148 F. IT. STE\yART. 



tory. CI. Cloaca. CI. ap. Cloacal aperture, cut. Cuticle. D. E. Ductus 

 ejaculatorius. B. L. M. Dorso-laieral muscle-field. D. M. Dorsal muscle- 

 field, ex. ap. Excretory aperture, g. c. Ganglionic collar. G. Ec. Gonen- 

 teric canal, g. s. Germinal syncylium. g-w. Gonocoel wall. /. Intestine. 

 L. L. Lateral line. L. L. g. Lateral line gland. M. D. L. Median dorsal 

 line. M. V. L, Median ventral line. m. ' Mesogloea.' m. c. muscle cell. 

 m. I. muscular layer, m. n. 'Mesogloea' nucleus, n. Nucleus, v.g.w. 

 Nucleus of gonoccel wall. n. r. Circumcesophageal nerve-ring. ces. Q]]so- 

 pliagus. 6!?5. (/. (Esophageal gland-duct. oj'. Oogonium, oy. c. Ovarian caecum. 

 ov. r. Ovarian region, ph. Pharynx. P. S. Protractor spiculorum muscle. 

 p. t. Posterior testis, p. t. r. Posterior testicular region, rh. Kliaciiis. 

 Rec. Rectum. R. S. Retractor muscle, s. Spermatozoon, sc. Subcuticle. 

 sg. Spermatogonium, shg. Shell-gland, sm. I. Submedian line. sp. Spicule. 

 S. V. Seminal vesicle. I'.' Epidermal cell or nerve-cell, type 1. T.- diUo, 

 tyjie 2. ig. ap. Tail-gland aperture, tg. d. Duct of tail-gland. T.R. Testi- 

 cular region, tit. Uterus, vag. Vagina, v. d. Vas deferens, v.g. Ventral 

 gland. V. g. c. Vaginal or vulvar gland-cell. v. g. d. Duct of ventral gland. 

 F. Z. il/. Ventro-lateral muscle-field. V.M. Ventral muscle field. /'//.Vulva. 

 Vu g. up. Ai)erture of vulvar gland. 



PLATE 7. 



Pig. L — Anterior extremity, 0. vulgaris. Adult female, x 80. [a) A 

 large cell of the body space. 



Fig. 2. — Head, 0. vulgaris. X 350. («) Circumoral papilla; {h) circum- 

 oral ring of hair; (c) dorsal row of hair ; (r/) dorsal tooth. 



ElG. 3. — Transverse section, O . vulgaris, male, shortly in front of nerve- 

 ring. X 350. Stain : Safranin, picronigrosin. 



Fig. 4. — Transverse section, O. vulgaris, male, through the nerve-ring. 

 X 350. Stain : Safranin, picronigrosin. 



Fig. 5. — Tail, 0. vulgaris, male. X 350. 



Fig. 6. — Transverse section, male, through cloaca. X 350. Stain : Thionin, 

 eosin. 



Fig. 7. — Gland-cell of lateral line. X 800. Stain : Safranin picro- 

 nigrosin. 



Fig. 8. — Part of a transverse section in posterior oesophageal region. 

 X 800. Stain : Safranin, picronigrosin. 



Fig. 9.— Type 1, epidermal cell. X 800. 



Fig. 10. — Part of a transverse section in posterior ce^ophageal region. 

 X 800. Stain : Safranin, picronigrosin. 



Fig. 11.— Coarsely granular acidophil cell of the body space. X 800. 

 Stain : Safranin, picronigrosin. 



