THE CISCO OF GREEN LAKE, WISCONSIN. 



By George Wagner. 



(Leucichthys birgei, n. sp.). 



Type, No. 1709i, Wisconsin Geological and Natural History Survey ; 

 a female specimen, 280 mm. long, taken from 28 meters below surface 

 in Green lake, Green Lake County, Wisconsin, August 3, 1909, by means 

 of gill nets. Co-types, thirty-six other specimens recorded under No. 

 J 709. Collector, H. H. T. Jackson. 



Length 280 mm. ; head in length 3.9 ; depth of body in length 3.6 ; 

 eye 6 in head ; maxillary 2.7 in head ; height of dorsal 1.6 in head ; dis- 

 tance from snout to dorsal 1.8 in total length; depth of caudal 

 peduncle 3.3 in head ; gillrakers 15x2S ; longest gillraker 1.2 in eye ; 

 dorsal rays 9; anal rays 11, scales 8-70-8. 



Body elongate, moderately compressed ; dorsal and ventral outline 

 about equal ; greatest depth in front of dorsal. Dorsal outline of head 

 straight, premaxillaries at a slight angle with it ; maxillaries not quite 

 reaching center of eye ; lower jaw included, the whole head having a 

 sharp, smooth, wedge-shaped outline. Dorsal fin large, its height .67 in 

 its base, the longest ray extending beyond the last* one when folded. 

 Pectoral fins reaching slightly over half way to ventrals. Pectorals 

 and ventrals both large ; adipose fin large, its length .63 in eye ; caudal 

 broad, widely forked. Lateral line straight, somewhat nearer back 

 than belly. Scales firmly attached, fairly uniform in size. 



Color (in formalin), as a whole rather light, darker only above 

 lateral outline; head without black; dorsal and caudal fins with edges 

 somewhat dark ; other fins light. 



The above description is drawn up from the type-specimen. 

 The form, even as represented by the individuals of what was 

 probably a single school, is quite variable ; I therefore add here the 

 principal measurements of all the specimens at present available, 

 the specimens being arranged in the order of their size. 



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