/a1 



The Nautilus. 



Vol. v. PEBKUARY, 1892. No. 10. 



MOLLXJSKS OF DORCHEAT BAYOTJ AND LAKE BISTENEAU, 

 LOUISIANA. 



BY T. AVAYLAND YAUGHAN. 



Dorcheat Bayou might, with some degree of propriety, be called 

 a river. It is the largest stream crossed by the V. S. and P. Rail- 

 Road between Shreveport and Monroe. 



It rises in Nevada County, Arkansas, flows across Columbia 

 County, in that state, into Webster Parish, Louisiana. Toward the 

 southern portion of Webster Parish, it widens out, and forms Lake 

 Bisteneau, which extends out of Webster Parish, forming the bound- 

 ary between Bienville and Bossier Parishes, and empties into Red 

 River, between Bossier and Red River Parishes. 



I do not know precisely the length of Dorcheat. Its width and 

 depth are both variable, depending upon the flooding rains. When 

 I collected there in June, during low water, in some places one could 

 wade across without getting in water much over knee deep. The 

 stream was from twenty to fifty feet wide, I should judge. My 

 collecting was done near the railroad crossing. Here Dorcheat had 

 well defined banks, often composed of white sand or pebbles. These 

 pebbles are very note-worthy. In some places, they form the bed 

 of the bayou, and are fine places to collect from. % 



Lake Bisteneau is almost thirty miles long. Its width varies 

 from thirty to sixty feet in summer to one mile in winter. There 

 are no well defined banks to Bisteneau, the land sloping down 

 gradually to the water's edge. The bottom of this body of water is 

 abominable; one often mires almost to his waist in the nastv mud. 



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