ORTMANN: monograph of the naiades of PENNSYLVANIA. 327 



L. H. D. 



Size: (Males) 1. Kelly, Cat. No. 61.2983 68 mm. 44 mm. 36 mm. 



2. Shenango, Cat. No. 61.4097 60 " 41 " 31 " 



3. Aladdin, Cat. No. 61. .3358 52 " 34 " 25 " 



4. do. " " do 40 " 27 " 20 " 



(Females) 5. Kelly, Cat. No. 61.2985 (gravid) 45 " 25 " 28 " 



6. Aladdin, Cat. No. 61.3358 (gravid) 42 " 26 " 31 " 



7. Aladdin, Cat. No. 61.33.58 (gravid) 38 " 22 " 19 " 



8. Godfrey, Cat. No. 61.3360 (gravid) 37 " 22 " 18 " 



The largest individuals recorded here are not surpassed by any specimens 

 from outside of Pennsylvania. 



Soft parts (See Ortmann, 1912, p. 355, fig. 27). Glocliidia (See Ortmann, 

 1911, PI. 89, fig. 24). 



Breeding season: Gravid females were found on Sept. 5, 1913; Sept. 8, 1914; 

 Sept. 15, 1913; Sept. 16, 1913; Sept. 17, 1913; Sept. 18, 1908; Sept. 27, 1907; 

 Sept. 27, 1909; Oct. 5, 1908; Then again on May 20, 1914; May 23, 1911; May 

 24, 1911. 



Glochidia have been observed as early as Sept. 17. On May 20 and 23, dis- 

 charging females have been found. Thus this species is clearly bradytictic. 



Fig. 34. 

 • Truncilla triquelra. 

 m Truncilla rangiana. 

 + Do. (Indian garbage heap). 



Remarks: The female of this species is so peculiar in shape and color, and in 

 possessing the remarkable character of denticulations on the margin of the shell, 



