LYMN^EID^E OF NORTH AMERICA. 423 



Genitalia: (PI. XII, fig. H). Male Organs: Penis-sac long and 

 cylindrical, 3.50 to 5.00 mill, in length; penis short and thick, 2.00 to 

 3.00 mill, in length, or about one-half the length of the penis-sac ; vas 

 deferens 24.00 to 26.00 mill, in length, or about five times the length 

 of the penis-sac ; prostate portion of vas deferens 6 mill, long ; prostate 

 very large and somewhat quadrate, narrowing posteriorly to form a 

 rounded tube as large in diameter as the oviduct; a side view of the 

 prostate shows it to be very elongate-ovate; protractor muscles six 

 to seven in number, four narrow, slender posterior muscles with 

 numerous small branches entering the penis-sac and two to three large 

 anterior muscles, with many branches entering the penis-sac. Penis 

 retractor 3.00 mill, long, narrow; penis-sac retractor wide, ribbon-like, 

 swollen in the middle and entering the penis-sac by many small 

 branches. The retractors have a common insertion in the columellar 

 muscle. 



Female Organs: Similar to those of emarginata; the first acces- 

 sory albuminiparous gland is somewhat pear shaped, elongated and 

 very large; the second accessory albuminiparous gland is very small 

 and rounded and placed rather high up on the oviduct; receptaculum 

 seminis large, rounded, its duct 5.00 to 6.00 mill, in length and at- 

 tached to the oviduct one mill, from the vaginal opening, by a bulbous 

 termination. 



The organs are colored as follows : Penis and penis-sac yellowish, 

 prostate yellowish or amber-colored; ovotestis yellowish, albuminipar- 

 ous gland greenish, receptaculum seminis pearly white, and the other 

 organs yellowish. 



The genitalia measure as follows: (Dissection No. 23667). 

 Ret. Vas. 





Penis- 



mus. 



Ret. mus. Vas. 



def. 



Rec. 







Penis. 



sac. 



penis. 



penis-sac. def. 



prot. 



sem. 



Shell. 





3.00 



5.00 



3.25 



2.25 24.00 



6.00 



4.20 



19.00 



Michigan. 



2.75 



3.50 



3.00 



2.00 24.00 



6.00 



6.00 



20.00 



" 



3.00 



4.25 



3.00 



2.25 25.00 



6.00 



5.00 



23.50 



(( 



There is some variation in the lengths of the penis and penis-sac 

 but otherwise the measurements are quite uniform. The form and 

 position of the protactor and retractor muscles of the male organs are 

 also very uniform. 



The genitalia of angulata differ from those of emarginata prin- 

 cipally in the form of the first accessory albuminiparous gland which is 

 longer and more spindle shaped. 



Range: (Figure 47). Michigan to Minnesota, Northern Michi- 

 gan south to Southern Wisconsin. A race of the Transition (Caro- 



