300 HKT I PO 1'LATKS. 



when- it is imbedded in /% the muscular stein of the gill laid 

 open. p. The larger branchia of the right side, showing the 

 venous surface, p' . The same of the left side, showing the 

 venous surface, q. The smaller branchiae of the right side, 

 showing the arterial surface, with r, the tleshy skin entire, the 

 dotted line indicating the passage of the branchial artery into 

 it. </'. The smaller branchia of the left side. 8. The common 

 stem of the branclme, by which they adhere to the inner sur- 

 face of the mantle. 10. The branchial veins. 11. The valves 

 placed at their terminations in the ventricle, t. The ventricle 

 or systemic heart, laid open. 12. The origin of the U 

 aorta. i:5. The artery of the glandular ovarian apparatus. 

 14. The siphonic artery. 15. The artery of the intestine. 

 16. The larger aorta. 16'. Its muscular origin or the continu- 

 ation of the ventricle. 17. The valve at the extremity of this 

 part. 

 2. A lamina of the larger brauchia magnified, showing its subdivi- 



visions into the smaller laminae ; !"> 



The letter and figures as in fig. 1. Owen, 1. c. 



Plate 14. 



1. Female organs of Sepia officinalis. Milne-Edwards, in Cuvier's 



1 ii'gne. Anini. Moll., t. 1, e 38 



a. Anus. f. Intestine, o v. Ovary, o d'. Oviducal aperture. 

 o d. Oviducal gland, g n. Nidimental gland, g n. Accessory 

 glands. 



2. Female organs of Eledone moschata. Keferstein, 1 c., t 121, f. '. 



o d'. Oviducal apertures, x. Oviducal glands, o v. Ovary. 



3. Male organs of Loligo vulgaris. Duvernoy, Mem. Acad. Paris, 



xxiii, t. 7 38 



1. Testicle, t'. Testicle case, v d. Vas deferens. v d'. Its 

 opening. V s. Vesioula seminalis. p /. Prostrate -land. 

 bip. Spermatophore reservoir, p. Penis. 



4. Male organs of Octopus vulgaris. Cuvier, Mem. sur les Moll. 



( Y-ph., t. 4 38 



References as in lig. 3. //. Muscle. 

 ". Male organs of Sepia officinalis. Duvernoy, 1. c 38 



t. Testis. v d. Vas deferens. D * Vesicula seminalis. 

 p r. Prostrate, b s p. Spermatophore reservoir, p. Penis and 

 genital aperture. 



Plate 15. 



I fectocotylized Arms. 

 From Yeranv, < Yphalopodes de la Mediterranee, t. 41 :!'. 



1. Tremoctopus ( 'arena'. The arm developed. 



2. Ibid. The arm not developed from its sack. 



3. Ibid. The terminal vesicle opened and the sinuous white thread 



exposed. 



1. .">. Side and front view of the Hectocotyle of the Octopus. 

 I. Hectocotyle of the Argonaut. Tricocephalus acetabnlaris of 



Thiaje, as figured by that author. a. Orifice of the mouth. 



h. Alimentary canal. c. Ovary. d. Spotted membrane. 



ef. Double series of suckers. 

 1 Hectocotyle of the A rgmiant, as figured by Costa. Actual size. 





