IX 



TEXT FIGURE 8. Section of tlio fin. 



1, 4, 6. upper, middle and lower fasciae of the fin. 



2. muscle bundles parallel to the surface and perpendicular to the base of the fin. 



3. blood vessel. 



6. muscle fibres parallel to the base and surface of the fin. 



7. muscular septa perpendicular to the surface of the fin. 



TEXT FIGURE 9. Ring of an unsymmetrical sucker. 



A. from above. 1- outline of ring of accessory teeth. 



B. in section. 2. outline of sucker. 



TEXT FIGURE 10. The upper surface of the siphon. 



1. siphonal (articular) cartilage. 4. the posterior siphonal protractor. 



2. lateral siphonal valve in section. 5. siphonal retractor. 



3. the anterior siphonal protractor. 6. oblique surface of origin of the siphonal retractor. 



7. lower wall of siphon. 



TEXT FIGURE 11. The jaws. 



A. the upper jaw. M. ala of upper jaw. 



B. the lower jaw. ^'-^ „ „ lower „ 



G. the jaws articulated. Ax. axis around which the jaws move. 



BM. retractor mandibuli. 



1. Course of the muscle fibres which draw down the lower jaw. 



2. „ ,, „ upper muscle fibres of adductor of jaws. 



3. „ „ „ middle „ „ „ „ ,, „ 



4. „ „ „ lower „ „ „ „ „ „ 



TEXT FIGURE 12. Three rows of radular teeth. 

 TEXT FIGURE IB. Section through the epithelium of the rectum. 



A. of a squid 2 cm. long. B. of an adult. 



F.V. food vacuole? 



TEXT FIGURE 14. Model of the lumen of the forward end of the third gland 



of the seminal vesicle X. 



A. from the outer side. B. from behind (in section). 



TEXT FIGURE 16. The oesophageal, buccal, and brachial nerve rings, seen from the side. 



1—5. first, second etc. brachial ganglia. 



6. infrabuccal connective. 



7. propedo-buccal connective. 



8. cerebro-buccal „ 



9. cerebro-propedal „ 



10. bucco-spanchnic „ 



11. small nerve to the nuchal and cephalic retractors. 



12. viscero-stellate connective with the pallial nerve. 



13. visceral nerve with the viscero-branchial connective. 



