172 DORCASIA. 



Genus DORCASIA Gray, 1845. 



Dorcasia GRAY, Zeitschr. f. Mai. 1845, p. 87, type H. alexandri ; 

 P. Z. S. 1847, p. 171. BINNEY, Ann. N. Y. Acad. Sci. iii, p. 106, 

 pi. 6, f. M (Dentition). Galaxias (part) BECK, Index Moll., p. 42 

 (preoc.). Of. PFEFFER, Verb. Vereins f. naturwissench. Unterhal- 

 tung zu Hamburg, vi, p. 118, 1887. Also SIMROTH & BOETTGER, 

 Berichte d. Senckenb. Gesellsch. 1885, p. 16, pi. 1, f. 2 (as " Bulim- 

 inus sp."). 



Shell rather large and solid, glossy and unicolored ; umbilicated, 

 globose or depressed with rounded periphery, rather conoid low 

 spire and deflexed last whorl. Aperture oblique or subhorizontal, 

 rounded-truncate, toothless ; the lip thickened, and reflexed at least 

 below. Type D. alexandri. See pi. 38, figs. 6, 7, D. alexandri var. 

 rotundata. Also D. ylobulus, pi. 38, fig. 8. 



Jaw low, wide, slightly arcuate, entirely smooth (pi. 60, fig. 3, 

 D. alexandri). Foot (of alexandri') short and broad, the sole very 

 indistinctly tripartite; upper surface coarsely granular, the gran- 

 ules polygonal, subdivided ; with no trace of pedal grooves ; back 

 with several longitudinal lines, obsolete toward head ; facial grooves 

 well marked and continuous from mantle to head, on both sides ; 

 tail more finely granose, obtuse behind, rounded above, without 

 median groove. Mantle with small right and left body-lobes. 

 Right eye-stalk retracted between branches of genitalia. Blind sack 

 of the foot very long, lying free in body cavity. 



Radula (pi. 60, fig. 6, D. alexandri} having mesocones only devel- 

 oped on middle and inner lateral teeth, the side cusps being repre- 

 sented by lateral extensions of the mesocones. On the outer laterals 

 and marginals the ectocone becomes distinct and well developed. 

 In D. globulus (pi. 51, fig. 3,) both median and lateral teeth are 

 distinctly tricuspid. Marginals a simple modification of the laterals, 

 the broad cutting-point trifid. 



Genital system (frontispiece, fig. 3, D. alexandri) without accessory 

 organs of any kind. Atrium very short. Penis long, larger, and 

 abruptly bent toward the apex where the terminal, short retractor 

 is inserted, its distal attachment being on the lung floor. The vas 

 deferens is not terminal, but enters about one and one-half millim. 

 below apex of penis. Vagina long ; spermathecaon a long branch- 

 less duct, entering high on vagina. 



The specimen of D. alexandri examined by me was kindly com- 

 munciated by Dr. Simroth, and is the same one which supplied the 

 data given in Ber. Senck. Ges. 1894. It is a badly preserved 

 spirit example, and shows signs of immaturity. 



