THE NAUTILUS. 81 



none was found on any other R. I. or Conn, shore as far south 

 as New London. 



All of the specimens were alive when captured, two of them 

 swimming by the undulation of their fleshy pleuropoda or 

 swimming lobes. When not in motion the swimming lobes 

 were folded over the dorsal organs, affording some if not full 

 protection. When handled they exuded from their mantles a 

 red-purple fluid which became bright crimson or wine color when 

 diluted by sea-water or alcohol. 



In life the colors were dark purplish-brown, variously mottled 

 with large areas of dirty white. The distribution and relative 

 quantity of these colors differed much, however, according to 

 the degree of extension or contraction of the animals. It was 

 also noted that the dark pigmented surfaces were thin and easily 

 rubbed off, making color description an uncertain factor except 

 with fresh specimens. In alcohol the dark portions turned 

 nearly black, and the light areas at first changed to a bright pea- 

 green, then back again, in the course of a week, to the original 

 dirty white. 



Two of these specimens, now in the collection of the Boston 

 Society of Natural History, measured 8 inches in length, 7 in- 

 ches across the expanded swimming lobes. These measurements 

 were dorsal and taken before relaxation following death. The 

 other specimens were much smaller. 



The shell, covered by a tough membrane, was oval in general 

 outline, very thin and fragile, and composed of two plate-like 

 layers. A. test with dilute acid proved the inner layer to be a 

 thin surfacing of lime, not quite covering the outer chitinous 

 plate. White, concentric lines, describing smaller arcs towards 

 the hook-like apex, were crossed by finer, radiating lines con- 

 verging at this point. 



The odor of the colored fluid (possibly mixed with other 

 secretions) was slightly unpleasant, and the dyeing quality, un- 

 like the " Tyrian purple " of some mollusks, was not very good. 

 When fresh it was readily washed from the hands, and almost as 

 easily from cloth, but unsized paper appeared to hold the stain 

 rather persistently. No fixing agents, except hot water and dry 

 heat, were tried, however. 



