214 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [4] 



cannot be saved. The measurements of the soft external parts of 

 Ceplialopods are, for the most pajt, only approximate, and they are not 

 all of equal value, for some parts are more changeable in size and shape 

 than others. The long, contractile tentacular arms, especially, are lia- 

 ble to grout variation in length according to their state of contraction 

 or extension, and therefore their relative length is of little or no value 

 in discriminating species. Unfortunately, this, either by itself or com- 

 bined with the length of the 'body' as total length, is often the princi- 

 pal one given. The circumference of the body varies, likewise, accord- 

 ing to its state of contraction or relaxation, and the 'breadth' of the 

 body, when such soft creatures are stranded on the shore, will depend 

 much upon the extent to which it is collapsed and flattened from its 

 proper cylindrical form, and is of less value than the circumference. 

 Measurements of the length of the bod}', to the mantle-edge, and to the 

 bases of the arms; length and circumference of the various pairs of 

 short arms; of the length and circumference of the head; size of the 

 eyes ; length and breadth of the tail-fin ; size of the largest suckers on 

 • the different arms; and size of the 'club' of the long arms, are all very 

 useful and valuable. The shape of the tail-fin should be carefully noted, 

 also the presence or absence of eyelids, and of a sinus or groove at the 

 front edge of eyelids. The size and shape of the thin internal 'bone' 

 or 'pen' is particularly desirable. All parts of Cephalopoda contract 

 to a very great extent, when preserved in strong alcohol for some time. 

 Even the horny jaws and sucker-rings may decrease as much as 20 per 

 cent, in size, and the soft parts much more. Usually it will not be pos- 

 sible to preserve the pen in any satisfactory shape by drying, for it 

 cracks in pieces and curls up. It may be preserved packed in salt, in 

 brine, or in alcohol. The same is true of the beak. The horny rims of 

 the suckers can usually be dried, but are better by far in alcohol or 

 brine. The parts most useful for preservation in alcohol or salt, in cases 

 when only a portion can be saved, are the long tentacular arms, espe- 

 cially their terminal 'clubs,' with the suckers in place; the short arms, 

 with their suckers; of these the left arm of the lower, or ventral, pair 

 will probably be the most valuable, being usually the one that will 

 show the sexual distinction, by the alteration of its suckers, toward the 

 tip or in some other part; the lateral arms next to the ventral are next 

 in importance; the caudal fin, and if possible the entire head, should be 

 preserved; also the 'pen,' if possible. In cases where the head cannot 

 be saved entire, even with the arms removed, the beak and tongue, and 

 other fleshy parts in and behind the beak, should be carefully preserved, 

 as nearly entire as possible, either in strong brine or in alcohol of not 

 less than SO per cent., which is generally the best strength for all kinds 

 of Ceplialopods. 



