
able evidence is not convincing. The locality records cited by Germain 
1H. H. Godwin-Austen. 1908. ‘The dispersal of land shells by the agency of man.’ Proc. Malacol. 
Soc. London, VIII, pp. 146-147. E. E. Green. 1911. ‘The wanderings of a gigantic African snail.’ 
Zoologist, (4) XV, pp. 41-45, Pl. (see also 1910, Spolia Zeylanica, VII, p. 56). G. C. Robson, 1914, 
Journ. Linn. Soc. London, Zool., XXXII, p. 377. Germain, 1921, ‘Faune Malacol. Terr. Fluv. Iles 
Mascareignes,’ pp. 188-189. 
21919, Bull. American Mus. Nat. Hist., XL, pp. 55-56. 
_ 3Compare the accompanying map of Opeas gracile with that given by Germain (1920, ‘ Voy. Afrique 
Orientale Anglaise G. Babault, Moll. Terr. et Fluv.,’ p. 121, fig. 9) for Subulina octona (Brugierére). 
Dupuis and Putzeys have recently described from Boma, in the Lower Congo, Cecilioides spencei (1922, 
Ann. Soc. Zool. Belgique, LITT, 1, p. 48, fig. 2). From the description this appears to be C. gundlachi 
Pfeiffer, a snail originally from the Antilles, but now widely scattered by man (Philippines, Hawaiian 
Islands, New Caledonia, etc.) and therefore several times renamed. 
41919, Bull. American Mus. Nat. Hist., XL, p. 91. 
51920, ‘ Voyage Afrique Orient. Anglaise G. Babault, Moll. Terr. Fluv.,’ p. 81, fig. 6; 1920, Bull. 
Mus. Hist. Nat. Paris, pp. 527-533. 
