66 EDWARD DRANE CRABB. 



PLATE I. 



FIG. I. Reproductive system of Lymncca stagnalis apprcssa Say, viewed 

 from the ventral side, with parts distended and partly diagrammatized. 



AN, anus; AG, albumen gland (albuminiparous gland, F. C. Baker, '11) ; 

 AGD, albumen gland duct; C to O, regions in the hermaphrodite gland and 

 duct in which ovarian or free, ripe ova were found ; CD, common duct of the 

 albumen gland and of the oviduct ; COI, copulatory organ invaginated ; 

 (larger sac of penis, H. B. Baker, '25) ; CU, convoluted part of uterus 

 (uterine portion of oviduct, F. C. B., '11) ; FO, female orifice; HD, her- 

 maphrodite duct (ovisperm duct, H. B. B., '25) ; HG, hermaphrodite gland 

 or ovotestis ; IO, intromittent part of copulatory organ (verge, H. B. B., '25), 

 [not fully retracted, Fig. i, extended, Fig. 2] ; LI, liver ; MMG mass mem- 

 brane gland (first accessory albuminiparous gland, F. C. B., 'n) ; MO, 

 male orifice; OV ', oviduct proper; PG, prostate; PO, pulmonary orifice; 

 SPO, sperm receptacle duct-orifice; SPR, sperm receptacle (spermatheca, 

 F. C. B., 'ii ; bursa, H. B.-B., '25) ; SPRD, sperm receptacle duct; VD, 

 vas def erens ; VG, vagina (free portion of oviduct; vagina is SPO to FO, 

 my Fig. F. C. B., 'u). MO, FO, PO and AN are represented in their 

 proper spatial relationship as regards each other and the entire reproductive 

 system. 



FIG. 2. Excised tip of evaginated copulatory organ, reconstructed from 

 living and sectioned material, freehand drawing, labeling as above. 



