CEPHALOPODS OF THE PHILIPPINE ISLANDS 19 



43. Animals muscular, bottom dwelling; no disparity in size between males and 



females; common littoral octopods .... 44 



Animals pelagic; females with coiled, unchambered shell; males very small; 

 planktonic 49 



44. An inconspicuous water pore between the bases of the arms m the inter- 



brachial region Cistopus indicus (p. 165) 



No water pores between the bases of the arms in the interbrachial region . . 45 



45. A single ocellus in front of each eye; species small to medium size; brownish 



gray with dark reticulations or a conspicuous longitudinal stripe. 



Octopus membranaceus (p. 159) 

 No ocellus 46 



46. First arms longest and largest Octopus macropus (p. 164) 



First arms short 47 



47. Body long and slender, squidlike; arms short and subequal; size small. 



Octopus teuthoides (p. 163) 



Body rounded, saccular; size medium to large; first arms distinctly shorter 



than others 48 



48. Gill lamellae 9 to 11; ligula minute (LLI under 3); head normal. 



Octopus vulgaris (p. 165) 



Gill lamellae 6 to 8; ligula small (LLI under 5); head narrow; color often 



dark with pale spots Octopus horridus (p. 161) 



49. Here are found the four species of Argonauta: A. argo, A. hians, A. hottgeri, 



and A. nodosa. Specimens were not available and they are, therefore, 

 not keyed out here. 



Subclass Nautiloidea 

 Family Nautilidae 



Nautilus pompilius Linnaeus, 1758 



Plate l,a 

 Nautilus pompilius Linnaeus, 1758, p. 709. — Dean, 1901, p. 819. 



Material. — 1 living specimen with shell from Stn. D5409 off 

 Capitancillo Light, between Cebu and Lej^te, in 346 m., green mud, 

 Mar. 18, 1909; USNM 611199. Shells without the animal were taken 

 from the beach and also by trawl at the following localities: Mansalay 

 Bay, Mindoro; Jolo Id.; Diet Lake beach, Sulu Id.; Tilig, Lubang; 

 Stn. 5374 off Tayabas, Luzon; Stn. 5245, Uanivan Id.; Tabaac, 

 Simaluc Id., Tawi Tawi; Observatory Id., Malubutglubat Id., Pala- 

 wan; Mantacao Id. off western Bohol; Stn. 5441 off western Luzon, 

 San Fernando Pt.; Buena Vista, Palawan; Tagbayag Bay, Palawan; 

 Macajalar Bay, Mindanao; Balakias Bay, Lubang. 



As listed above, numerous shells are in the dry collections of the 

 U.S. National Museum, but only one complete animal was taken by 

 the Albatross; its soft parts have hardened in preservation, and ex- 



