APPENDIX. 



I 



The following extracts from a letter recently received from 

 ray esteemed correspondent, Dr. James Lewis, who has devoted 

 ranch time to the study of the Melanians, possess great interest 

 in connection with the uncertainty which pervades the S3'non- 

 ymy of the family. Dr. Lewis is well known to conchologists 

 as an acute observer and philosophical naturalist, and his 

 opinions and suggestions are correspondingly valuable. 



G. ^Y. T., Jr. 



Mohawk, N. Y., Aug. 15, 1873. 

 Mr. Tnvox, 



Deau Sir: 

 ************ 



I do not consider Goniobasis castnnca to be the same as G. simplex. 

 It is more likely (if possible) that simplex covers shells that have been 

 named to me by correspondents G. alerina, Lea, G. graminea, Hald., 

 etc. Probably Ilaldcman was right when he thouglit G. acuto-carinata, 

 Lea, was a variety of simplex. I suspect that it is so for the reason 

 that in tlic two (contiguous) localities from which I have acuto-carinata 

 it occurs associated with species which, in nearly every other station, 

 are living with moUusks that have been variously referred to aterina. 

 Lea, and graminea, Hald. And as this association of similar types 

 with a certain group of species extends over a large area each side of 

 the Ilolston River, from Jefferson County southwest to Roane Countj', 

 it seems to me to indicate that the varying forms, of which alerina Vind 

 acxito-carinata are types, are simply one species, varied somewhat con- 

 spicuously in size and perfection of development, and still more varied 

 in degree of carination of the upper wliorls, while tlic texture and 

 color ot the epidermis and of the shells are less varied than niiglit be 

 expected. 



The same mode of reasoning that would fit aterina, graminea, acuto- 

 carinata, etc., and refer them to simplex, would make a unit of all the 

 various shells I refer to castanea, including a large mass of unreduced 

 synonymy in which, perhaps, G. glabra. Lea, may be a leading term. 

 Of this last, however, I have yet to assure myself. You will observe, 



(4L>3) 



