FRESH-WATER MALACOSTRACA OF ONTARIO 161 



SESSIONAL PAPER No. 39b 



Detroit River, St. Clair River, (Faxon). 

 Strathroy (H. B. Sifton). 

 Niagara (Hagen). 

 Lake Ontario (Girard). 

 Toronto (Faxon), Iroquois (C). 



Fiff. 13. 



^o 



Stomachs of Micropterus dolomieu (C), Lota maculosa, Micropterus dolomieu 

 (Forbes). 



Length up to 65 mm. Usual length of adult individuals, from 40 to 50 mm. 



Rostrum with lateral spines. A single spine on each side of carapace. Areola 

 broad, from J to | of width of body. No teeth on anterior border of third joint 

 of large legs (Fig. 13, a). No middle anterior spine on ventral side of carpus ol 

 large legs. Inner border of hand or propodus quite straight. First abdominaf 

 appendages of male with short straight tips. Annulus ventralis of female without 

 sulcus or processes. 



Cambarus virilis Hagen. Figs. 8,b; 9,b; 10,b; 12,a; 13,b. 



Hagen, p. 63; Faxon, p. 96; Ortmann, p. 113. 



This species appears to be quite abundant in the Georgian Bay but not in 

 Lake Ontario. Like the last species it occurs in open water and also in rather 

 stagnant pools, and in depth down to 8 fathoms. 



Localities. — Lake Superior (Hagen). 



Georgian Bay: Waubaushene, Giant's Tomb, Go Home, McCoy Id., Shaw- 

 anaga. Bustard Ids., Killarney, Tamarac Bay, (Wo); Go Home, (Wa); Wiarton 

 Collingwood, Bustard Ids., Killarney, (R). 



Lake Rosseau. 



Toronto (Hagen) ; Sandy Lake (Ortmann). 



Stomachs of Micropterus dolomieu (C), Perca flavescens, Anguilla chrysypa 

 and Amia calva (Forbes). 



Length up to 90 mm. (as much as 6f in. according to Bundy). Usual length 

 of mature specimens, from 60 to 75 mm. 



Rostrum with lateral spines. A single spine on each side of the carapace. Ar- 

 eola narrow (1/21 to 1/15 of the width of the body). Several teeth along anterior 

 border of third joint of large legs (Fig. 13, b). A middle anterior spine on ventral 

 side of carpus of large legs and occasionally a smaU accessory one between this 

 spine and the inner spine of the carpus (Fig. 10, b). First abdominal appendages 

 •of male with long somewhat curved tips. Annulus ventralis of female ^vith a 

 deep and broad transverse sinus. 



