VOYAGE FOR THE DISCOVERY OF SOUTHERN LANDS. 951

brilliant and polilhed as the diamond : in this part is the principal feat of the won-derful phofphorefcence of which I fhall prefently fpeak. Between t’nefe large tuberclesothers fhorter and more obtufe are perceptible, nearly joining each other, and endowedas the larger with a phofphoric property.

Finally, within the interior of the fubflance owing to its tranfparency, are feen amultitude of fmall glands, very narrow, and about a millimeter in length *, whichlikewife participate in a very high degree a phofphorefcent nature.

The colour of thefe remarkable zoophytes when at reft and after death is an opalyellow, mixed with green, difpleafing to the eye : when, however, in their movementsthey contract themfelves, wdiether fpontaneoufly, or on being irritated, the animalinftantaneoufly affumes the appearance of molten iron, and Ihines with much fplendor;but, as that metal in proportion as its heat diminifhes affumes divers {hades of colour,fo this animal as its phofphorefcence difappears, exhibits numerous {hades of colour,extremely pleafing to the eye, light, and varied ; for example, red, the blufli ofmorn, orange, greenifli, and an azure blue : this laft (hade of colour efpecially isequally lively and pure. With this (hade it is reprefented by M. Lefueur,. not only onaccount of its being that of all it affumes the moft graceful, and beft fuited to give ajuft idea of this charming fpecies, but alfo becaufe of its being intermediary betweenthe red of molted iron which it exhibits in its higheft ftate of phofphorefcence, and thegreenifh opal yellow of its ftate of quietude.

With refpecf to the phofphorefcence itfelf, whatever its nature may be, whatevermeans be employed for its production and maintenance, it conftantly, in this fpecies,fhews the characteriftics of a regular and natural function. Indeed, if in a vafe of feawater feveral of thefe animals be placed, they are feen at regular intervals to experiencealternate motions of contraction and expanfion, analogous to thofe occafioned by refpi-ration and drawing breath in more perfect animals. At each contracting motion thephofphorefcence takes place, and afterwards infenfibly diminifbing entirely difappears,till again produced by a new contraction. The appearance of the phofphorefcence mayat pleafure be procraftinated by irritating the animal, either with touching it or fhakingthe water in which it fwims. In every inftance this phofporic property fo completelydepends on the organization and life of the animal that it totally ceafes when life becomesextinft. Nor indeed is this a peculiarity of the pyrofoma, for the fame takes placewith all other marine animals of phofphoric nature.

The locomotive faculty of this animal appears even more enveloped in obfcuritythan its vital functions, and is very limited : it feems, in faCt, to confift excluftvely inthe {lightly contracting and dilating movements I have noticed, the neceffary effeCt ofwhich will be to occafion a trifling impulfe on the water and confequently a retrogadereceflion.

Of what regards the mode of nutrition of this animal I confefs that I have no pofitiveknowledge, and merely give the following as amatterof conjecture. I have mentioned thering of large tubercles difpofed round the infide of the opening in the fore part of thebody, and narrowing nearly to half its fize the diameter of this kind of mouth - y may itnot be poflible that the animal aware from the irritation they will caufe of the entranceof fmall mullufcte with the water into the tubulous cavity noticed, is enabled to contractitfelf to fuch a degree as to clofe the opening of the ring ? The fmall mollufcae thusconfined within the tube, and unable to efcape, in this cafe may there undergo a kind

* The 25th part of an inch.

of