30 VERTEBRATE ANIMALS OF THE UNITED STATES 



C2 Space between dorsal and lateral plates with very many 



series of minute plates 4 . brevirostrum. 



bo In the Great Lakes and upper Mississippi Valley 1 . fulvescens. 



a 2 On the Pacific slope. 



bi Lateral plates about 44 .1. transmontanus. 



62 Lateral plates 26 to 30 .4. acutirostris. 



A. oxyrhynchus^iitchiVi. Common sturgeon. American sturgeon. 

 Extreme length 3,600 mm.; extreme weight 550 lbs.; head 3.5; depth 

 5,75; color olive gray, lighter below; dorsal plates 10 to 14; laterals 

 27 to 29; ventrals 8 to 11 ; rays of dorsal lin 38; anal 27; snout long and 

 sharp, almost as long as the head: Atlantic Ocean and its tributary 

 streams from Main to South Carolina; often common; a valuable food 

 fish. 



Fig. 14. — Acipenser fulvescens {from Jordan b' Evermann). 



A. brevirostrutn LeSueuT. Short-nosed sturgeon. Length 800mm.; 

 head 4; depth 5.5; color dusky; snout very short, about a quarter the 

 length of the head; dorsal plates 8 to 11; laterals 22 to 33; ventrals 6 to 

 9; rays of dorsal fin 41; anal 22: Cape Cod to Florida; not common. 



A. fulvescens Rafinesque. Lake sturgeon (Fig. 14). Length 1,800 

 mm.; head 3.5; depth 5.75; average weight 50 lbs.; extreme weight 

 100 lbs.; color dark olive, often with large irregular blackish spots; 

 sides paler or reddish; dorsal plates 11 to 15; laterals 38; ventrals 10; 

 rays of dorsal fin 35; anal 26; plates large and rough in the young, 

 becoming smoother and often lost with age:. basin of the Great Lakes 

 and the Mississippi Valley and northwards; abundant; the largest fish 

 in these regions. 



A. transmontanus Richardson. White sturgeon. Length 1,500 

 mm.; head 4; depth 7; weight 125 lbs.; record length 4,000 mm.; record 

 weight 1,000 lbs.; color dark gray; dorsal plates 11; laterals 44; ventrals 

 10 to 12; rays of dorsal fin 45; anal 28: Pacific Ocean from Alaska to 

 Monterey, ascending the streams, in which it may remain throughout 

 the year. 



A. acutirostris Ayres. Green sturgeon. Length 2,000 mm.; head 

 4.25; depth 7.5; weight 350 lbs.; color olive green, with a midventral 

 stripe and one on each side above the ventral plates; dorsal plates 10; 



