LYMN^EID^E OF NORTH AMERICA. 385 



Female organs: Receptaculum seminis large, globular, its duct 

 slender, a trifle longer than the prostate duct ; second accessory albumin- 

 iparous gland large, somewhat pear shaped ; anterior portion of oviduct 

 rather long, slender. 



The protractor muscles (pi. XV, fig. F, 4-8) vary considerable 

 in number and position. The penis retractor was unform in all speci- 

 mens examined. The protractor muscles exhibited the greatest varia- 

 tion. The anterior protractor is made up of one very wide muscle, 

 composed of from two to four branches which again subdivide as 

 they enter the penis-sac. The posterior protractor muscles vary from 

 one to four in number, and likewise vary in their relative positions, 

 in one case (4) being rather widely separated, and in two cases (5, 6) 

 being crowded together. In two examples there was but one anterior 

 protractor. This variation was observed in specimens from Michigan 

 and from two localities in New York. 



Eleven specimens gave the following comparative measurements : 

 Dissection Nos. 23900 to 23905 : 

 Length. Length. Length. Length. Length. Length. Length. 



of 



of 



of 



of 



of 



of 



of 









>enis. 



p.-sac. 



r. sem. 



pro st. 



vas. def. 



pen. ret. 



p.-s. ret. 



Shell. 



Locality 





3.00 



3.00 



5.00 



7.00 



12.00 



1.50 



1.50 



17.00 



Genesee R., 



N.Y. 



2.75 



3.00 



5.00 



4.50 



13.00 



1.50 



1.50 



16.00 



" 



" 



3.50 



3.50 



5.50 



7.00 



13.00 



3.00 



1.50 



17.50 



Erie Canal, 



,N.Y. 



3.50 



3.50 



5.00 



4.50 



12.00 



3.25 



2.10 



17.00 



a tt 



a 



3.25 



3.25 



5.00 



5.50 



13.00 



2.00 



1.50 



18.00 



" " 



" 



2.00 



2.50 



4.50 



5.50 



14.00 



2.00 



1.75 



17.50 



Mackinaw 

 Mich. 



City, 



2.00 



2.50 



4.50 



6.00 



12.00 



2.25 



2.00 



13.50 



Mackinaw 

 Mich. 



City, 



2.00 



2.00 



4.25 



4.50 



10.00 



2.00 



2.00 



19.50 



A dams i. 





3.50 



3.50 



4.50 



5.00 



10.50 



3.50 



3.00 



16.00 



" 





2.00 



2.00 



4.50 



5.75 



12.00 



3.25 



3.25 



18.00 



" 





2.00 



2.50 



4.00 



5.75 



11.00 



3.25 



3.25 



16.00 



" 





It will be noted that the greatest variation occurs in the retractor 

 muscles of the male system, which may be due in a large measure to 

 undue stretching, these muscles being very flexible. In two cases 

 the prostate duct was of unusual length. The difference in length of 

 the penis and penis-sac in several examples is due to the contracted 

 condition of these organs. It will be noted that the ratios are about 

 the same in all cases examined. So far as the genitalia are concerned, 

 catascopium does not differ materially from palustris. 



Range: (Figure 45). Eastern Canada and Nova Scotia west to 

 North Dakota, Great Slave Lake south to Northern Iowa, Northern 

 Ohio and Maryland. 



