1 8 HoYLE, Genera of Recent Dibranchiate Cephalopoda. 



4. See IjiMA and Ikeda, Notes on a specimen of Amphi- 

 tretus pelagicus from the Sagami Sea, Annot. Zool. Japan., vol. 4, 

 p. 85 — loi, pi., igo2. 



5. I still consider the validity of this genus extremely 

 doubtful on the grounds given in the " Challenger " Report, 

 p. 78 ; the type has disappeared, and no second specimen has 

 ever been secured. 



6. These two genera may perhaps be identical ; for remarks 

 on the question, see "Albatross" Report, p. 23. 



7. I am not acquainted with any means of distinguishing 

 the females of these two genera, apart from referring them to 

 their proper species. 



8. The question whether Spirula should be referred to the 

 Myopsida or CEgopsida does not seem to me to be finally 

 settled : in the table above it has been placed in the latter : the 

 question has been discussed by Huxley and Pelseneer, 

 "Challenger" Reports, summary, vol. 2, appendix i, 1895; 

 (French translation, Bull. Set. France, vol. 26, 55 p., 6 pis., 

 1895), ^"d LoNNBERG, Notes on Spirula reticulata (Owen) and its 

 Phylogeny, Festskrift for Lilljeborg, 22 p., i pi., 1896. 



9. See JouBiN, Revision des Sepiolidse, Mem. Soc. Zool. 

 France, vol. 15, p. 80 — 145, cuts, 1902. 



10. Sepioteuthis 1 though appearing here in the scheme owing 

 to the form of its fans, really belongs to the family Loliginid®. 



11. The commonest species of these two genera resemble 

 each other so closely that it seems worth while to reproduce 

 here the differential characters given by Pfefifer ("Synopsis," 

 p. 159, 160.) 



Ancistroteuthis lichtensteini : — Hinder end of the fin of the 

 adult produced into a long point, so that the fin is longer than 

 broad ; the carpal fixing apparatus consists of 9 to 1 2 suckers 

 and pads ; the fifth or sixth proximal hook of the dorsal row is 

 not displaced towards the ventral row of large hooks ; the suckers 

 of the arms have no pear-shaped prominence; the pen consists 

 only of the rhachis, and is provided at the end with a small 

 spoon-shaped cone, and a very long solid spine arising from it ; 



