88 Messrs. Hancock and Embleton on the Anatomy o/Eolis. 



Fig. 2. Papilla with gland of E. Farrani, 



Fig. 3. Ditto ditto of E. olivacea. 



Fig. 4. Ditto ditto of E. papillosa. 



Fig. 5. Longitudinal section of papilla of E. papillosa, showing interior of 

 gland, &c. : a, great central channel ; b, diverticula therefrom. 



Fig. 6. Globules from ovate vesicle, highly magnified. 



Fig. 7. Transverse section of gland of papilla of E. papillosa : a, great cen- 

 tral vessel ; b, diverticula from it. 



Fig. 8. Transverse section of ovate vesicle. 



Fig. 9. Highly magnified representation of a papilla of^. papillosa: a, the 

 gland ; b, fine vessel leading from gland to ovate vesicle c ; d, ori- 

 fice at apex of papilla ; e, muscles attaching vesicle to wall of pa- 

 pilla ; //, external wall of space in which the blood circulates in 

 contact with the external surface of. the gland; g g, muscular bands 

 inclosing cellular spaces between // and the skin of the papilla ; 

 h, skin of papilla; i, vibratile cilia on external surface of ditto; 

 kk k, circular and longitudinal muscular fibres of skin. 



Plate V. 



Fig. 1. Longitudinal section of ovate vesicle. 



Figs. 2 and 3. Spermatozoid bodies from ovate vesicle of E, coronata. 



Fig. 4. Spermatozoid bodies from ovate vesicle of E. olivacea. 



Fig. 5. Elliptical bodies inclosed in bags or utriculi with the spermatozoid 

 bodies of E. coronata. 



Fig. 6. Utriculus or bag from ovate vesicle of E. coronata, containing the 

 two kinds of bodies mentioned under fig, ^5. 



Fig. 7. Vesicles or globules containing granules from the gland of papilla 

 of E. papillosa. 



Fig. 8. The granules more highly magnified. 



Fig. 9. Utriculi from ovate vesicle of E. papillosa, containing the sperma- 

 tozoid bodies. 



Figs. 10 and 11. Spermatozoid bodies from same : aa aa, b b, cc, different 

 appearances presented by the filaments or tails of the spermatozoid 

 bodies of E. papillosa. 



Fig. 12. Part of a transverse section of the wall of ovate vesicle of E. papil- 

 losa, showing the interlacing muscular fibres. 



Fig. 13. Spermatozoa from generative oi'gans of E. papillosa. 



Fig. 14. Anterior view of Eolis papillosa from spirits: c, cutting-jaws; 

 b, inner lip ; d, folds of lining membrane, &c. of channel of mouth ; 

 e, outer lips ;/, fold of integument external to outer lips ; g, labial 

 tentacles ; h, dorsal tentacles ; i, anterior margin of foot. 



Fig. 15. Inferior view of head of Eolis olivacea in its natural state. The 

 letters in this fig. as far as they go are as in fig. 14. 



Fig. 16. General view of viscera, &c. of Eolis papillosa from above, the 

 dorsal skin alone having been removed : a, buccal mass ; b, cere- 

 bral ganglia with the nerves passing off from them ; c, ganglia at 

 the base of dorsal tentacles, supposed to be olfactory ; d, oesophagus ; 

 e, stomachal bulb ; /, great central canal; g g g, primary and se- 

 condary branches from ditto ; h, true intestine ; i, anus ; k, por- 

 tions of male generative organs ; I, ovarium ; m, ventricle of heart, 

 with aorta passing forwards from it ; n, auricle of heart. 



