Kiubjcunilies, Genera, and Suhgenera — Recent and Fossil 151 



iilate (plate 80, figs. 16-18, campamdatum (Say) ; figs. 19-21, multivolvis 

 (Case) ). 



Animal (plate 70, fig. 1, campanulatum) . With short, wide foot, oval in 

 shape, otherwise like Pierosoma. Color dark reddish brown or blackish, 

 bottom of foot very dark reddish with flecks of white, tentacles dark 

 colored with indistinct white rings. There is some variation in the shades 

 of color. The animal is usually very slow in movement. 



ANATOMICAL CHARACTERISTICS 

 PLATE 27 {Hclisotna campanulatum (Say) ) 



GENITALIA. Male Organs (fig. 15). The seminal vesicle (SV) is short 

 and wide (about 2 mm. long and 0.5 mm. wide) and the vesicles are very 

 large and comparatively few in number. They are mostly attached later- 

 ally. A few short \'esicles extend down the ovisperm duct for about 1 mm. 

 The sperm duct (SPD) is about 4 mm. long and 0.3 mm. wide. The 

 prostate (PRS) is long (4.5 mm.) with a short prostate duct at each end 

 which connects with the sperm duct and the vas deferens. There are 

 fourteen rows of diverticula of varying length, the median ones the largest, 

 the outer ones the smallest. Some of the diverticula arc branched toward 

 the end, the section figured (fig. 12) showing four such branches. The 

 section also shows the fan-like pattern of the diverticula. The vas deferens 

 (VD) is a long and narrow duct (16 mm. long). 



The penial complex (fig. 11) is much like that of Helisoma trivolvis. 

 The i^reputium is distinctly pear-shaped, 1.5 mm. long, the vergic sac (VS) 

 smaller, shorter (1.5 mm. long) and club-shaped, and very narrow at its 

 junction with the preputium. The penial gland duct (DC) is very long 

 (5.5 mm.) and narrows considerably at each end where it enters the pre- 

 putium and the vergic sac. Normally, the long penial gland duct is coiled on 

 the preputium between this organ and the vergic sac, as shown in fig. 9, 

 DC. Usually, there is one more or less branched retractor muscle (R^l) 

 but in some specimens two retractors were observed (fig. 9). There are 

 several (1-3) narrow supporting muscles (figs. 5-8, 10, 11) or there may be 

 one wide band with several smaller muscles. In fig. 9, two small muscles 

 are shown below the retractor muscles. These are attached to the wall of 

 the mantle cavity and not to the columella muscle. 



Internally (fig. 10), the preputium has several vertical folds or pilasters 

 and a muscular, cup-shaped penial gland (GL) which is attached by a 

 small neck to the wall of the upper third of the preputium. In section 

 (fig. 1), the gland is cup-shaped, one side of the cup being thicker than 

 the other as shown in the figure (BAV). There are many vertical, thick- 

 walled folds (OF) and a number of small, flat, pavement-like folds in the 

 bottom of the cup from which the gland duct (DC) proceeds to the 

 exterior of the preputium. The space between the preputium and the vergic 

 sac is almost closed by a thick muscular ring or diaphragm (fig. 3, D) 

 which is dependent between the walls of the preputium. The penial gland 

 duct enters the vergic sac immediately above this diaphragm (DY). The 

 verge (fig. 10, V) is club-shaped, tapering rapidly toward the end. 



In figs. 5 to 7, the penial complex of H. campanulatum s))iithi is shown 

 indicating how the preputium becomes pushed upward and the vergic sac 



