238 



THE CHICAGO ACADEMY OF SCIENCES. 



tinctly tricuspid, the cusps being subequal (fig. B). In specimens from 

 New Jersey the marginals began at the ninth tooth, the seventh and 

 eighth teeth being transitional. 



GENITALIA (plate XI, fig. B) : Male organs: Penis-sac wide, 

 rather long; penis very narrow, from four-fifths to seven-eighths the 

 length of the penis-sac; penis retractor and penis-sac retractor of 

 about equal length (as long as penis), separate, entering the columellar 

 muscle in close proximity; protractor- muscles four in number, two 

 very narrow muscles posterior and two wide, powerful muscles an- 

 terior; vas deferens a little longer than penis and penis-sac; prostate 



Distribution of *" 

 UMBILICATA \ 



FIG. 21. 



duct as long as penis; prostate long, ovate, flattened with rounded 

 extremities, entering the prostate duct by a narrow construction; pos- 

 terior portion of prostate very narrow. 



Female organs : First accessory albuminiparous gland very large, 

 pyriform; lower portion of oviduct short and thick; receptaculum 

 seminis ovate, its duct very narrow and about half as long as the vas 

 deferens. The other organs as usual. The receptaculum seminis is 

 salmon colored, but the other organs are flesh-colored or whitish. 



The genital organs, with the exception of the penis muscles, are 

 very uniform in this species. In two specimens examined the penis 

 retractor was attached to the penis-sac retractor about midway of the 

 latter, and in one specimen one of the posterior protractor muscles of 

 the penis-sac was attached to the latter at the same point as the penis- 



