288 ORTMANN— CORRELATION OF SHAPE AND 



general results, and to support them by tables of measurements. 

 The material of this species is rather rich, and I shall not give the 

 measurements of all of it, but shall restrict myself to selected 

 examples which show the law clearly. 

 I have distinguished here three forms. 



1. FuscoNAiA BARNESiANA (Lea). — Dia. 40-49 per cent. 



2. FuscoNAiA BARNESIANA BiGBYENSis (Lea). — Dia. less than 

 40 per cent. 



3. FuscoNAiA BARNESIANA TUMESCENS (Lea). — Dia. 30 per 

 cent, or over. 



I first give the material from three large rivers in the vicinity 

 of Knoxville. 



Loc. No. Max. Min. Av. 



Tennessee River, Little R. Shoals. i 57 57 57 tuni. 



Little Tenn. River, Monroe Co. ..3 57 51 54 turn. 

 French Broad River, Boyd Creek. 5 55 45 50 turn, (barn.) 



Holston River. 



Mascot I 48 48 48 barn. 



Hodges 5 50 41 46 barn, {turn.) 



Turley Mill i 51 51 51 turn. 



Noeton 5 52 45 49 barn, {turn.) 



Holston Station 2 48 46 47 barn. 



Austin Mill i 40 40 40 barn. 



South Fork Holston River. 



Pactolus 3 45 42 43 barn. 



Blufif City 8 42 36 39 bigb. (barn.) 



Emmett 8 39 35 37 bigb. 



Barron i 34 34 34 bigb. 



Middle Fork Holston River. 



Chilhowie 3 37 35 3^ bigb. 



North Fork Holston River (next station below, Austin Mill, has av. 40 

 per cent. =: barn.). 



Loc. No. Max. ]Min. Av. 



Rotherwood 8 43 38 40 barn, (bigb.) 



Mendota 4 4i 36 39 bigb. (barn.) 



Holston P. 5 40 35 37 bigb. (barn.) 



Saltville 7 39 34 37 bigb. 



Big Mocasin Creek (next station below, Rotherwood, has av. 40 per cent.). 

 Loc. No. Max. Min. Av. 



Moccasin Gap 10 40 32 37 bigb. (barn.) 



Willow Springs 2 38 35 36.5 bigb. 



