REPORT ON THE CEPHALOPODA. 93 



edges, and exhibiting a black ring in the centre sharply marked off from the brown 

 ground. Under the lens the dark spots are resolved into aggregations of chromatophores, 

 and it may also be observed that the rings are more deeply placed and shine through the 

 spots, and are therefore probably due to a fixed pigment in the deeper layers of the cutis. 

 The brown spots on the arms bear no rings. 



" The distribution of colour in this species is so characteristic that it can hardly be 

 confused with any other hitherto known. The only known specimen (unfortunately 

 defective) is in the Gottingen collection, and was presented by Dr. Schutte of Sydney." 



The specimen which came into my hands bore the label " Australia," and I have since 

 seen two in the British Museum from Port Jackson and Kangaroo Island, South Australia, 

 and also four specimens in the Liverpool Free Public Museum, and one in the Museum of 

 the Royal College of Surgeons, London, from unknown localities. 



This species furnishes an admirable instance of the uselessness of slight variations in 

 the lengths of the arms as specific characters ; a number of specimens which have been 

 examined with respect to this point giving the following results :^ 



Type specimen, ..... 3 and 2 subequal, 4, 1. 



Specimen in my own collection, . . 4, 1 and 3 equal, 2. 



( A 3, 4, 2, 1 on one side; 4, 2, 1, 3 on the other. 

 Four specimens in the Liverpool Museum,! J g 3, 4, 2, J-^^^^^^^^^j^^ ^^^^ ^^^^^ ^^^^^^^^ 



V D 2, 3, 1, 4 on one side, doubtful on the other. 



" Alert " specimen, .... 2, 3 and 4 subequal, 1. 



The example in the British Museum from Kangaroo Island has a curious thin pointed 

 process about 6 mm. long at the aboral end of the body, which led to its receiving a 

 special MS. name, but in all other respects it agrees so closely with Octopus pictus 

 that I am inclined to regard it as an individual abnormality. 



This specific name appears to have been applied by Blainville to the animal now 

 known as Parasira catenulata, at least d'Orbigny quotes Octopus pictus, Blainville, with 

 a reference to " Faune frangaise, moUusques " as one of its synonyms, with the addition 

 " d'apres Risso," in whose writings I have been unable to find any allusion to the matter. In 

 this case, seeing that there seems to be some doubt as to BlainviUe's application of the name, 

 and as it has, at all events, never obtained currency, it seems right to allow Brock's name, 

 which has the priority in reference to the present species, to stand. , 



Professor Verrill has described a new species of Octopus ^ for which he has selected 

 the name " pictus," being apparently unaware of its appropriation by Brock ; it is quite 

 certain that the two forms are distinct, and therefore as Verrill's name must be changed, 

 I propose that his species should be known as Octopus verrilli. 



' I am indebted to my friend Professor Herdman for measuring these specimens. 

 2 "Blake" Suppl., p. 112, pi. iii. fig. 3. 



