CEPHALOPODS OF THE PHILIPPINE ISLANDS 161 



Measurements and indices of a female Octopus membranaceus 

 Quoy and Gaimard are: 



Type. — Museum National d'Histoire Naturelle, Paris. 



Type locality. — New Guinea. 



Discussion. — It is with some doubt that I place this specimen in 

 the above species. A survey of the species in Robson (1929) reveals 

 nothing which fits the present female. Sasaki (1929) is also of little 

 help except for the description of 0. ovulum which approaches this 

 species rather closely in some respects. The specimen illustrated 

 (Sasaki, 1929, pi. 11) is somewhat similar except in the structure 

 of the ocellus. Experience with ocelli, however, makes me disregard 

 this difference because they are very variable and often change ac- 

 cording to the preservative and especially with the length of preser- 

 vation. Perusal of Pickford's magnificent study of the Indo-Malayan 

 octopods (see p. 2) leads me to the conclusion that, despite certain 

 differences, the specimen belongs to 0. membranaceus, of which 0. 

 ovulum is tentatively considered by Pickford to be a synonym. 



Distribution. — New Guinea; Japan (Sasaki); Amboina; Red Sea 

 (Adam); east Africa; central Pacific; Philippines! 



Octopus horridus d'Orbigny, 1826 



Plate 3, a 

 Octopus horridus d'Orbigny, 182G, p. 144. — Robson, 1929, p. 21. 



Material. — 1 9, ML 50.0 mm., 2 cf cT, ML 22.0 mm., from reef at 

 Port Tilig, Lubang Id., July 15, 1908. 1 cT, ML 35.0 mm., from tide 

 pool at Canimo Id; near Daet Point, eastern Luzon, June 15, 1909. 



Description. — The four specimens listed above were placed in 

 this species with some hesitation. As noted in "Discussion" below, 

 they present some features dift'ering from those of previous specimens. 



The mantle is globular, very blunt posteriorly, and widest in the 

 posterior third (MWI 60-82). The head is narrow (HWI 50-68) 

 and is set off from the body by a narrow constriction. The eyes are 

 prominent. 



The funnel is narrow and tubular, free for most of its length, and 

 bears a broad W-shaped organ. 



