14 bulletin: museum of comparative zoology. 



Right. Left. 



Lengtii of first arm 40 36 



Length of second arm 100 90 



Lengtii of third arm 50 24 



Length of fourth arm 25 26 



This form is sufficiently distinguished by the elongation of the second pair 

 of arms. The disparity in length between the two arms of the third pair is 

 noticeable, — the more so since that of the right side has a truncated extremity, 

 as if it had been originally still longer. 



Family POLYPODTDAE, n. n. 



Octopodidae Auctorum. 



POLYPUS. 



Poll/pus Schneider, i84, p. 116. 

 Octopus Lamarck. !99, p. 18. 

 Polypus Hoyle, :01. 



I have elsewhere (: 01) shown that in accordance with the rules of zoologi- 

 cal nomenclature now generally adopted, Schneider's name must take 

 precedence of that proposed by Lamarck. It is no light matter to change a 

 name that has been in daily use for just over a century, but I am so fully con- 

 vinced that the only way of securing anything like uniformity in nomenclature 

 is the rigid adherence to rules, that it seems to me best to make the change 

 and tru.st to its gradual adoption. I notice that this view has been accepted 

 by no less an authority than Mr. Edgar A. Smith, of the British Museum (: 02). 



11. Polypus occidentalis. 



Octopus vulqnris var. americanns d'Orbigny, '53, p. 14, I'late 1, Fig. 1. 

 Octopus occidtntalis lloyle, '86, p. 77. 



HaMtat. — Charles Island, Galapagos L^lands, April 1, 1891 ; one specimen 

 9 , No. 794.3. [H. 39.] 



On my la.st visit to Copenhagen I had the satisfaction of comparing this 

 specimen with Steenstrup's type, in company with my friend the late Dr. H. 

 J. Pofwelt, whose untimely death in July, 1896, cut short a career of unusual 

 promise. 



12. Polypus oculifer, sp. n. 



(rinto 4, FiKH. 3,4.) 



Jlnhital. — CliarlcH Island, (jalai>agos Islands, March 31, 1891; one speci- 

 men 9, No, 7948. [11.40.] 



